> the organization managing the national French power grid (Enedis) has been in the process of replacing the legacy “dumb” electricity meters by “smart” meters, known under the brand name “Linky”
My jurisdiction, Ontario Canada, mass implemented these and found that people didn’t really shift their peak demand use much and it’s debatable if the amount spent was worth it. Costs just as much to implement for light users but they’re diminishing returns for any habit changes.
Also went all-in on submetering small units like condominiums+apartments where there’s not much tenant/occupant ability to control their usage/equipment. If anything, just further encourages owners/builders to install the poorest efficiency stuff since they’re not paying the usage bill.
Not surprising that other tactics are more effective (dirt cheap LEDs, renovation programs, improving appliance efficiency… my TV and computers use a fraction of what they used to, wall warts are all SMPS now).
Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
I really wish they could push the telecoms to focus on CPE efficiency since I’m forced to use their equipment.
The real long term idea with smart metering isn't so much demand savings (though I think it was billed as that; and I agree the results are very underwhelming from everything I've seen), it's to start allowing dynamic energy tariffs and getting people incentivized to move load to cheaper times.
We have some of them in the UK and you can see the price differences quite clearly: https://agileprices.co.uk/
I think the idea of having one (or maybe a crude day/night) tariff is really antiquated now when wholesale prices swing so much because of renewables. We are getting to a place where electricity is going to be free/negative a lot of the time and very much more expensive for other time slots.
However, I don't know how much consumers can do about this apart from buying batteries (which is a good thing). I don't think many people will start eating their dinner 3 hours earlier or later or do washing in the middle of the night to save a few dollars here and there. I suppose AC/heating would use enough that it would be worth turning it down at certain times of day.
Really where all the money to be made here is being able to get cheap industrial processes that consumer a load of electricity that can be switched on and off, so only working 25% of the time. This is hard though because there is a lot of capex (and opex) to having equipment and people sitting around doing nothing when the price is too high. But I think the energy savings will be so great there will be something that comes along for this - potentially hydrogen electrolysis.
I got solar last year, so ots been interesting to see how habits change (or dont).
The first stuff was obvious. Our hot water and pool pump were already on timers so those were switched from night to day. Now on sunny days that's a free.
We've moved the dishwasher from night to day. The washing machine was already on day, so no change there.
We gave a small (5kva) battery so a chunk of our evening usage is covered.
There are a few other more subtle habits, harder to spot, and perhaps with more limited gains. Some random oven usage (for not-meal things) is more likely to happen during a sunny day,that sort of thing.
So yes habits have changed, and obviously our grid usage is massively reduced (by about 70%). But equally were not anal about it - things still run when they need to run.
Disclaimer: this is anecdote, not data and ymmv. But saving money is a powerful motivator.
Curious: aside from running a cleaning cycle or seasoning a cast iron pan (both of which are at least meal-adjacent), what other non-meal things happen in an oven?
"apart from buying batteries" - that is imo precisely enough. We are nearing a time, where a battery that would flatten the avg household demand curve costs under $2000 (without installation costs), and that might be quite enough to change how electrical production works.
Yes, poorly worded from me. I meant more households can't really do a huge amount about load shifting without batteries. Not that batteries are a bad idea or not workable.
Snark notwithstanding, a thousand batteries distributed close to actual consumers give much more resilience against grid outages, like transmission lines or transformers damaged by a hurricane.
So rich people? So they can save money while people who can't afford a battery cannot. I guess it's like this for most cost-saving investments, but doing it this way hardly contributes to a more fair society.
>> The real long term idea with smart metering isn't so much demand savings (though I think it was billed as that; and I agree the results are very underwhelming from everything I've seen), it's to start allowing dynamic energy tariffs and getting people incentivized to move load to cheaper times.
The original long/medium/short-term goal of "smart" meters was to eliminate the need to manually check meters and integrate that into the billing systems. It was a direct cost savings to delivery companies. All the fancy variable pricing stuff is an afterthought.
I phrase it as utilities got a gov-mandate to install you new stuff, pass on the cost to you, and save some monthly/bi-monthly opex cost that they can pocket themselves (or at least pat themselves on the back for).
If it costs more than it saves, they don’t mind, actually that’s great (for them).
In rural areas in Ontario, the system used 3G (and for some reason I think only supported 2G in the past) to send readings. So that will be another truck roll (or more likely, cheque to telecoms to keep up some old infra).
I also suspicious of $$$ technical investments to reduce relatively small costs (especially ones where a lot of the dollars leave the area).
It also facilitates half hourly settlement. Previously we used standard profile curves based on the average household to attribute consumption to each 30 minute settlement period, where with smart meters sending half hourly reads you can settle based on the actual consumption.
The transition period includes "elective half hourly settlement" which basically means that as a supplier you can selectively settle meters on a half hourly basis, which created an interesting (but time limited) arbitrage opportunity where you could do some data science to predict which meters would be beneficial to settle half hourly or not
I’m a bit confused: why do they need visibility into individual household’s load to accomplish this? Can’t you just look at what the whole city is drawing and order based on that?
Or do you mean fully dynamic pricing/billing to end users?
I think this is for situations where customers can choose a 3rd party energy provider. The utility transmits energy to the user and settles with the energy provider.
Makes sense to settle that up near real time, I guess.
This is on the wholesale side - as a supplier your customers consume energy which you're responsible for purchasing, and it's priced in 30 minute chunks. To get visibility into when your specific customers are consuming energy you need smart meter data from the household level
Eating dinner no, but if your washing machine and dishwasher have an internal timer function (most relatively recent models of both appear to), it's pretty easy to load the appliance and tell it to turn on later that night.
With dynamic tarrifs around here you sometimes make money by doing it during the day, especially on sunny windy days as you get money back for using electricity at that time. My bill is about two thirds of what it would be otherwise (since I cannot install solar panels or batteries it's the only way to have any advantage).
I've automated it so it picks up if the prices goes below a certain set amount, though that's not for everyone.
Btw my parents have been doing off hour washing since the nineties (we've had double meters for a long time). It's nothing new.
The point is that 99% of the contracts have no "dynamic prices", they have few different tariffs established up front an year for the next. In this case you do not need a smart meter to shift load. You simply look at the "current year tariffs" and that's is. If we have dynamic prices than we need a standard data bus for every home appliance connectable to a personal automation or directly to the meter, without that manual load shifting is extremely limited.
In France there is a VERY LIMITED system allow a two wire connection for big appliances were the meter simply tell "cheap or expensive" state and the appliance now that "now the electricity is cheaper, now more expensive". It's way too limited. New homes have since some years a mandatory mitering but without dynamic prices and made to be piloted and throttled loads it's just expensive eye candy stuff.
Personally I have automated via HA as much as I can but such automation is essentially just switches HA can open or close via Shelly integration, there is no real smartness in all appliances even if it's damn cheap adding it from the initial design phase.
My personal experience with "smart" thermostats is that my electric bill went up.
By "smart" I just mean programmable. I had settings for morning, daytime (nobody home), evening, and night. It makes no sense but my total costs went up. This was years ago, so I don't remember exactly what temps I had set for the different times of day. Now I just set the A/C at 76 and leave it there.
Let me paint you a scenario where this is possible: you leave home at 9 AM, and the A/C stops. The house slowly gets hot, maybe 95°F. You plan to arrive at 9 PM, so you program the A/C to get the house to 76°F, which the thing thinks it can do in 1 hour at full blast. But the energy price between 8 PM and 9 PM is the highest of all day: you just programmed the A/C to the worst.
Instead, now you leave it keeping 76°F, and the thing can do it working at 10%. You consume more energy at the end of the day, but the consumption is spreaded through the cheapest hours in the middle of the day, and only a small fraction of it is consumed in the expensive hours from 6 to 10 PM. This is how freezers work, cooling intermitently as the thermostate goes off limits.
I would test if it is worthy money wise, not energy wise, to put the A/C at full blast in the cheapest hours. Say from 4 to 6 PM (the cheapest here in Spain), to get the house as cold as possible, and then try to play with A/C at maybe 5% letting it rise until reaching 76°F at 9 PM.
> I would test if it is worthy money wise, not energy wise, to put the A/C at full blast in the cheapest hours. Say from 4 to 6 PM (the cheapest here in Spain), to get the house as cold as possible, and then try to play with A/C at maybe 5% letting it rise until reaching 76°F at 9 PM.
Depending on how big the house is and how well insulated it is, it very well may make for a big thermal battery and this would work well.
If small and/or poorly insulated or drafty then this will not work well.
It might be, you should research how your region produces energy.
For example, where I live the energy produced from 10:00 to 18:00 is almost 100% solar, eolic and nuclear (https://www.esios.ree.es/es/balance?date=04-07-2024&program=... , orange and red bars are solar, light green are wind, dark blue are nuclear). Energy after 19:00 starts to draw gas (yellow bars) to cover the fall in solar production, peaking at 21:00. Incidentally, this also matches prices going from ~5 cents/kWh to ~20 cents/kWh (https://t.me/tarifaluz/3665). So for me it's both ecofriendy and moneyfriendly to shift as much consumption as possible to the 13:00-18:00 hours.
Eco-friendly, possibly, buy cheaper? Maybe not. It depends on when you arrive home. If you arrive home during peak hours when your utility prices are higher, it can be cheaper to run the a/c earlier, while you're not home, to at least get the temperature down into the rough ballpark of where you want it, and then maintain that temperature into the peak hours.
Even the eco-friendly bit isn't always clear, depending on your equipment. It might use less energy overall to maintain your desired temperature 24/7, even when you aren't there. Your particular equipment may run less efficiently if it has to go on full blast for an extended period of time to do a large temperature change when you first get home.
It uses the least energy, but here we are talking about demand shifting to make use of variable electricity sources. It can be worth using more cheap solar energy in the middle of the day instead of less natural gas later on.
Not always because it depends on many factors such as demand energy pricing. The house also has heat inertia, meaning it could take hours to reach a ceratin temperature, so you'd have to turn on the AC hours in advance before you arrive home.
Cool thing is I don’t care about the temperature of the solid mass inside of where I am, just the air really.
I know when I turn on the A/C in my office, it’s not going to cool the concrete wall/floors/ceiling much in the 8h I’m there before I shut it off for the day. And that’s fine.
The solid mass inside the building, the walls and floors heat the air and the AC is working harder to keep up. Also exposed glass to direct sunshine that creates a greenhouse effect.
The key point is that an insulated house acts as a heat/cold storage device, so it's like buying booze and pouring it into a (slightly leaky) bucket during happy hour, to drink later. Even if you loose a bit to the leaks, you're still saving money overall by buying the booze when it's cheap.
With heat pumps (like AC) and condensing boilers, it is often more efficient to run for longer and slower as long as that makes your appliance run more efficiently (lower flow temperatures for heating, higher for cooling). Requires the system to support modulation though.
I haven't been able to find even specific case examples showing which consumes less energy: turning down heating/ac when no one's home or just keeping it on constantly.
I'm sure it's pretty complicated because buildings vary, but someone who understands heat transfer should be able to do it at least for a few ideal spherical cows...
It does make sense if you were scewing around with the temperature values in excess of 2°C, because the HVAC would work harder to reestablish a new steady state. Most houses have thermal mass and heat inertia and sometimes it takes hours to reach a new temperature set point, the HVAC working at full load to do so. It depends on many factors and it's not easy to optimize without logging the temperatures, the operating cycles of the HVAC and understanding the whole process.
Due to inflation, the expected state is your costs will go up, even in the case of a small improvement in energy use. A number of western countries also seem to be in a state of energy crisis that could explain the price going up beyond inflation.
So that is less informative than it could be. Did you see your real energy use rise?
> it's to start allowing dynamic energy tariffs and getting people incentivized to move load to cheaper times.
That’s what they rolled out with them, but insufficient change to habits.
> I suppose AC/heating would use enough that it would be worth turning it down at certain times of day.
This is generally the big win, and why they’ve had to still create a program to subsidize smart thermostats and payments to enable the back off features.
Mass installing smart meters to incentivize the public at large to buy+install smarter thermostats is a less effective and more expensive strategy than giving the thermostats away and writing users a guaranteed cheque in exchange for remotely controlling it.
(There are other dynamics at play: electricity here is generally cheap and I pay more in fixed charges than consumption and the heating side is almost universally fossil fuel/wood but that’s achangin)
> That’s what they rolled out with them, but insufficient change to habits.
If that's the case, then that means they didn't set the incentives strongly enough, or didn't educate people well enough about how they can save money. While people do grumble about their electricity bill, they might not realize that there are things they can do to reduce it.
Making up numbers here, but let's say the average/"real" cost of electricity is X. To incentivize different behavior, the utility sets the price for peak hours to X+20%, and drops the price during off-peak hours to X-10%.
They observe behavior for a few months. No meaningful changes in behavior. That just means people value their ability to not think about when they use electricity more than they value the cost savings.
So, set the incentives harder. Set peak hours to X+60%, and off-peak to X-30%. Observe behavior for a few months. Maybe people will start changing their behavior now.
Unless electricity is actually that much more expensive during peak you're falling into the trap of simply artificially making the world worse for the purposes of controlling people's behavior.
People aren't stupid and will immediately recognize when the prices aren't connected to reality and resent you more than change their behavior for you. Most workers don't have access to cheap electricity because they're not home during the daytime hours, and setting up an elaborate series of timers is a non-solution.
You'll never get people to vote for the "everyone's electric bill goes up because fuck you for having a job" bill.
This is definitely the case - if you have a time-of-use tariff and an EV you charge at home, there's a strong incentive to schedule your charging to the cheapest time of day.
> However, I don't know how much consumers can do about this apart from buying batteries
If one has a water boiler or a heat pump with a buffer, they can run it at full load during cheaper periods. If they have an EV they can also charge that.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
A company called Ice Energy manufactures the Ice Bear, a unit designed to work alongside a traditional air conditioner. Like the large system used by Credit Suisse, the Ice Bear is designed to run indoors and at night, when temperatures and energy costs are lower. Ice Bear creates a block of ice at night that cools the refrigerant during the day, rather than running the refrigerant through a condenser (at peak hours) that requires a lot of energy.
Underneath the Jordan Quad Parking Lot at Stanford University, 360 miles of piping run through a four-million-gallon tank of water. At night, subzero ammonia -- a common refrigerant -- runs through the pipes, freezing the water into giant blocks of ice. The system, which is one of the largest of its kind in the United States, sends cold water from the melting ice throughout Stanford's campus, cooling buildings from noon to 6 p.m. When the facility was first built in the mid-1970s, it skipped the ice stage, instead directly cooling water that was piped through campus. A $22 million renovation -- completed in 1999 -- converted it to its present form, which saves the university a reported $500,000 a year on energy bills.
This is a great post. Thank you to share. How do you know so much about this Stanford University system?
> A $22 million renovation -- completed in 1999 -- converted it to its present form, which saves the university a reported $500,000 a year on energy bills.
So, it takes at least 44 years to repay? This sounds like a terrible investment. Normally, energy saving projects repay themselves in about 7-10 years. Also, this system sounds incredibly complex. What is the annual maintenance cost? Surely greater than zero.
I am aware of using phase change of water for various cooling purposes. Finding references again on them isn't difficult if you know what you're looking for.
Many years ago there was a green building series on KQED that featured such approaches.
Shifting when you are using energy is part of conservation.
As to how it works... it's a cubic rather than planar ice skating rink. You freeze a block of water at night, and then during the day, slowly melt it as you transfer waste heat from the building into it (rather than rejecting the waste heat with a compressor during peak energy use hours).
This is a major university, so they could be expected to be a little on the wild side with projects like that. If they're the only one with a system like that, it raises the cost.
Why? I would rather the university conserve spending to reduce cost of tuition. Instead department s of energy, for R and D, or companies flush with cash and wanting to virtue signal can splurge on such projects.
Different budgets can go to different things. Grants for X can't be spent on Y. An endowment may be for a specific goal and likewise can't be spent on some other things.
Stanford is a research institution - and some money that it receives will be going to research rather than trying to reduce enrollment costs.
Alternatively, "hey, they spent $22M on that project... maybe we should shut down the Stanford Liner Accelerator ( https://www-ssrl.slac.stanford.edu/lcls/budget.html ) which had a project cost of $315M."
There are many good institutions of higher learning out there that do not have research as part of their goal. There are 116 different community colleges within California that do not have research as part of their program and the California State University system (as opposed to University of California system) deemphasizes research. Stanford itself is a private school and not part of either of those systems.
On the other hand, people who go to Stanford often want to study under and participate in the research that is being done in a given field - and that implies that research is being done (and money is being spent on it).
Only if their energy cost never increases and the figure is resistant to inflation - 500k in 1999 is now equal to $942,584.03. There's also something to be said for the carbon emissions and the fact that we can point to frozen water being a viable system.
Thanks for this, I had never heard of qanats or wind towers.
I'm imagining a giant modern qanat running underneath a city or a large dense neighborhood and each structure reaching down into it to feed a ground-source heatpump in the cooler water like roots. Everything fed by solar panels on the roofs.
Because that's 22 million which could've bought rather a lot of solar panels and batteries, which would be more then adequate to run the system and much more transferrable in application.
Or you could invest it, make way more then 22 million over that timeframe and do even more.
Cost is a proxy for resource consumption, and in this case it seems like this was incredibly inefficient.
Edit: at current prices you build a 22 MW solar plant instead, for example.
> By creating ice when electrical rates are low and then “burning” it during the hottest part of the day, the Ice Plant saves Stanford roughly $500,000 per year and decreases Stanford’s peak electrical demand by 8 megawatts.
That's 8 MW ... you say 22 MW today, but in 1999 that 8 MW offset looks more like Solar Two ( https://www.nrel.gov/docs/legosti/fy97/22835.pdf ) which produced 10 MW and cost 58 million on 126 acres of space.
> In 2015, as part of the Stanford Energy Systems Innovations (SESI) program, a new Central Energy Facility (CEF) was built, and the cogeneration plant and ice plant were retired. SESI transformed the university energy supply from a 100% fossil-fuel-based combined heat and power plant to grid-sourced electricity and a more efficient electric heat recovery system, helping Stanford achieve 100% renewable electricity.
In Finland people have started since 2022 adapting their electricity use to shift their peak demand. But we started installing smart meters almost 20 years ago. I think the key reason to install them was less about consumer demand response, and more about saving physical visits to read the meters.
It takes some time to adapt (and also some quite extreme price fluctuation to motivate). Also good tools to automate demand response based on market prices were needed. Heat-pumps and EV chargers can now be configured to run on the cheapest hours etc.
Yup, and in Norway where 90% of new cars are electric and about 50 % of personal vehicles on the road now are electric, we're charging them a lot. Which most people now schedule to happen at nighttime to save money.
Yep, I have this with Tibber[1] in Sweden. We haven’t hugely changed how we consume electricity for small stuff, but for bigger things like car charging or even things like pyrolytic cleaning of the oven it’s easy to pick times when the prices are low, especially at the moment when electricity often goes down to near-zero or even negative.
What do you mean "was"? Every electricity provider in my country has a web interface where you can send your reading in monthly.
They send someone to physically read the meter every 3-6 months so you can't cheat, but other than that they will bill you what you declared if you send it in.
Readings are send remotely and automatically to connection provider. They pass data to seller of electricity. This data can be viewed nearly live or at most in few days online. It is all automated now. No need for anyone to go and read the meter anymore. Or even estimate consumption.
There are some special case like building where I live. Where I pay to the building, with very reasonable rate as there is no extra standing charges...
What I wonder is, who can read this consumption data besides the "connection provider"? How easy is it to drive around with a laptop and see who hasn't been home the past few days?
So basically it is uploaded to cloud and some people will obviously have access to data. Like customer support.
I think technically it is possible to listen to air interface, but either it is some mobile or some power line communication so cracking that is complex enough.
Smart meter means you do not have to do either. Meter itself can send the readings nearly live over power network or mobile connection. Thus no human needs to read the meter anymore. Saves time and trouble on all sides.
They no longer send workers monthly. Quarterly at best. Add the complications with the access into each type of building to read the meters. Also pay the worker, pay for their heathcare, when the meters can send live updates over NB IoT.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
It makes sense if you think of the thermal mass as a battery. Technology connections says he does that with his air conditioner, runs it hard overnight so it stays cold longer with less effort during the day
> Shouldn't it be the other way around? The days when electricity was cheaper at night are long gone.
Are they? Here in California most energy companies offer plans with much cheaper rates overnight for EV charging (i.e. $0.15 vs $0.45-$0.90 peak during the day).
Commercial and industrial customers account for two thirds of power consumption so there's a lot of surplus generation at night. Lots of industrial users have agreements where the power company can signal them to soak up surplus power but that's also less effective at night when wind picks up.
> The days when electricity was cheaper at night are long gone.
That must be a regional thing. In the PNW, my power rate during most of the day is twice what it is at night, and during the evening peak it doubles again.
In what markets? In most/all of the markets I can think of, night time rates are still cheaper. Even in markets with large Solar installations (CA, USA) peak rates are still during the day.
take a look at southern california edison's time of use rates. Summer day and night are the same price, but afternoon/evening 4-9pm are more expensive or you can opt for 5-8pm way more expensive.
In the Winter though, energy is cheaper starting at 8am, when the sun is out. Still more expensive from 4-9/5-8
Heat pumps use less energy when there's a small temperature gradient (assuming a good turndown ratio, cheap ones aren't so good), but they're more efficient when there's a large gradient. That's why they require careful modeling before being used for hydronic heating.
Smart meters achieve lots of goals. The most marketable was time-of-use electricity pricing.
My distribution company in Ontario makes it very clear when those times are and what the electricity prices are. On-peak is approx CAD 0.18 / kwh and off-peak is CAD 0.11 /kWh. That's over 50% difference.
The problem in Ontario, QC, MB and BC is that electricity is cheap, relative to our standard of living. The incentive to be more efficient is weak because the savings are not worth the effort.
The other reasons smart meters were installed is to speed up the meter reading process and to gather data on when exactly people are using electricity.
The electricity distribution system is passive and the grid operator has little to no visibility on what is happening at various places and times. Smart meters are the foundational tech to enable a bunch of other initiatives and planning.
Hydro-Québec, for example, allow you to see your live power draw. My meter (2011 model) can do this but my electricity distributor will not share the decryption key.
Those meters may not do much to change electricity consumption habits but they are far from a loss. The investment is absolutely worth it.
Just buy a bit bigger one, and fill the unused space with water. Every open now exchanges less air and you can turn it off for hours or a day without any impact of the temperature inside - water is good capacitor of temperature.
We fill it up with food that otherwise doesn't need to be refrigerated but they keep better at low temperatures, like fruit jams, unopened cans or olive oil. One could fill it with kimchi, beer or bottled water though.
Changing the temperature of a fridge based on electricity rates just feels like a bad idea. A lot of food can have its texture ruined by slow freezing (a common occurrence at the back of many fridges already) and waiting to get food down to the target temperature will just lead to bacterial growth.
Seems like having an ultra-chill button for that function would help with that.
Might want some phase-change materials to optimize the thermal banking.
That’s easier for a freezer (very salty water bottles) than a fridge (need some carefully produced waxes), but fridge contents should be more tolerant of temperature variability.
Would add that refrigeration is more efficient at night when ambient temperatures are generally cooler and/or heating needs are greater, so the “ultra-chill overnight and daytime backoff” might not increase consumption.
the fast chill button is a thing. it's in both my 8yr old GE and my newer samsung..I never use it though but it's made for putting still warm leftovers in and getting them cold fast
These functions do not change fridge temperature, choose when to run the defrost functions for no-frost units (a quick wall heating to melt the ice and quickly came back to normal), choose to run or not some ancillary functions (like making ice cubes) etc. They are VERY chatty https://news.ycombinator.com/item?id=38984609 but not much useful.
Shifting loads for hot water, if you have big enough reservoirs on contrary change MUCH the game, being able to shift some loads automatically, like leaving a dishwasher or a washing machines, a pumped irrigation systems and so on might significantly change the overall bill to makes investments in that sense meaningful.
A recent podcast turned me onto them. The idea is to heat water to higher temps than normal and use that extra heat as an energy store for use during peak times.
I think is not a novel idea: there are various vendors here in EU that offer "thermodynamic VMCs", meaning dual-flux ventilation system [1] with a small heat-pump between the to air flows, sucking heat from the outgoing air, heating the incoming flow in winter, in summer to avoid injecting too humid water they passively exchange outgoing fresh air with the incoming and the heat a water tank for sanitary water, cooling as needed the incoming air after the passive exchange, for instance https://www.broferpura.it/en/products/Domestic/compact06.htm... this reduce the number of compressors a home need in mild climate and new homes.
For me I simply run the main heat pump at full power during the day on p.v. reducing the grid absorption for some hours in winter and for sanitary water almost zeroing it since 300l @60-65℃ (140-149℉) suffice for a whole day, at least when I have enough p.v. a day after another.
Honestly I doubt it's possible to store enough heat with current tech to compensate the home heating needs, it's possible for sanitary hot water (except for a swimming pool) but no more. However for mild climate for some months might be enough to significantly reduce the grid absorption. The sole issue here is that heat pumps now, without any specific reasons, have skyrocketed in retail price enough to make them far less convenient than just few years ago... So the economy is still not much.
This is very standard stuff in Finland for decades. And before heat pumps became popular large tanks were common and those were heated during the night.
Most freezers already do a defrost cycle so could probably play with that. It’s only a few degrees oscillation so idk how much savings you could get there.
A modern fridge only consumes around 350kW a year or so, so any savings are going to be modest. It would not be the first target if I wanted to cut my power usage, especially if the consequence was going to be more freezer burn.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
I don't believe there would be many if any cost savings from doing this. The engineering thought behind it would cost more than the actual savings. It would make a lot more sense to buy a chest fridge which I imagine uses half or less the energy of a typical standing fridge.
Department of Energy / EnergyStar state 50% energy savings for freezers. Freezer/fridge might not translate perfectly but I imagine a fridge is getting opened more often during the day which would skew that even more towards the chest being more efficient.
Wow. That is a surprising number: "An ENERGY STAR certified chest freezer uses about 215 kWh of electricity and costs about $30 per year to run, while an ENERGY STAR certified upright freezer uses about 395 kWh of electricity and costs about $60 per year to run."
When you open the chest freezer, you don't have cold air "spilling" out of it. It remains in the chest.
On the other hand, when you open a freezer that has a door on the front, a substantial portion of the cold air spills out of it.
When freezers are coupled with refrigerators, the way that many of them work is by having the freezer air descend into the refrigerator through baffles (which again, makes the freezer work to cool the air that was exchanged with the refrigerator).
If it's a freezer you use often, it's worth considering upright, because you want to be able to see, access and use most of the freezer, instead of just the top.
Add to it small humans who may do the same and the $30/year in electricity differences can be dwarfed by the benefits of having a freezer contain meal prep, etc.
Combining a small standup freezer with something like a Foodsaver is an easy win to reduce waste / thrown away groceries, as well as helping with off-season wishes.
Buying less from the inflation fuelling large grocery stores is something that is well within reach.
Chest freezers are less convenient to access, and require different accommodation than an upright refrigerator.
In a chest freezer:
- You access everything from the top. This would require something like a section of cabinetry which opens to the top, or a chest freezer occupying kitchen or other living space. Since the freezer is low and wide, this has a larger floor footprint than an upright fridge.
- Contents are stacked vertically, which means you have to dig through the pile to get to items on the bottom. There might be designs which make this easier (e.g., fold-up shelving), but that would have to accommodate another aspect which is that ...
- Chest freezers tend to frost over fairly heavily. Cold air doesn't spill out, but warm air tends to settle down into the fridge, and as it chills, loses its humidity as frost. Many or most chest freezers don't have an automatic defrost cycle,[1] and frost will build up on inside walls, contents, and any moving parts such as the fold-up shelving I'd described. Defrosting is typically done manually with chest freezers.
- Chest freezers are, well, freezers. I suspect some might be able to operate as refrigerators, but AFAIU they tend to cool somewhat unevenly as refrigerators rely on active air circulation to cool contents and avoid hot or cold spots.
If you're aware of these limitations and/or can work around them, e.g., by having a trundle-shelf or top-access countertop to address floorspace / footprint issues, and can find a way to easily access contents, chest-type designs can be a good choice.
________________________________
Notes:
1. Refrigerator defrost cycles involve halting the cooling cycle and activating heating elements in the refrigerator (and freezer-space) walls to melt any accumulated frost. This itself is both a considerable energy expenditure, and tends to accelerate freezer burn and other ageing of food often giving unpleasant taste or texture.
We have two chest freezers and an upright freezer. The chest freezers outlast the upright freezer, and there's no shelves* to get in the way of optimal packing.
*However, you have to unpack when you want something from the bottom. This is why we have an upright freezer. We store cheese curds from our dairy in it, and we want to access them quickly and easily and regularly. Also we use ice packs for shipping, and the shelves make it easy to freeze ice packs flat.
And it can easily become essentially a black hole. Not that that doesn’t happen with my upright too. I’m split on whether I shouldn’t just have bought a chest freezer when I bought my spare freezer.
I'm in BC, with BC Hydro. The smart meter means that everyone can see their own daily usage and trends. I'm sure most won't look, though I do. What I found more useful is the paired device from Rainforest Automation, e.g. https://www.rainforestautomation.com/rfa-z114-eagle-200-2/.
I had to buy this, but it's paired to my specific meter. Basically it gives me a means to see my overall usage in real time, so that I know how whatever we are doing, affects the usage.
BC Hydro has had programs such as a voluntary one, where you get an email about a 3-hour period the next day. They'd like you to drop your usage for that period by 20%, and you get a few dollars per successful drop at the end of the season. With our heat pump for heat, we just switch it off for that time, and skip using the clothes dryer then. At the end of the season, we got maybe $50 off our bill in credits.
They have proposed a time-based plan, with discounts for night-time. I have not elected to try that out, because it also came with penalties for daytime usage.
I'm in Ontario. 90% of my electricity usage consists of charging my electric car. The ultra-low overnight rate of 2.8 cents per kWh, introduced during the past year, is a big win for EV owners. This rate is seven times cheaper than the cheapest rate mentioned in the article, and ten times cheaper than the peak rate in Ontario. It is very, very easy to schedule your car to charge during overnight hours if you have a home with a garage. You better believe that smart pricing has shifted when I charge my car! I think this kind of benefit will become more pronounced as more people shift to electric vehicles. People won't shift demand for small appliances, but when 90% of your usage is made up of one single thing that is easy to shift, you'll get some returns.
that you own a garage, that your electric bill is in your name, that your driving distance makes this worth it, that your other electric consumption is small and so on. It works for you, that's great but something you didn't mention is the higher on-peak rate.
If you have electric heating or need to charge your EV during the day, the increased rate there can easily offset your overnight rate savings.
These assumptions are not at all unreasonable. We are not talking about a tiny minority. More than half of Americans have a garage. Utilities aren't concerned about individual households; they're concerned about average behavior. I'm just guessing here, but my guess is that if even (say) 20% of households do what I do, that alone probably makes it worth it.
I drive about 15000 km per year, almost exactly the Canadian average. There are a lot of potential households fitting this profile.
(If you're needing to charge your EV during the day, then the higher daytime home electricity rate is irrelevant. My EV has a 300 mile range, which is typical. I cannot think of any scenario where I simultaneously 1) drive 300 miles in a single day, and 2) somehow also remain close enough to home to charge at home, so that the daytime home electricity rate matters, and 3) can't wait until the night to charge.)
There aren’t a ton of smart appliances because there aren’t a ton of smart grids. We need smart grids with, like, really significant demand based pricing before people are going to care about smart appliances. And of course there’s no reason to get smart appliances if you don’t have that kind of grid.
Somebody has to go first. In the bright side it really is unambiguous whose job it is. Utility providers are often government subsidized or at least heavily regulated government-provided monopolies. They have the responsibility to act in the public good, and provide strong enough incentives to get people to come along with them.
We’re close to this. California, which is not the world but is a major market, has pretty transparent grids with variable pricing. I don’t know if they’re “first” but they’re a big enough market to drive change.
Electric Cars use a ton of electricity and have these sorts of features for a while now. Apple even built grid pricing info into their latest “Home” app for California users.
I think there aren’t smart appliances because there is no demand for people to change their behavior. No one is going to put off cooking dinner for cheaper oven use. We see it with cars and smart thermostats because it’s largely set-and-forget with people.
We should slowly expand what “set and forget” means. Dishwashers and clothing washers for example, we could modify our behavior a little bit without any major inconvenience (load it up, put in the soap, and then let it schedule itself, you’ll get a notification when it runs).
Ovens and stoves are, I think, an unusually bad case. Although, slow cooking should be shiftable, right? Maybe we’ll have to eat slow cooked ribs instead of hamburgers. You know, to save the planet or whatever.
Instant pots, kettles, dishwashers, microwaves and toasters all reduce energy consumption to do the same thing, but I don’t think anyone bought them for those reasons.
The most effective method to reduce/shift consumption is just to make it the easier way.
Adding cognitive load to shopping decisions and their daily lives is predictably ineffective for the general public (and almost universally hated).
That majority will be a bit poorer because of it, and many will cheer that aspect but it also means the target goal has failed.
Gas has its own set of issues, from terrible leakage in every stage of distribution, to microparticules during cooking (which directly affects the health everyone that lives in the household), going through the ecological impact of production, and without forgetting the really bad failure mode they have when buildings fail in areas prone to earthquakes.
The savings made on meter readings, the reduction in meter breakdowns, the detection of illegal connections and other factors alone justify the renewal of electricity meters.
The linky meter can also be remotely controlled to reduce the maximum power delivery for bad debtors (it's very rare in France for electricity to be completely cut off).
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
If you are a bit technical, you could convert your fridge into a smart fridge that does exactly that.
Throw a temp sensor into the fridge, set the fridge temp to as cold as it will go, then plug your fridge into a smart plug. From there, you can monitor the interior temp and turn on the fridge based on when you want to super chill. Dead simple to do something like this with home assistant.
Don't blame it on the smart meters, blame it on the governments that refuse to structure the plans to take advantage of it. I figured it would be a no brainer to switch to the time of use plan because we have an electric car we charge at night, but no, the standard non time of use plan is cheaper for us.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
Maybe just use a freezer and put it on an old school outlet timer? Run it at night and treat it like an ice box during the day.
My house moved to smart meters over a year ago. Still get the one total usage amount per month. Even if I log in online there is no way to see what I use even per day.
I do think we need to have a price that changes during the day but I suspect most people wont tolerate it and the politicians wont allow it.
My fridge (some LG models supposedly does this. I say “supposedly” because this requires connecting to Wi-Fi, which I don’t want to do, but in their the energy company sends it signals about how the grid is doing and the fridge goes into energy saver when appropriate.
A nice little vlan with only internet access would let you connect your fridge to your WiFi without worry. Most WiFi + router combos come with a Guest vlan which already does this out of the box.
ahh you are correct, I was conflating 2 things..however it's called a smart grid fridge and it pulls dynamic pricing from the elec provider and does the optimization on its own
In my mind, the smart grid would be most useful for distributed storage. Like if your car charger has a battery pack in it to quick charge your car. Or just a battery that could charge on off-hours to lessen peak load.
>Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
you put a backup battery system in between your house and the power grid, switch power hungry appliances to battery during peak times.
over a long enough period this should achieve what you're looking for and is the most likely solution to "force" people off the grid at peak times.
it's just that right now where like you said - why bother when all you're saving is a couple hundred bucks? spending that mental energy on things that will earn you money is better.
Your fridge doesn't need to know energy prices. Fridges are for cooling, not computing your bills, and giving them access to too much data only encourages the usual IoT vendor abuse patterns. It should be enough for it to get a proxy signal. "Cheap tariff" / "expensive tariff". Or maybe continuous 0-1 control signal. Optimizing energy use for household or building already requires an external decision-making center anyway.
It could just be telling it what your time-of-use rates and hours are. I think most places with variable rates at this point are on a schedule that does not often change, only a few places have completely dynamic pricing that would need real time information from the grid operator.
Generally Time of Day electricity billing is just an average costing at fixed windows of time. 2-way (or really, just 1-way is actually necessary) comms not required.
Not too common to have totally dynamic pricing. And even if you did, they have general trends.
I did a project with a french Linky a few years ago that used an ESP8266 to grab the serial data stream from that exposed port on the bottom and log the interesting line items it prints out to a InfluxDB timeseries database running on a local server and use Grafana to get a dashboard of various metrics.
I remember having to do some sleuthing with the serial port as it wasn't something standard - it was like 7 bits, no parity, 1 stop bit, or something like that. And a small circuit to do level shifting for the ESP8266.
The result was data on wattage draw approx every 1 second. This allowed for some very, very fine analysis in the data.
I tell people about this when I talk about various sidechannel attacks on things that use data like this- for instance, after observing the data for a while, I could tell which floor of the house someone was on by watching transients of the wattage and the quantized changes of various devices turned on and off - e.g. the kitchen has a kettle that uses 1220 +/- 5 watts, every time, and nothing else in the house results in a step change of that value. The top floor bedroom has lights that use exactly 42 watts. The laundry machine starts up with a very specific ramp and then oscillates between two levels of power with a period of 30 seconds, etc.
You can figure a lot out about the movements of people and what they are doing by simply having fine enough time resolution on a single number - the total power consumption of the entire house.
Indeed, and to be fair most people I know who were reticent to the new Linky were not "fearing that the new meters would fry their brain using Bill Gates’ evil 5G Wi-Fi waves", but were concerned about their privacy.
In Finland (and I guess at least other Nordics as well) we are starting to get neters with so called P1-port, which is open for the user to get their data. All I needed was a wire with RJ26 and an ESP8622 with some esphome definitions and now I get all kinds of data from the meter every 4 seconds. Total consumption, consumption, amperage and voltages per phase etc.
In Germany we have an infrared one-way connection (SML protocol). I hooked a Raspberry Pi Zero WH (consumes only 0.7 Watt) with Ethernet Hat and USB-Infrared-Reader-Cable to the Smart Meter. The PI reads and transmits all readings over MQTT to my InfluxDB 2.0, which is running virtualized on Proxmox. At the same time, I also read my solar inverter through Modbus TCP (via OSS called "Solaranzeige"), to the same Influx DB. Both is visualized in Grafana. It is a nice stack that did not produce any problems in 7+ years.
All of this helped me to better understand my electricity consumption.
This is a great post! Did you blog about it? I am sure HN would love a post like that. I would generate lots of interesting convos around similar setups in different countries.
Ah, you mention a pain point. It's on my list for years now.. I've just added 60 kWp Solar plant [1] to my existing 30 kWp; once this is through, my monitoring stack will need updating and I will blog about it here [2].
The port/protocol originates in Netherlands and is getting widely implemented across the EU. It is really nice that the port provides power (esp. in recent versions) for an ESP, so you don't need to worry about bringing power to where your meter is (which may be outdoors.)
Yeah, P1 has been around for a decade or so in the Netherlands. If don’t feel like setting up an MCU yourself, Homewizard Energy is pretty good. I don’t use their services, but you can enable a simple API on the local network that gives you a JSON representation of the ‘telegrams’ that come out of the P1 serial port.
Oh yes, now I remember reading the P1 spec and it does indeed say that it has been in use in the Netherlands for many years already. In Finland we also call it the HAN-port or the H1-port. Also, I must clarify that it uses RJ12, not RJ26 which I don’t even think exists.
The HomeWizard stuff is great. They also make a water meter, separate kWh meters in 1 or 3 phase and smart plugs.
If you have a subscription to their service, they can be programmed to eg turn on when there's excess solar power etc.
And integrates with HomeAssistant.
I thought the old meters were all bidirectional (ie: the spinning wheel could go backwards if you back-fed). Dunno what older gen “smart”meters would do. But I guess the newer meters are capable of paying you some reduced/enhanced rate for backfeeding?
I have my dumb electricity meter sending my electric usage to google sheets every one minute
I used an ESP32 with a very basic light sensor, the sensor was blue tacked over the 1000th/Kwatt LED (this blinks 1000 times per unit of electricity used) the info is sent it over my wifi to google sheets
it also records the sum per hour indefinately, or until google sheets complains
The UK has smart energy meters for a lot of customers. Octopus are an energy supplier which is using them to great effect for data nerds and people who want to save money.
To get the data out, you can just call their API to get daily consuption figures, split into half hourly blocks[0]. They also allow you to just download a CVS file directly from the energy use section of their website.
The data in the API is only update daily, but they can give you a tiny addon device[1] for free which will allow you to access live usage in realtime (updates ever 10 seconds I think).
I use a Home Assistant integration to collect all this data live there.
To make use of the smart meter, they also have a series of tarrifs which change price dynamically. The simplist is Tracker[2] which charges you a different price per unit every day based on the wholesale price. There's also Agile[3] which is the same concept but the price changes every 30 minutes with higher highs and lower lows. That one is great if you can shift your energy usage outside of peak times.
They also have "intelligent" tarrifs where you allow them to control your car charger[4] or home battery[5] so it charges when it's cheapest.
Octopus are doing really great things in the UK and part of their business is that they sell the backend as a service to other energy companies who were previously stuck in the stone age as Kraken[6].
Octopus is currently trying to set up in France. They've got a pretty amazing advertising campaign where you don't know what they're selling except for a pink mascot.
Alternative suppliers to EDF have a very bad reputation in France. Their contracts are often unclear and subject to major price variations (+100% after the start of the war in Ukraine). Some use unscrupulous prospectors who take advantage of elderly people to get them to change their contract (Total Energy, I'm thinking of you).
The majority just buy Mw/h from EDF to resell and speculate on future production contracts. They don't invest a single euro in production facilities.
The founder of Octopus was from a software background and has claimed that Octopus (the energy company) was initially just to demo the potential of the software.
Ironic that their software is so terrible then - it took over two years for their support to do 'something' to my account so I could actually pay my bills.
Their hiring is awful too, they took 2 months to get back to me with feedback on my takehome task. I'd already been in a new job for three weeks when they finally came back.
I would love a way to turn off my electric hot water heater between the hours of about 10pm and 7am.
I see no reason to keep the water hot during the time absolutely nobody needs it, and we know it will take less energy to heat it back up again rather than keep it at temperature.
Also, yes, I have turned the temperature down as low as it will go.
The box has a 240 volt circuit and a 120 volt circuit into it. The 120 volt circuit is connected to the programable timer light switch, which is then connected to the control inputs of the contactor.
The 240 volt line connects to the contactor and then on the other side of the contactor it connects goes out of the box and to the water heater.
For me I've programmed my hot water heater to turn off from 4pm to 11pm on weekdays, which avoids heating the water during peak time of day rates at my location. (I typically shower sometime during that period.)
I can open the box and press the switch on the timer if I ever want to temporarily override the program.
That all said, I don't have any measurements to tell me if it is worth the expense. Although it is quite clear from my hourly power usage when the hot water tank switches on at 11 pm.
On weekdays, my price of electricity from 11pm to 7am is about 4 times cheaper than from 7am to 4pm, and about 10 times cheaper than from 4pm to 9pm.
Also I usually run the dishwasher and laundry sometime after 11pm, so it is usually helpful to have hot water available overnight.
Edit: I should mention that I have a ventless combo washer/dryer, so my clothes come out clean and dry in the morning. Unfortunately they are not folded.
To understand how this works it's important to know that temperature loss is linearly proportional to the temperature difference. Insulation reduces the ratio independently of temperature.
As an approximate example, suppose if takes one hour for the tank/building to reduce to a thermostat set-point 10% lower than the 'high' set point. Further assume you could use that lower set point for 11 hours, so the tank/building temperature is 10% lower for a full 10 hours. Finally, assume increasing the temperature of the tank/building by 10% takes one unit of energy.
In order to maintain the low set point, the first hour is free since we are losing temperature. The middle 9 hours need (190%) = 0.9 units per hour for a total of 8.1 units. In the 10th hour the low-set point scenario needs to warm up to the high set point and overcome heat loss so that individual hour requires more energy than the high set-point scenario: (1110%) = 1.1 units for that single hour to return to the high set point.
In total the low-set point needs 0 + 8.1 + 1.1 = 9.2 units of energy over the 11 hours.
For the full 11 hours the energy required to maintain the high set point is 11 units (1 unit per hour to make up for 10% loss).
Insulation is worthwhile, but has nothing to do with what you are asking.
If you are heating a house, or a water tank, or anything, it requires much more energy to keep it at a constant temp 24x7 than it does to let it cool down when you don't need it hot, and then just heat it back up again later.
That is why "smart" thermostats like the Nest became so popular. No need to heat your house while you are away during the day. So let it cool down a bit, then just warm it back up again soon before you come home.
Much less energy used.
That fully depends on the level of insulation. Newly build houses here in The Netherlands rarely cool down when heating is off, and the temperature stays generally stable, even when you are out (and the heating is off).
My Quooker is so well insulated, that you should only turn it off if you aren’t home for a week. Otherwise is exactly counter to what you say: more energy efficient to keep it at temperature instead of letting it cool and heating it again [0].
No, that is still not true, no matter how good the insulation.
> That fully depends on the level of insulation. Newly build houses here in The Netherlands rarely cool down when heating is off, and the temperature stays generally stable, even when you are out (and the heating is off).
Even if it's a few days, and it does drop a few degrees, you still spend less energy bringing it back up to whatever temperature than you would have to keep it there the entire time.
Do you have anything to support that claim? Because in my belief this follows normal thermodynamics, which means that if the energy dissipation over an amount of time is less than the energy cost to heat, it makes sense to do it.
Do you think there is no relation between the thickness of the insulation and the time it takes before reheating is more energy efficient?
If it’s larger than 40A @ 240V, you could buy a 120v astronomical time clock switch and use the output of that as the input to a 120v control coil for a contactor sized for your water heater.
Per @quickthrowman recommendation I can add that this is the way to go for an electric hot water heater having installed many of these Intermatic time clocks. The old ones were analog and one can hear a clicking but they do make them digital now, YMMV.
I use a $8 programmable plug timer switch off Aliexpress to do exactly that. But it's only useful when I live alone. When a girlfriend is living in, messing with hot water supply is an absolute no-no!
Depends… if you like to take your showers at peak times, the tankless might cost you more in opex (in addition to the capex).
More and more “tank” water heaters are moving to heat pumps which should use less electricity overall than a tankless (if you can handle the possibility of running out of hot water).
Which if you go that angle the capex on a heat pump heater regardless if hybrid or pure electric is going to negate any savings, those are typically 2-3x of a higher quality brand traditional water heater.
Which full circle going back to the original discussion of turning off the heater. You probably end up close to no/low savings. I can see an argument of a smart heater being able to slightly adjust load at peak times but I engineering a heater to turn off when you are sleeping and then heating back up before use is probably going to not have much savings. Those heaters are increasingly made to edge out at maintaining the heat and take quite a few hours to heat up.
The cheap ones are fairly common in Britain where the user isn't choosing (student houses, cheap rentals etc). The installation cost is low, but the running cost is high.
They are crap. 8kW is typical, and the pressure for a reasonable water temperature is low.
I haven't knowingly used a more powerful one. I suspect that would negate the cheap installation cost, as it would need a three phase circuit.
Yes, You can buy an electric tankless but just be extremely informed of the large amperage requirement to instantly heat your selected gallons per minute flow.
Yeah you can find them on the Home Depot site. The largest ones use 36kW which is beyond a typical residence's electrical service. It doesn't save you any money if you need to upgrade your electric service.
A few years back I had a Sense power meter installed and its been great. It took some time to configure and get used to, and for it to detect various devices, but now I can reliably predict my upcoming power bill. And make adjustments as needed.
Whats helpful is it shows the top power consumers. And by paying close attention to that I've cut my bill by at least 1/3.
One project I worked on was to track indoor temperature and AC settings (via a Nest thermostat) and outdoor temperature (via weather report). I found that in the evenings I was often still running the AC even though outdoor temperature had dropped below my target. This alerted me that I should instead open my windows. I didn't have a way to track energy usage changes, but I was really happy to get so much more fresh air.
It stopped working when Google bought Nest and then changed their API authentication method. I had a newborn and just couldn't find the time to support the new API. Maybe I'll revive it this summer.
I've been making the same mistake. Another thing to note is warm air can pool in corners, so reversing fan direction or pointing a fan at corners helps
- fear and polemics about connected meters was not about "surveillance" by some giant but more about ability to disconnect or throttle a customer from remote and third party monitoring to elicit family habits for instance to organize a burglary;
- reading the meter without the need to get inside the home was already a solved problem with "telereport", a small local dedicated bus with wires going in some public places (like the hall of a condo, a small box near the portal of a home etc) who allow local reading, this could be used to send data remotely WITHOUT adding extra abilities like throttling or disconnecting;
- polemics exists for similar reasons for IVRE norms (BEV domestic charging) where the norms demand a kind of "remote control" to allow disconnecting the load from the grid when needed by the grid, without considering the few but not so few with domestic p.v. in self consumption that might get disconnected as well because there is no analysis of the grid absorption load just a "run this if the grid is strained";
- `Enedis website is nice` is well... debatable...
Beside this small notes NOT intended to diminish the author creation, IMVHO monitoring is useful only if you can act, for instance with p.v. and controllable appliances it's a good thing, and unfortunately there is next to none appliance really designed to run on p.v. when available, even 99% of those who claim the contrary. The first are domestic water heaters who actually could be piloted to shift load with HA/Shelly/* sometimes just abruptly cutting the power and giving it back when there is enough p.v. but not much more, secondary running dishwashers and washing machines left loaded and ready in a "run before 'given date and time' preferably on p.v. power" and so on. Technically such automation are damn simple and cheap if designed as part of every appliance but so far next to no one seems to be doing so, while mandatory monitoring and published monitoring solutions are more and more pushed. Personally having p.v. I do my best to shift loads and it's damn hard, mostly limited to smart switches connected to HA, because there is not much more to do. I can "hack" my dishwasher or washing machines, are dumb and basic enough to be easy just seeing their small controls and replicate them with a some GPIO on a raspizero and alike but that's a long uncomfy process since every machines have it's own controls and you have to redo when you change it. There is no standard.
Wouldn't it be cool if every wall and ceiling socket could report its electrical usage? I wonder if that's possible via powerline networks, or if it would work over something like Zigbee?
ZigBee could definitely do it but as someone with a lot of smart wall plugs (I have a total of ~40 ZigBee devices in my house) that data is just not really useful because it's just a drop in the bucket compared to cooling/heating/hot water.
One thing that would be more useful and that I really want to get is one of those amp meter for the distribution panel to see my power consumption in realtime: https://www.aliexpress.com/item/1005007038134809.html but I didn't get around to it yet.
I have two of these(1) Emporia Vue2 units in my home, one in each load center. I have them flashed with espHome and integrated into HomeAssistant.
I really love that they give whole home power usage, as well as up to 16 individual circuit usage details. And with espHome into HA, all local control with no cloud dependency.
This is what I've done; I use a Z-Wave power meter on my electricity meter for whole-home, then some individual ones for my desk/3dp/rack, the ~50 ZigBee devices I have are mostly bulbs or sensors (I also have another ~40-50 Z-Wave devices) and the majority are things that use very little power; the usage stats from those things is a rounding error.
For bulbs and sensors, the power usage isn't useful for automation either, you can use other data they provide (turn off lights when no one is around, do stuff when doors open/close).
For whole-home though, it can be useful to see if the power is higher than you'd expect; if it's not dinner time and we're using 2kW+ for more than a few minutes, send a notification in case someone left an electric heater or an iron or something on.
I'd appreciate smart plugs with bidirectional communication, as real-time power use report + ability to switch the plug = poor man's way to turn most devices into IoT devices for local control. It would help in particular with ones operated by IR remotes, which deliver commands but don't get feedback on their state; you could observe device's power consumption to infer the current mode of operation, providing a bidirectional control abstraction in e.g. Home Assistant.
I used to work closely to this on whole home energy disaggregation. There are products for doing this, but the value is very limited.
Excluding EVs, heating and cooling is the largest factor for energy consumption followed by other large appliances. Small appliances and electronics don’t use much electricity or aren’t on long enough to matter.
If you’re interested in some product recommendations, the Sense Energy Monitor used to be a popular choice. Basically it is a set of clamps that you can attach at your breakers to monitor specific circuits. It’s good for monitoring large appliances with their own dedicated circuit. For individual appliances, a Kilowatt Meter works fine. If you want something for continuous monitoring long term, I’d look at the Eve Smart Outlet.
I have a Sense Energy Monitor. It works pretty well, but I wish they made their own smart outlets to integrate with the panel monitoring.
Anyways, some pretty clear trends emerge when tracking your energy usage. Climate control (heating, cooling, fans, dehumidifier) dominates my energy usage, then EV charging, the kitchen stuff (refrigerator, cooking, dishwasher), then electronics (and I have a ridiculous amount of them), clothes dryer and lighting. I would like more insights into my electronics for personal curiosity (which Sense can't seem to do), but in the scheme of things it probably doesn't matter. No individual electronic device is going to make much of a difference.
Not quite every socket, but iotawatt can monitor each circuit at the breaker panel, and from there, it's generally not too hard to figure out what's going on, and it's really nice to be able to get a concrete sense of where your electricity is going (for most people with a heat pump, it's mostly the heat pump, it swamps even our EV). It's local-only, no cloudiness, and it's been rock-solid for us.
This sounds pretty cool. I just went through the docs but I can’t tell physically how you install the CTs. Our mains come into the house underground and into the electrical panel and of course the wiring is all in the walls. Are you supposed to open up the walls and attach the CTs to the wiring in the walls? How would this even work for Romex that runs along framing?
You just turn off your main breaker, open up the panel, and snap the CTs/current transformers around one of the wires on each circuit (you can open them back up if you mess up). You only want to put one wire through, rather than a full romex bundle, because it measures the flux through the loop, and the return path would cancel out the reading.
It does take a bit of reading to figure out eg what to do with 240v circuits (you can usually double it if you don’t care about absolute precision, usually one leg has the control electronics on it and is a bit higher). Also, it doesn’t have quite as many channels as most panels’ max # of circuits, so you might have to choose, or try to run multiple wires through one CT.
If you’re uncomfortable with going into the panel (reasonable), you can probably find an electrician that’s willing to put it in/make it pretty.
I think I saw some YouTube videos of people installing them diy before I tried, that might help get you more comfortable with the process.
You can definitely do this with ZigBee, I have smart light-switches that report usage; though I'd argue the lights are the least useful thing to have usage reporting for, since I already know the power consumption of the bulbs, and since I'm using LED everywhere, it's negligible compared to the rest of my usage.
The problem with ZigBee is network scale and interference, but also you're wasting energy by having electronics in every socket, always on, always reporting. You're also then driving your server harder and storing more data, costing more.
I've aimed to strike a balance of only making smart the things I actually care about power usage for; my server rack, my 3D printers, my desk, and then whole-home as a single unit.
I don't need to know how much my washing machine or oven uses, if I need to use them, I need to use them; there's little room for optimising.
When it comes to optimising which settings I use, if I care enough, I can use a temporary ZigBee power meter that plugs in like a normal device; record data for days/weeks/months and adjust based on the result of that.
Exhaustive data has nerd appeal, but in practice, you'd add power, circuitry, and RF noise overhead to mostly see signals that maintain very stable patterns for as long as the same thing is plugged into it and used in mostly the same way (i.e. for months or years).
All you really need is snapshot understanding of what a device really consumes, and only then if it's non-negligible and some alternative might make sense.
For outlets and receptacles, you can achieve that by just inserting a meter where you want. Per-circuit metering in the distribution/circuit breaker panel would be nice though.
There is a company that does this but senses direct from your circuit breaker panel. The uses FFT plus algos to determine individual devices on each circuit from their unique electrical signature. Called Sense I believe. I’ve never used it.
if only! i know this is not what you’re asking for, but inexpensive Sonoff outlets flashed with firmware and reporting to Home Assistant are how i monitor (and switch on and off!) the largest consumers of electricity in my home. it’s a good two-weekend project
Not sure I really agree with all these design choices. The color scale on the hour/day grid initially seemed backwards to me. The daily total takes up so much space that it would be better as a normal line or point graph with scaled axes, instead of trying to guess the correspondence with the color.
Aside from that I am curious about the discontinuity at 22h. How many and what kinds of loads automatically respond to these price signals? Just heaters and water heaters?
> Aside from that I am curious about the discontinuity at 22h.
My water heater turns on during off-peak hours (so, at 22h). I have no other equipment that responds to the off-peak signal, so the discontinuity is entirely attributable to the water heater.
> The color scale on the hour/day grid initially seemed backwards to me.
I think it was one of the default color scales in Plotly. Maybe I got used to it, it doesn't strike me as reversed, but I think I see how it would feel that way for you.
> The daily total takes up so much space
That is true, though it didn't disturb me enough to bother changing its size.
Question for experts: I'm on SDG&E (North County San Diego) and apparently have a smart meter that supports HAN at 900 MHz, but at the end of last year SDG&E declared "no new devices [HAN devices] can be connected". Does this mean that if I want to monitor my electricity use that I’m out of luck?
SDG&E supports "Green Button" downloads, but I wonder how long that will last — the links in the "Apps" section of https://www.energy.gov/data/green-button are dead, the official GitHub repo and Green Button Alliance repo appear to have gone into a coma around 2015, and Wikipedia doesn't have an entry for it.
If you live in the UK, you can sign up to https://glowmarkt.com/ and they'll give you the same 30 minute time slices, or you can buy one of their in-home devices for £70 (https://shop.glowmarkt.com/products/display-and-cad-combined...) and it'll push your usage every 10 seconds to MQTT to give you very interesting if completely useless graphs in Home Assistant.
How is this sustainable as the gap between self generated and stored energy and the grid price continues to diverge?
If present trends hold it won't be long before a few years worth of energy bills even in Europe finance a full off grid deployment. There doesn't seem to be much room to cut on the energy companies pricing which remains variable and pointlessly complicated vs "I bought this off grid system and now I never think about energy anymore".
Just people in high density housing, people in a lease, and those who can't afford the up front cost will constitute the majority of residential grid energy usage and purchasing?
Other than southern Spain, France, Italy and Greece, you're not going to run off-grid anywhere in Europe. Too little sun in the winter for heating needs. Unless you're considering small-scale wind power installations, but I cannot imagine what costs those could incur in installation alone.
Up in Orkney on vacation, the pretty constant wind all year (according to relatives) with a little solar, battery storage and heat pumps, I reckon off-grid might be possible. Add in starlink for internet and I might just stay here.
Not sure of the cost (need to do the research) but all of the above are getting cheaper. A small wind turbine can’t be that costly, surely.
Wind turbines in my research are pretty terrible unless run at scale (massive). YMMV but when I last looked into it, small turbines tended to be 1) noise polluters, 2) not very large power generators and 3) poor build quality.
The dilemma with wind turbines is that the small ones tend to be inefficient (and still much more expensive than solar), and large ones require huge up-front investments.
I'd love to be proven wrong about this though, if anybody has links to affordable wind turbines / generators, I'd be interested.
When I’ve looked into this before for a client in Scotland, it seems the smallest size that made sense in terms of the factors other commenters have mentioned was about £50,000 to install. Also it requires planning permission which is much harder to get for a wind turbine than for solar PV which you can often install without getting explicit permission under ‘permitted development’ rules.
You can run a generator to charge batteries or provide additional capacity when needed.
It would be ideal to have full coverage with "renewables" (isn't oil and gas a renewable just on a longer timeline?) but don't let perfect be the enemy of good if you want to move off-grid.
I do lack familiarity with the European environment, but between geothermal, wind, hydro and natural gas backup, is it really feasible as it is in places where solar gives 0.01 USD kWh prices?
That vicious cycle is a problem ever more expensive electrical grids will need to contend with over the next couple of decades.
The variable per Kwh costs are historically generally pretty low relative to the fixed capex and opex (eg. maintenance, idle runtime) costs.
Mostly this has been made palatable for residential use by hiding these fixed costs in a higher per-Kwh rate. This works great as long as consumption is high and growing. If consumption trends reverse, then self-generation becomes a real possibility for the heavy consumers leaving fewer total Kwh to spread the fixed costs over.
Left unimpeded this leaves the poorest with very high energy bills when everybody else has shifted to a private, cheaper, micro-grid.
Self-consumption can be envisaged, particularly for buildings with air-conditioning systems. In this way, you pay for part of the air-conditioning consumption with solar energy when you use it most during summer.
But operating completely disconnected from the grid, especially in winter, is extremely difficult. Luminosity is much weaker, the sky more overcast and the number of hours of sunlight reduced.
Anyone here use the NiceGUI Python web app framework the OP used? There is mention of Electron-like cross-platform ability, which I assumed meant that one could generate a standalone app with it, but I did not find mention of that in the online docs.
You can get your data from the edf.fr site. In your account, under "Ma consommation d'électricité" there is a button "Télécharger mes données". It comes as a zip of csv files with daily and monthly values.
Yes, Con Ed now has smart meters that report electricity usage in realtime at 15 minute intervals. If you use Home Assistant, you can perhaps make use of the Opower integration to get this data: https://www.home-assistant.io/integrations/opower/
Although implementing the realtime API in the Opower integration has not yet been completed. That said, I don't think it would be too hard to implement. See: https://github.com/tronikos/opower/issues/24
This realtime data is also available and graphed on your account page on the Con Ed website and mobile app.
I wrote my own code that uses Con Ed's realtime API and writes the data to Prometheus so that I can view it in Grafana. My code was heavily influenced by Home Assistant's Opower integration code. Here's my code: https://github.com/dasl-/pitools/blob/main/sensors/measure_e...
Build glow [1,2]for $10. Hook it up to homeassistant for the price of an old laptop. Measure any and all interesting plugs using an athom [3] smart plug.
As a former electrician turned software engineer and serial entrepreneur I have always been conscious of my utilities consumption. Per Lorde Kelvin one can only improve what one measures and there are many things most people in society complain about yet those individuals could improve if they just measured; the data doesn't lie, people do.
Around about 2006, after being in my newly built home for a few years, I began to ask the questions that many more are just starting to ask now about their utilities. Having had an extensive background in residential and commercial electrical work I knew the options then were limited to measure home consumption digitally but I stumbled upon TED, The Energy Detective. In 2007 I installed TED in my panels and it has been running ever since. I initially only used it as a curiosity item, much akin to many Tesla Solar+PW users today in checking the app for production and consumption data, never before available in such a simple near real-time form of access. TED did however earn it keep in helping me deduce electrical draw issues when systems within the house were changed alongside just other general consumption curiosity.
In 2016 I got serious and started logging all of my utilities at the first of every month directly from my meters and I also cross collected utility bill data into a spreadsheet. That spreadsheet is now large but the information is invaluable in providing me an aggregate collection specifics to me and my family only over that time. Another side story in itself are the errors I have discovered and reported, some of those errors have benefited me greatly, once again you can only know such things through measuring and monitoring. All of this effort was my LONG GAME preparation for going near fossil fuel free and energy independent at my home when I found the correct solution for my needs.
In 2018 we went fully electric with our personal road vehicles. I installed the largest wall charger at the time which supported 220V up to 70A. This of course spiked our home usage at times however free supercharging was a great bonus and still is. Yes, we were early adopters of a fully electric vehicle family now for over 6 years and have driven hundreds of thousands of miles combined across the U.S. and Canada. I am still amazed at how ignorant people are about charging infrastructure since the fossil fuel industry has brainwashed people's expectations with gas stations on every corner. I have referred many an EV owner and while the program no longer exists I still refer people to electric, just referred a CT a few weeks back.
As time passed so too did my roof age and those here aware of asphalt shingle degradation know builder selections rarely last. In 2020 I started down the solar roof planning journey which had me upgrading all aging appliances to EnergyStar and in August of 2021 the solar roof was installed with two PWs. This led me to refactor my spreadsheet to now include my personal generation and consumption which the new system was providing me. Here I mention the TED again because this old still functioning device had provided me with years of historical data and now I would use it to compare the numbers from the new system. Yes, I found discrepancies that no one had found before and those issues had to be resolved within the new system; a new more accurate CT device was required as well as firmware changes. You may be able to hear me still smiling from this near energy independent choice.
My choices have guided my curiosity which has guided my choices and this is still so extremely relevant today in that I have a unique energy loss problem of which I intend to solve through my own energy storage device I am building. Everything provable in life boils down to either science or math so if the science and math check out then it is only the implementation that matters to reach one's goal. I am applying my software, hardware, electronics, and electrical experience as a unique subject matter expert to build something that solves my problem through the dog-food method. Once I have hashed out all the basic issues with this simple "complex system" I am building I will then apply my entrepreneurial talents once again, that whole ‘serial’ thing. You likely know what happens next given the world's growing awareness of a pursuit that I have long had devoted interest in represented by the choices I have made solely from monitoring and measuring. Thanks Kelvin!
So you have to go to a third-party to get your data from a public service. Absurdity is the word that defined our era it seems.
> "Depuis le passage à l'OAuth2.0, il vous faut obligatoirement avoir une entité juridique afin de signer un contrat avec Enedis. Pour avoir une entité juridique, il faut obligatoirement être une société ou une association."
> "Since the transition to OAuth2.0, you must have a legal entity in order to sign a contract with Enedis. To have a legal entity, you must be a company or association"
Yep, that's unfortunately the case for a lot of public entities. Open Banking is similar: at first you may think it means your banking data is open, so you can access it, as a consumer, through an open API... But Open Banking only makes banking data open for licensed data processors under very strict conditions and with quite stringent limitations.
I wonder if a situation similar to Letsencrypt could be setup in the Open Banking space. A non-profit (or something) entity with easy integration for consumers requesting data on their behalf.
My cofounder and I recently went full-time on GridLite, an app and website designed for NYC residents to help manage and split utility bills with roommates. We’ve just added a new feature that gives ConEdison users real-time access to their electricity usage with 15-minute interval data through our app. Perfect for anyone who wants to keep a close eye on their energy consumption. We'd love to hear your feedback from this community!
> the organization managing the national French power grid (Enedis) has been in the process of replacing the legacy “dumb” electricity meters by “smart” meters, known under the brand name “Linky”
My jurisdiction, Ontario Canada, mass implemented these and found that people didn’t really shift their peak demand use much and it’s debatable if the amount spent was worth it. Costs just as much to implement for light users but they’re diminishing returns for any habit changes.
https://www.auditor.on.ca/en/content/annualreports/arreports...
Also went all-in on submetering small units like condominiums+apartments where there’s not much tenant/occupant ability to control their usage/equipment. If anything, just further encourages owners/builders to install the poorest efficiency stuff since they’re not paying the usage bill.
Not surprising that other tactics are more effective (dirt cheap LEDs, renovation programs, improving appliance efficiency… my TV and computers use a fraction of what they used to, wall warts are all SMPS now).
Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
I really wish they could push the telecoms to focus on CPE efficiency since I’m forced to use their equipment.
The real long term idea with smart metering isn't so much demand savings (though I think it was billed as that; and I agree the results are very underwhelming from everything I've seen), it's to start allowing dynamic energy tariffs and getting people incentivized to move load to cheaper times.
We have some of them in the UK and you can see the price differences quite clearly: https://agileprices.co.uk/
I think the idea of having one (or maybe a crude day/night) tariff is really antiquated now when wholesale prices swing so much because of renewables. We are getting to a place where electricity is going to be free/negative a lot of the time and very much more expensive for other time slots.
However, I don't know how much consumers can do about this apart from buying batteries (which is a good thing). I don't think many people will start eating their dinner 3 hours earlier or later or do washing in the middle of the night to save a few dollars here and there. I suppose AC/heating would use enough that it would be worth turning it down at certain times of day.
Really where all the money to be made here is being able to get cheap industrial processes that consumer a load of electricity that can be switched on and off, so only working 25% of the time. This is hard though because there is a lot of capex (and opex) to having equipment and people sitting around doing nothing when the price is too high. But I think the energy savings will be so great there will be something that comes along for this - potentially hydrogen electrolysis.
I got solar last year, so ots been interesting to see how habits change (or dont).
The first stuff was obvious. Our hot water and pool pump were already on timers so those were switched from night to day. Now on sunny days that's a free.
We've moved the dishwasher from night to day. The washing machine was already on day, so no change there.
We gave a small (5kva) battery so a chunk of our evening usage is covered.
There are a few other more subtle habits, harder to spot, and perhaps with more limited gains. Some random oven usage (for not-meal things) is more likely to happen during a sunny day,that sort of thing.
So yes habits have changed, and obviously our grid usage is massively reduced (by about 70%). But equally were not anal about it - things still run when they need to run.
Disclaimer: this is anecdote, not data and ymmv. But saving money is a powerful motivator.
> Some random oven usage (for not-meal things)
Curious: aside from running a cleaning cycle or seasoning a cast iron pan (both of which are at least meal-adjacent), what other non-meal things happen in an oven?
I interpreted "non-meal" as anything except breakfast, dinner, supper. Like a cake
Yeah that was my take on it as well.
Reflowing PCB’s is one thing I can think of.
Drying 3D printer filament too (though I've not tried it myself and not sure I'd want to use my ovens for that).
Drying out 3d printer filament is another.
Also heating up engine casings to get bearings in/out.
"apart from buying batteries" - that is imo precisely enough. We are nearing a time, where a battery that would flatten the avg household demand curve costs under $2000 (without installation costs), and that might be quite enough to change how electrical production works.
Yes, poorly worded from me. I meant more households can't really do a huge amount about load shifting without batteries. Not that batteries are a bad idea or not workable.
If a battery could flatten demand on a household basis, then why not just implement it on a grid basis?
Probably for the same reason many things are the way they are; pushing the cost onto the consumer.
Snark notwithstanding, a thousand batteries distributed close to actual consumers give much more resilience against grid outages, like transmission lines or transformers damaged by a hurricane.
Spreading out the capital costs to those better able to shoulder them.
Nah just tax the rich and make it illegal for corporations based in a tax haven (like Ireland) to do business in our economies.
So rich people? So they can save money while people who can't afford a battery cannot. I guess it's like this for most cost-saving investments, but doing it this way hardly contributes to a more fair society.
>> The real long term idea with smart metering isn't so much demand savings (though I think it was billed as that; and I agree the results are very underwhelming from everything I've seen), it's to start allowing dynamic energy tariffs and getting people incentivized to move load to cheaper times.
The original long/medium/short-term goal of "smart" meters was to eliminate the need to manually check meters and integrate that into the billing systems. It was a direct cost savings to delivery companies. All the fancy variable pricing stuff is an afterthought.
I phrase it as utilities got a gov-mandate to install you new stuff, pass on the cost to you, and save some monthly/bi-monthly opex cost that they can pocket themselves (or at least pat themselves on the back for).
If it costs more than it saves, they don’t mind, actually that’s great (for them).
In rural areas in Ontario, the system used 3G (and for some reason I think only supported 2G in the past) to send readings. So that will be another truck roll (or more likely, cheque to telecoms to keep up some old infra).
I also suspicious of $$$ technical investments to reduce relatively small costs (especially ones where a lot of the dollars leave the area).
It also facilitates half hourly settlement. Previously we used standard profile curves based on the average household to attribute consumption to each 30 minute settlement period, where with smart meters sending half hourly reads you can settle based on the actual consumption.
The transition period includes "elective half hourly settlement" which basically means that as a supplier you can selectively settle meters on a half hourly basis, which created an interesting (but time limited) arbitrage opportunity where you could do some data science to predict which meters would be beneficial to settle half hourly or not
Refs - https://www.ofgem.gov.uk/energy-policy-and-regulation/policy...
- https://www.elexon.co.uk/settlement/profiling/
I’m a bit confused: why do they need visibility into individual household’s load to accomplish this? Can’t you just look at what the whole city is drawing and order based on that?
Or do you mean fully dynamic pricing/billing to end users?
I think this is for situations where customers can choose a 3rd party energy provider. The utility transmits energy to the user and settles with the energy provider.
Makes sense to settle that up near real time, I guess.
This is on the wholesale side - as a supplier your customers consume energy which you're responsible for purchasing, and it's priced in 30 minute chunks. To get visibility into when your specific customers are consuming energy you need smart meter data from the household level
Eating dinner no, but if your washing machine and dishwasher have an internal timer function (most relatively recent models of both appear to), it's pretty easy to load the appliance and tell it to turn on later that night.
> or do washing in the middle of the night
With dynamic tarrifs around here you sometimes make money by doing it during the day, especially on sunny windy days as you get money back for using electricity at that time. My bill is about two thirds of what it would be otherwise (since I cannot install solar panels or batteries it's the only way to have any advantage).
I've automated it so it picks up if the prices goes below a certain set amount, though that's not for everyone.
Btw my parents have been doing off hour washing since the nineties (we've had double meters for a long time). It's nothing new.
The point is that 99% of the contracts have no "dynamic prices", they have few different tariffs established up front an year for the next. In this case you do not need a smart meter to shift load. You simply look at the "current year tariffs" and that's is. If we have dynamic prices than we need a standard data bus for every home appliance connectable to a personal automation or directly to the meter, without that manual load shifting is extremely limited.
In France there is a VERY LIMITED system allow a two wire connection for big appliances were the meter simply tell "cheap or expensive" state and the appliance now that "now the electricity is cheaper, now more expensive". It's way too limited. New homes have since some years a mandatory mitering but without dynamic prices and made to be piloted and throttled loads it's just expensive eye candy stuff.
Personally I have automated via HA as much as I can but such automation is essentially just switches HA can open or close via Shelly integration, there is no real smartness in all appliances even if it's damn cheap adding it from the initial design phase.
My personal experience with "smart" thermostats is that my electric bill went up.
By "smart" I just mean programmable. I had settings for morning, daytime (nobody home), evening, and night. It makes no sense but my total costs went up. This was years ago, so I don't remember exactly what temps I had set for the different times of day. Now I just set the A/C at 76 and leave it there.
Let me paint you a scenario where this is possible: you leave home at 9 AM, and the A/C stops. The house slowly gets hot, maybe 95°F. You plan to arrive at 9 PM, so you program the A/C to get the house to 76°F, which the thing thinks it can do in 1 hour at full blast. But the energy price between 8 PM and 9 PM is the highest of all day: you just programmed the A/C to the worst.
Instead, now you leave it keeping 76°F, and the thing can do it working at 10%. You consume more energy at the end of the day, but the consumption is spreaded through the cheapest hours in the middle of the day, and only a small fraction of it is consumed in the expensive hours from 6 to 10 PM. This is how freezers work, cooling intermitently as the thermostate goes off limits.
I would test if it is worthy money wise, not energy wise, to put the A/C at full blast in the cheapest hours. Say from 4 to 6 PM (the cheapest here in Spain), to get the house as cold as possible, and then try to play with A/C at maybe 5% letting it rise until reaching 76°F at 9 PM.
> I would test if it is worthy money wise, not energy wise, to put the A/C at full blast in the cheapest hours. Say from 4 to 6 PM (the cheapest here in Spain), to get the house as cold as possible, and then try to play with A/C at maybe 5% letting it rise until reaching 76°F at 9 PM.
Depending on how big the house is and how well insulated it is, it very well may make for a big thermal battery and this would work well.
If small and/or poorly insulated or drafty then this will not work well.
Isn't it less expensive and more ecofriendly to turn on the AC when you are actually there? Dumber would be smarter.
Not to mention, you can be late, or early, or not arrive for the whole night.
It might be, you should research how your region produces energy.
For example, where I live the energy produced from 10:00 to 18:00 is almost 100% solar, eolic and nuclear (https://www.esios.ree.es/es/balance?date=04-07-2024&program=... , orange and red bars are solar, light green are wind, dark blue are nuclear). Energy after 19:00 starts to draw gas (yellow bars) to cover the fall in solar production, peaking at 21:00. Incidentally, this also matches prices going from ~5 cents/kWh to ~20 cents/kWh (https://t.me/tarifaluz/3665). So for me it's both ecofriendy and moneyfriendly to shift as much consumption as possible to the 13:00-18:00 hours.
Eco-friendly, possibly, buy cheaper? Maybe not. It depends on when you arrive home. If you arrive home during peak hours when your utility prices are higher, it can be cheaper to run the a/c earlier, while you're not home, to at least get the temperature down into the rough ballpark of where you want it, and then maintain that temperature into the peak hours.
Even the eco-friendly bit isn't always clear, depending on your equipment. It might use less energy overall to maintain your desired temperature 24/7, even when you aren't there. Your particular equipment may run less efficiently if it has to go on full blast for an extended period of time to do a large temperature change when you first get home.
It uses the least energy, but here we are talking about demand shifting to make use of variable electricity sources. It can be worth using more cheap solar energy in the middle of the day instead of less natural gas later on.
Not always because it depends on many factors such as demand energy pricing. The house also has heat inertia, meaning it could take hours to reach a ceratin temperature, so you'd have to turn on the AC hours in advance before you arrive home.
Cool thing is I don’t care about the temperature of the solid mass inside of where I am, just the air really.
I know when I turn on the A/C in my office, it’s not going to cool the concrete wall/floors/ceiling much in the 8h I’m there before I shut it off for the day. And that’s fine.
The solid mass inside the building, the walls and floors heat the air and the AC is working harder to keep up. Also exposed glass to direct sunshine that creates a greenhouse effect.
The key point is that an insulated house acts as a heat/cold storage device, so it's like buying booze and pouring it into a (slightly leaky) bucket during happy hour, to drink later. Even if you loose a bit to the leaks, you're still saving money overall by buying the booze when it's cheap.
An A/C may also operate rather more efficiently when it’s modulated down than when it’s running at full blast.
With heat pumps (like AC) and condensing boilers, it is often more efficient to run for longer and slower as long as that makes your appliance run more efficiently (lower flow temperatures for heating, higher for cooling). Requires the system to support modulation though.
Is there any defined way to do the math on this?
I haven't been able to find even specific case examples showing which consumes less energy: turning down heating/ac when no one's home or just keeping it on constantly.
I'm sure it's pretty complicated because buildings vary, but someone who understands heat transfer should be able to do it at least for a few ideal spherical cows...
> daytime (nobody home)
But that's so last century :) We WFH now.
> It makes no sense but my total costs went up
It does make sense if you were scewing around with the temperature values in excess of 2°C, because the HVAC would work harder to reestablish a new steady state. Most houses have thermal mass and heat inertia and sometimes it takes hours to reach a new temperature set point, the HVAC working at full load to do so. It depends on many factors and it's not easy to optimize without logging the temperatures, the operating cycles of the HVAC and understanding the whole process.
> It makes no sense but my total costs went up.
Due to inflation, the expected state is your costs will go up, even in the case of a small improvement in energy use. A number of western countries also seem to be in a state of energy crisis that could explain the price going up beyond inflation.
So that is less informative than it could be. Did you see your real energy use rise?
> it's to start allowing dynamic energy tariffs and getting people incentivized to move load to cheaper times.
That’s what they rolled out with them, but insufficient change to habits.
> I suppose AC/heating would use enough that it would be worth turning it down at certain times of day.
This is generally the big win, and why they’ve had to still create a program to subsidize smart thermostats and payments to enable the back off features.
Mass installing smart meters to incentivize the public at large to buy+install smarter thermostats is a less effective and more expensive strategy than giving the thermostats away and writing users a guaranteed cheque in exchange for remotely controlling it.
(There are other dynamics at play: electricity here is generally cheap and I pay more in fixed charges than consumption and the heating side is almost universally fossil fuel/wood but that’s achangin)
> That’s what they rolled out with them, but insufficient change to habits.
If that's the case, then that means they didn't set the incentives strongly enough, or didn't educate people well enough about how they can save money. While people do grumble about their electricity bill, they might not realize that there are things they can do to reduce it.
Making up numbers here, but let's say the average/"real" cost of electricity is X. To incentivize different behavior, the utility sets the price for peak hours to X+20%, and drops the price during off-peak hours to X-10%.
They observe behavior for a few months. No meaningful changes in behavior. That just means people value their ability to not think about when they use electricity more than they value the cost savings.
So, set the incentives harder. Set peak hours to X+60%, and off-peak to X-30%. Observe behavior for a few months. Maybe people will start changing their behavior now.
Unless electricity is actually that much more expensive during peak you're falling into the trap of simply artificially making the world worse for the purposes of controlling people's behavior.
People aren't stupid and will immediately recognize when the prices aren't connected to reality and resent you more than change their behavior for you. Most workers don't have access to cheap electricity because they're not home during the daytime hours, and setting up an elaborate series of timers is a non-solution.
You'll never get people to vote for the "everyone's electric bill goes up because fuck you for having a job" bill.
I think electric cars could change this equation. The savings are high enough and the inconvenience low enough.
This is definitely the case - if you have a time-of-use tariff and an EV you charge at home, there's a strong incentive to schedule your charging to the cheapest time of day.
Especially if your EV could be smart enough to do that by itself.
> However, I don't know how much consumers can do about this apart from buying batteries
If one has a water boiler or a heat pump with a buffer, they can run it at full load during cheaper periods. If they have an EV they can also charge that.
The load curve is also changing with renewables.
https://www.enerdynamics.com/Energy-Currents_Blog/The-Electr...
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
https://home.howstuffworks.com/green-living/ice-block-ac.htm
A company called Ice Energy manufactures the Ice Bear, a unit designed to work alongside a traditional air conditioner. Like the large system used by Credit Suisse, the Ice Bear is designed to run indoors and at night, when temperatures and energy costs are lower. Ice Bear creates a block of ice at night that cools the refrigerant during the day, rather than running the refrigerant through a condenser (at peak hours) that requires a lot of energy.
Underneath the Jordan Quad Parking Lot at Stanford University, 360 miles of piping run through a four-million-gallon tank of water. At night, subzero ammonia -- a common refrigerant -- runs through the pipes, freezing the water into giant blocks of ice. The system, which is one of the largest of its kind in the United States, sends cold water from the melting ice throughout Stanford's campus, cooling buildings from noon to 6 p.m. When the facility was first built in the mid-1970s, it skipped the ice stage, instead directly cooling water that was piped through campus. A $22 million renovation -- completed in 1999 -- converted it to its present form, which saves the university a reported $500,000 a year on energy bills.
This is a great post. Thank you to share. How do you know so much about this Stanford University system?
So, it takes at least 44 years to repay? This sounds like a terrible investment. Normally, energy saving projects repay themselves in about 7-10 years. Also, this system sounds incredibly complex. What is the annual maintenance cost? Surely greater than zero.I am aware of using phase change of water for various cooling purposes. Finding references again on them isn't difficult if you know what you're looking for.
Many years ago there was a green building series on KQED that featured such approaches.
Shifting when you are using energy is part of conservation.
As to how it works... it's a cubic rather than planar ice skating rink. You freeze a block of water at night, and then during the day, slowly melt it as you transfer waste heat from the building into it (rather than rejecting the waste heat with a compressor during peak energy use hours).
https://www.energy.gov/eere/buildings/articles/air-condition...
This is a major university, so they could be expected to be a little on the wild side with projects like that. If they're the only one with a system like that, it raises the cost.
Why? I would rather the university conserve spending to reduce cost of tuition. Instead department s of energy, for R and D, or companies flush with cash and wanting to virtue signal can splurge on such projects.
Different budgets can go to different things. Grants for X can't be spent on Y. An endowment may be for a specific goal and likewise can't be spent on some other things.
Stanford is a research institution - and some money that it receives will be going to research rather than trying to reduce enrollment costs.
Alternatively, "hey, they spent $22M on that project... maybe we should shut down the Stanford Liner Accelerator ( https://www-ssrl.slac.stanford.edu/lcls/budget.html ) which had a project cost of $315M."
There are many good institutions of higher learning out there that do not have research as part of their goal. There are 116 different community colleges within California that do not have research as part of their program and the California State University system (as opposed to University of California system) deemphasizes research. Stanford itself is a private school and not part of either of those systems.
On the other hand, people who go to Stanford often want to study under and participate in the research that is being done in a given field - and that implies that research is being done (and money is being spent on it).
As for the School of Sustainability - https://sustainability.stanford.edu/giving/research
> A company called Ice Energy manufactures the Ice Bear, a unit designed to work alongside a traditional air conditioner
Used to manufacture: they declared ch 7 bankruptcy in 2020
More than forty years to amortize the renovation. Ouch.
At any interest rate above 2.2%, they NEVER amortize the renovation!
Only if their energy cost never increases and the figure is resistant to inflation - 500k in 1999 is now equal to $942,584.03. There's also something to be said for the carbon emissions and the fact that we can point to frozen water being a viable system.
They brought ice from the mountains and stored it for the summer in the underground of buildings in areas like Iran thousands of years ago :)
The traditionally hot areas also have other cooling solutions that we forgot about - qanats, wind towers...
Thanks for this, I had never heard of qanats or wind towers.
I'm imagining a giant modern qanat running underneath a city or a large dense neighborhood and each structure reaching down into it to feed a ground-source heatpump in the cooler water like roots. Everything fed by solar panels on the roofs.
This is a close description of the latest urban heating and cooling grids, sometimes called 5th Generation District Heating Networks.
https://5gdhc.eu/5gdhc-in-short/
I bet you could bring a lot of ice from the mountains for $22M.
Isn't this just a terrible investment? $22 million to save $0.5 million per year?
So the payback period is 44 years. The buildings they renovated are quite likely not to exist that long.
Why does it have to be treated as an investment rather than a technology demonstration?
Because that's 22 million which could've bought rather a lot of solar panels and batteries, which would be more then adequate to run the system and much more transferrable in application.
Or you could invest it, make way more then 22 million over that timeframe and do even more.
Cost is a proxy for resource consumption, and in this case it seems like this was incredibly inefficient.
Edit: at current prices you build a 22 MW solar plant instead, for example.
In 1999, those would have been rather different solar panels and batteries ( https://en.wikipedia.org/wiki/Timeline_of_solar_cells#1980–1... ).
The purpose isn't to add to the solar capacity but rather offset the power needed to cool the campus.
https://stanfordmag.org/contents/what-you-don-t-know-about-t...
> By creating ice when electrical rates are low and then “burning” it during the hottest part of the day, the Ice Plant saves Stanford roughly $500,000 per year and decreases Stanford’s peak electrical demand by 8 megawatts.
That's the goal and it is to reduce the impact of https://en.wikipedia.org/wiki/2000–2001_California_electrici...
That's 8 MW ... you say 22 MW today, but in 1999 that 8 MW offset looks more like Solar Two ( https://www.nrel.gov/docs/legosti/fy97/22835.pdf ) which produced 10 MW and cost 58 million on 126 acres of space.
---
And yes, it has changed since then.
https://sesi.stanford.edu/be-empowered/our-story
> In 2015, as part of the Stanford Energy Systems Innovations (SESI) program, a new Central Energy Facility (CEF) was built, and the cogeneration plant and ice plant were retired. SESI transformed the university energy supply from a 100% fossil-fuel-based combined heat and power plant to grid-sourced electricity and a more efficient electric heat recovery system, helping Stanford achieve 100% renewable electricity.
"When the last tree has been cut down, the last fish caught, the last river poisoned, only then will we realize that one cannot eat money"
In Finland people have started since 2022 adapting their electricity use to shift their peak demand. But we started installing smart meters almost 20 years ago. I think the key reason to install them was less about consumer demand response, and more about saving physical visits to read the meters.
It takes some time to adapt (and also some quite extreme price fluctuation to motivate). Also good tools to automate demand response based on market prices were needed. Heat-pumps and EV chargers can now be configured to run on the cheapest hours etc.
One quite unique thing in Finland is our spot electricty price. I think Sweden and Norway also has this?
Basically consumers in these countries have access to the raw eletricity market, and can buy power in one hour increments at the market rate.
This can be very beneficial for the consumer if you can adjust your consumption profile
Yup, and in Norway where 90% of new cars are electric and about 50 % of personal vehicles on the road now are electric, we're charging them a lot. Which most people now schedule to happen at nighttime to save money.
Yep, I have this with Tibber[1] in Sweden. We haven’t hugely changed how we consume electricity for small stuff, but for bigger things like car charging or even things like pyrolytic cleaning of the oven it’s easy to pick times when the prices are low, especially at the moment when electricity often goes down to near-zero or even negative.
[1] https://tibber.com/en
Also available in Australia, https://www.amber.com.au
>> saving physical visits to read the meters
Why can't users read the meters themselves and send to the electric company once a month?
That was often a thing. You’d get estimated bills based on your history, but could phone in/mail in your reading if you wanted a bill correction.
What do you mean "was"? Every electricity provider in my country has a web interface where you can send your reading in monthly.
They send someone to physically read the meter every 3-6 months so you can't cheat, but other than that they will bill you what you declared if you send it in.
Readings are send remotely and automatically to connection provider. They pass data to seller of electricity. This data can be viewed nearly live or at most in few days online. It is all automated now. No need for anyone to go and read the meter anymore. Or even estimate consumption.
There are some special case like building where I live. Where I pay to the building, with very reasonable rate as there is no extra standing charges...
They haven't reached full automation here.
What I wonder is, who can read this consumption data besides the "connection provider"? How easy is it to drive around with a laptop and see who hasn't been home the past few days?
https://www.fingrid.fi/en/electricity-market/datahub/questio...
So basically it is uploaded to cloud and some people will obviously have access to data. Like customer support.
I think technically it is possible to listen to air interface, but either it is some mobile or some power line communication so cracking that is complex enough.
Why hand wash dishes when we have dishwasters?
I was asking about the arrangement of sending a worker monthly vs reading the meter yourself, not automated vs non automated.
Smart meter means you do not have to do either. Meter itself can send the readings nearly live over power network or mobile connection. Thus no human needs to read the meter anymore. Saves time and trouble on all sides.
They no longer send workers monthly. Quarterly at best. Add the complications with the access into each type of building to read the meters. Also pay the worker, pay for their heathcare, when the meters can send live updates over NB IoT.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
It makes sense if you think of the thermal mass as a battery. Technology connections says he does that with his air conditioner, runs it hard overnight so it stays cold longer with less effort during the day
It being cold also tends to help with better sleep.
We set our AC to 76 during most of the day, 80 during on-peak pricing, and 72 overnight.
https://fridge0.branchable.com/thermal_mass/
> runs it hard overnight so it stays cold longer with less effort during the day
Shouldn't it be the other way around? The days when electricity was cheaper at night are long gone.
> Shouldn't it be the other way around? The days when electricity was cheaper at night are long gone.
Are they? Here in California most energy companies offer plans with much cheaper rates overnight for EV charging (i.e. $0.15 vs $0.45-$0.90 peak during the day).
Commercial and industrial customers account for two thirds of power consumption so there's a lot of surplus generation at night. Lots of industrial users have agreements where the power company can signal them to soak up surplus power but that's also less effective at night when wind picks up.
It’s still the case in Canada because our peak electricity usage is driven by summer daytime aircon and solar is a small percentage of generation.
Heating is still primarily fossil fuel, for now.
Night time loads are generally low with big baseload hydro and nuclear generation in the more populated states/provinces.
> The days when electricity was cheaper at night are long gone.
That must be a regional thing. In the PNW, my power rate during most of the day is twice what it is at night, and during the evening peak it doubles again.
Also in PNW, and the price for my electricity does not change during a day.
In what markets? In most/all of the markets I can think of, night time rates are still cheaper. Even in markets with large Solar installations (CA, USA) peak rates are still during the day.
take a look at southern california edison's time of use rates. Summer day and night are the same price, but afternoon/evening 4-9pm are more expensive or you can opt for 5-8pm way more expensive.
In the Winter though, energy is cheaper starting at 8am, when the sun is out. Still more expensive from 4-9/5-8
https://www.sce.com/residential/rates/Time-Of-Use-Residentia...
Heat pumps are more efficient the smaller the temperature gradient is.
Heat pumps use less energy when there's a small temperature gradient (assuming a good turndown ratio, cheap ones aren't so good), but they're more efficient when there's a large gradient. That's why they require careful modeling before being used for hydronic heating.
Heat pumps are improving to work in wider temperature ranges.
2-4pm for me is about 6x the price of 2-4am. NYC.
Smart meters achieve lots of goals. The most marketable was time-of-use electricity pricing.
My distribution company in Ontario makes it very clear when those times are and what the electricity prices are. On-peak is approx CAD 0.18 / kwh and off-peak is CAD 0.11 /kWh. That's over 50% difference.
The problem in Ontario, QC, MB and BC is that electricity is cheap, relative to our standard of living. The incentive to be more efficient is weak because the savings are not worth the effort.
The other reasons smart meters were installed is to speed up the meter reading process and to gather data on when exactly people are using electricity.
The electricity distribution system is passive and the grid operator has little to no visibility on what is happening at various places and times. Smart meters are the foundational tech to enable a bunch of other initiatives and planning.
Hydro-Québec, for example, allow you to see your live power draw. My meter (2011 model) can do this but my electricity distributor will not share the decryption key.
Those meters may not do much to change electricity consumption habits but they are far from a loss. The investment is absolutely worth it.
Wdym, electricity distributor? I thought hydro Québec handles 100% of the distribution too. Is this something new?
Hydro-Québec is vertically integrated.
I'm in Ontario where the situation is different. We have a quasi-deregulated market with local electricity distribution companies aka LDCs.
Ahh makes sense! Is HQ a player in the Ontario market? A part from electricity export that is.
Just buy a bit bigger one, and fill the unused space with water. Every open now exchanges less air and you can turn it off for hours or a day without any impact of the temperature inside - water is good capacitor of temperature.
We fill it up with food that otherwise doesn't need to be refrigerated but they keep better at low temperatures, like fruit jams, unopened cans or olive oil. One could fill it with kimchi, beer or bottled water though.
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Changing the temperature of a fridge based on electricity rates just feels like a bad idea. A lot of food can have its texture ruined by slow freezing (a common occurrence at the back of many fridges already) and waiting to get food down to the target temperature will just lead to bacterial growth.
Seems like having an ultra-chill button for that function would help with that.
Might want some phase-change materials to optimize the thermal banking.
That’s easier for a freezer (very salty water bottles) than a fridge (need some carefully produced waxes), but fridge contents should be more tolerant of temperature variability.
Would add that refrigeration is more efficient at night when ambient temperatures are generally cooler and/or heating needs are greater, so the “ultra-chill overnight and daytime backoff” might not increase consumption.
the fast chill button is a thing. it's in both my 8yr old GE and my newer samsung..I never use it though but it's made for putting still warm leftovers in and getting them cold fast
Need a thing to press that button 1/2 hour before peak rates take effect.
But I wonder if it just circulates more air and the thermostat doesn’t adjust its set points.
These functions do not change fridge temperature, choose when to run the defrost functions for no-frost units (a quick wall heating to melt the ice and quickly came back to normal), choose to run or not some ancillary functions (like making ice cubes) etc. They are VERY chatty https://news.ycombinator.com/item?id=38984609 but not much useful.
Shifting loads for hot water, if you have big enough reservoirs on contrary change MUCH the game, being able to shift some loads automatically, like leaving a dishwasher or a washing machines, a pumped irrigation systems and so on might significantly change the overall bill to makes investments in that sense meaningful.
This is the entire concept behind harvest.
https://www.harvest-thermal.com/product
A recent podcast turned me onto them. The idea is to heat water to higher temps than normal and use that extra heat as an energy store for use during peak times.
I think is not a novel idea: there are various vendors here in EU that offer "thermodynamic VMCs", meaning dual-flux ventilation system [1] with a small heat-pump between the to air flows, sucking heat from the outgoing air, heating the incoming flow in winter, in summer to avoid injecting too humid water they passively exchange outgoing fresh air with the incoming and the heat a water tank for sanitary water, cooling as needed the incoming air after the passive exchange, for instance https://www.broferpura.it/en/products/Domestic/compact06.htm... this reduce the number of compressors a home need in mild climate and new homes.
For me I simply run the main heat pump at full power during the day on p.v. reducing the grid absorption for some hours in winter and for sanitary water almost zeroing it since 300l @60-65℃ (140-149℉) suffice for a whole day, at least when I have enough p.v. a day after another.
Honestly I doubt it's possible to store enough heat with current tech to compensate the home heating needs, it's possible for sanitary hot water (except for a swimming pool) but no more. However for mild climate for some months might be enough to significantly reduce the grid absorption. The sole issue here is that heat pumps now, without any specific reasons, have skyrocketed in retail price enough to make them far less convenient than just few years ago... So the economy is still not much.
[1] an image should be sufficient, I do not know their common name in English, sorry https://lacentrale-eco.com/images/blog/fonctionnement-vmc-do...
This is very standard stuff in Finland for decades. And before heat pumps became popular large tanks were common and those were heated during the night.
Most freezers already do a defrost cycle so could probably play with that. It’s only a few degrees oscillation so idk how much savings you could get there.
A modern fridge only consumes around 350kW a year or so, so any savings are going to be modest. It would not be the first target if I wanted to cut my power usage, especially if the consequence was going to be more freezer burn.
I think the consequence would be less freezer burn and more frost buildup.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
I don't believe there would be many if any cost savings from doing this. The engineering thought behind it would cost more than the actual savings. It would make a lot more sense to buy a chest fridge which I imagine uses half or less the energy of a typical standing fridge.
The only estimates I've seen say 10-25 percent more efficient.
Department of Energy / EnergyStar state 50% energy savings for freezers. Freezer/fridge might not translate perfectly but I imagine a fridge is getting opened more often during the day which would skew that even more towards the chest being more efficient.
Not sure how you come to 10%
Wow. That is a surprising number: "An ENERGY STAR certified chest freezer uses about 215 kWh of electricity and costs about $30 per year to run, while an ENERGY STAR certified upright freezer uses about 395 kWh of electricity and costs about $60 per year to run."
https://www.energystar.gov/products/freezers
When you open the chest freezer, you don't have cold air "spilling" out of it. It remains in the chest.
On the other hand, when you open a freezer that has a door on the front, a substantial portion of the cold air spills out of it.
When freezers are coupled with refrigerators, the way that many of them work is by having the freezer air descend into the refrigerator through baffles (which again, makes the freezer work to cool the air that was exchanged with the refrigerator).
Most of the cold is in the solids and liquids though.
That wonderful feeling of the cool gas leaking out leads people to overestimate how much cold falls out.
Some more modern fridges/freezers halt the compressor/blower when the door is open which probably accomplishes more savings.
I presume that turning over the air probably causes more icing in the freezer.
Does a chest freezer have less of a problem with icing? And are they easier to deice?
Modern freezers have automatic defrosting systems so maybe moot...
It is kind of neat to watch the frost ring descend from the top of the chest freezer lower and lower along the walls.
It is pretty easy to scrape off, too.
If it's a freezer you use often, it's worth considering upright, because you want to be able to see, access and use most of the freezer, instead of just the top.
Add to it small humans who may do the same and the $30/year in electricity differences can be dwarfed by the benefits of having a freezer contain meal prep, etc.
Combining a small standup freezer with something like a Foodsaver is an easy win to reduce waste / thrown away groceries, as well as helping with off-season wishes.
Buying less from the inflation fuelling large grocery stores is something that is well within reach.
So save $30/year increase the price of repairs and the chance of it breaking.
How does a chest freezer/fridge have increased chances of repairs?
I mean it must have a downside because otherwise I’ll have to admit I’ve made a mistake by not having one already.
Chest freezers are less convenient to access, and require different accommodation than an upright refrigerator.
In a chest freezer:
- You access everything from the top. This would require something like a section of cabinetry which opens to the top, or a chest freezer occupying kitchen or other living space. Since the freezer is low and wide, this has a larger floor footprint than an upright fridge.
- Contents are stacked vertically, which means you have to dig through the pile to get to items on the bottom. There might be designs which make this easier (e.g., fold-up shelving), but that would have to accommodate another aspect which is that ...
- Chest freezers tend to frost over fairly heavily. Cold air doesn't spill out, but warm air tends to settle down into the fridge, and as it chills, loses its humidity as frost. Many or most chest freezers don't have an automatic defrost cycle,[1] and frost will build up on inside walls, contents, and any moving parts such as the fold-up shelving I'd described. Defrosting is typically done manually with chest freezers.
- Chest freezers are, well, freezers. I suspect some might be able to operate as refrigerators, but AFAIU they tend to cool somewhat unevenly as refrigerators rely on active air circulation to cool contents and avoid hot or cold spots.
If you're aware of these limitations and/or can work around them, e.g., by having a trundle-shelf or top-access countertop to address floorspace / footprint issues, and can find a way to easily access contents, chest-type designs can be a good choice.
________________________________
Notes:
1. Refrigerator defrost cycles involve halting the cooling cycle and activating heating elements in the refrigerator (and freezer-space) walls to melt any accumulated frost. This itself is both a considerable energy expenditure, and tends to accelerate freezer burn and other ageing of food often giving unpleasant taste or texture.
The downside is it’s a chest and does not fit any kitchen floor plan. You would need to purposefully put it in your plans.
We have two chest freezers and an upright freezer. The chest freezers outlast the upright freezer, and there's no shelves* to get in the way of optimal packing.
*However, you have to unpack when you want something from the bottom. This is why we have an upright freezer. We store cheese curds from our dairy in it, and we want to access them quickly and easily and regularly. Also we use ice packs for shipping, and the shelves make it easy to freeze ice packs flat.
Having a smaller upright freezer for items that will be used in the near future is helpful. Leaves room to buy a larger chest freezer later on.
It's far more annoying to fetch something from the bottom of a chest freezer than it is to fetch it from the back of an upright freezer.
And it can easily become essentially a black hole. Not that that doesn’t happen with my upright too. I’m split on whether I shouldn’t just have bought a chest freezer when I bought my spare freezer.
I'm in BC, with BC Hydro. The smart meter means that everyone can see their own daily usage and trends. I'm sure most won't look, though I do. What I found more useful is the paired device from Rainforest Automation, e.g. https://www.rainforestautomation.com/rfa-z114-eagle-200-2/.
I had to buy this, but it's paired to my specific meter. Basically it gives me a means to see my overall usage in real time, so that I know how whatever we are doing, affects the usage.
BC Hydro has had programs such as a voluntary one, where you get an email about a 3-hour period the next day. They'd like you to drop your usage for that period by 20%, and you get a few dollars per successful drop at the end of the season. With our heat pump for heat, we just switch it off for that time, and skip using the clothes dryer then. At the end of the season, we got maybe $50 off our bill in credits.
They have proposed a time-based plan, with discounts for night-time. I have not elected to try that out, because it also came with penalties for daytime usage.
I'm in Ontario. 90% of my electricity usage consists of charging my electric car. The ultra-low overnight rate of 2.8 cents per kWh, introduced during the past year, is a big win for EV owners. This rate is seven times cheaper than the cheapest rate mentioned in the article, and ten times cheaper than the peak rate in Ontario. It is very, very easy to schedule your car to charge during overnight hours if you have a home with a garage. You better believe that smart pricing has shifted when I charge my car! I think this kind of benefit will become more pronounced as more people shift to electric vehicles. People won't shift demand for small appliances, but when 90% of your usage is made up of one single thing that is easy to shift, you'll get some returns.
there are some big assumptions here.
that you own a garage, that your electric bill is in your name, that your driving distance makes this worth it, that your other electric consumption is small and so on. It works for you, that's great but something you didn't mention is the higher on-peak rate.
If you have electric heating or need to charge your EV during the day, the increased rate there can easily offset your overnight rate savings.
These assumptions are not at all unreasonable. We are not talking about a tiny minority. More than half of Americans have a garage. Utilities aren't concerned about individual households; they're concerned about average behavior. I'm just guessing here, but my guess is that if even (say) 20% of households do what I do, that alone probably makes it worth it.
I drive about 15000 km per year, almost exactly the Canadian average. There are a lot of potential households fitting this profile.
(If you're needing to charge your EV during the day, then the higher daytime home electricity rate is irrelevant. My EV has a 300 mile range, which is typical. I cannot think of any scenario where I simultaneously 1) drive 300 miles in a single day, and 2) somehow also remain close enough to home to charge at home, so that the daytime home electricity rate matters, and 3) can't wait until the night to charge.)
Interesting. I sense night time use could extend well to charging an array of batteries until Solar is fully up and provide some options.
There aren’t a ton of smart appliances because there aren’t a ton of smart grids. We need smart grids with, like, really significant demand based pricing before people are going to care about smart appliances. And of course there’s no reason to get smart appliances if you don’t have that kind of grid.
Somebody has to go first. In the bright side it really is unambiguous whose job it is. Utility providers are often government subsidized or at least heavily regulated government-provided monopolies. They have the responsibility to act in the public good, and provide strong enough incentives to get people to come along with them.
We’re close to this. California, which is not the world but is a major market, has pretty transparent grids with variable pricing. I don’t know if they’re “first” but they’re a big enough market to drive change.
Electric Cars use a ton of electricity and have these sorts of features for a while now. Apple even built grid pricing info into their latest “Home” app for California users.
I think there aren’t smart appliances because there is no demand for people to change their behavior. No one is going to put off cooking dinner for cheaper oven use. We see it with cars and smart thermostats because it’s largely set-and-forget with people.
We should slowly expand what “set and forget” means. Dishwashers and clothing washers for example, we could modify our behavior a little bit without any major inconvenience (load it up, put in the soap, and then let it schedule itself, you’ll get a notification when it runs).
Ovens and stoves are, I think, an unusually bad case. Although, slow cooking should be shiftable, right? Maybe we’ll have to eat slow cooked ribs instead of hamburgers. You know, to save the planet or whatever.
Instant pots, kettles, dishwashers, microwaves and toasters all reduce energy consumption to do the same thing, but I don’t think anyone bought them for those reasons.
The most effective method to reduce/shift consumption is just to make it the easier way.
Adding cognitive load to shopping decisions and their daily lives is predictably ineffective for the general public (and almost universally hated).
That majority will be a bit poorer because of it, and many will cheer that aspect but it also means the target goal has failed.
Or cooking with gas instead?
Gas has its own set of issues, from terrible leakage in every stage of distribution, to microparticules during cooking (which directly affects the health everyone that lives in the household), going through the ecological impact of production, and without forgetting the really bad failure mode they have when buildings fail in areas prone to earthquakes.
Methane is a potent greenhouse gas, and cooking with gas is far worse than a renewables-powered electric stove.
The savings made on meter readings, the reduction in meter breakdowns, the detection of illegal connections and other factors alone justify the renewal of electricity meters.
The linky meter can also be remotely controlled to reduce the maximum power delivery for bad debtors (it's very rare in France for electricity to be completely cut off).
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
If you are a bit technical, you could convert your fridge into a smart fridge that does exactly that.
Throw a temp sensor into the fridge, set the fridge temp to as cold as it will go, then plug your fridge into a smart plug. From there, you can monitor the interior temp and turn on the fridge based on when you want to super chill. Dead simple to do something like this with home assistant.
Don't blame it on the smart meters, blame it on the governments that refuse to structure the plans to take advantage of it. I figured it would be a no brainer to switch to the time of use plan because we have an electric car we charge at night, but no, the standard non time of use plan is cheaper for us.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
Maybe just use a freezer and put it on an old school outlet timer? Run it at night and treat it like an ice box during the day.
I think it would be too well insulated to function very well in a fully automated way; you'd have to manually open the door every morning.
> found that people didn’t really shift their peak demand use much and it’s debatable if the amount spent was worth it.
This depends on whether the goal was to reduce the amount of peak usage, or increase the amount of revenue that comes from peak usage.
Putting smart meters in probably paid for itself via higher income.
My house moved to smart meters over a year ago. Still get the one total usage amount per month. Even if I log in online there is no way to see what I use even per day.
I do think we need to have a price that changes during the day but I suspect most people wont tolerate it and the politicians wont allow it.
In Denmark, I can see my hour-by-hour usage if I log in online.
There's also a chart showing the prices: https://andelenergi.dk/el/timepris/
and apps and so on.
Yeah my Dad has this too. I expected similar. Lots of rules in the USA makes it difficult to do anything different.
My fridge (some LG models supposedly does this. I say “supposedly” because this requires connecting to Wi-Fi, which I don’t want to do, but in their the energy company sends it signals about how the grid is doing and the fridge goes into energy saver when appropriate.
A nice little vlan with only internet access would let you connect your fridge to your WiFi without worry. Most WiFi + router combos come with a Guest vlan which already does this out of the box.
hesitant to wifi connect my fridge too but my elec provider offers a decent discount for setting it up.
Links? Didn’t think that was a thing for fridges, just hvac/water heaters.
ahh you are correct, I was conflating 2 things..however it's called a smart grid fridge and it pulls dynamic pricing from the elec provider and does the optimization on its own
> wall warts are all SMPS now
TIL about switched-mode power supplies... https://en.wikipedia.org/wiki/Switched-mode_power_supply
In my mind, the smart grid would be most useful for distributed storage. Like if your car charger has a battery pack in it to quick charge your car. Or just a battery that could charge on off-hours to lessen peak load.
>Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high. Kinda antithetical to use more electricity to save but it’s true.
you put a backup battery system in between your house and the power grid, switch power hungry appliances to battery during peak times.
over a long enough period this should achieve what you're looking for and is the most likely solution to "force" people off the grid at peak times.
it's just that right now where like you said - why bother when all you're saving is a couple hundred bucks? spending that mental energy on things that will earn you money is better.
I have a GE fridge and I have a time of use plan. Except the times are wrong. And I cannot adjust them through their app.
> Still can’t find a “smart fridge” that runs in ultra-chill mode when rates are cheap and backs off when they’re high.
Yeah... That requires a standard way to communicate the energy price to the fridge. You won't get that with municipal regulation.
And without devices auto-adjusting their behavior, you won't get a lot of savings.
Your fridge doesn't need to know energy prices. Fridges are for cooling, not computing your bills, and giving them access to too much data only encourages the usual IoT vendor abuse patterns. It should be enough for it to get a proxy signal. "Cheap tariff" / "expensive tariff". Or maybe continuous 0-1 control signal. Optimizing energy use for household or building already requires an external decision-making center anyway.
But it does need a warning. If the two wire suddenly tells it "expensive tariff," that's too late to cool down a little.
It could just be telling it what your time-of-use rates and hours are. I think most places with variable rates at this point are on a schedule that does not often change, only a few places have completely dynamic pricing that would need real time information from the grid operator.
Generally Time of Day electricity billing is just an average costing at fixed windows of time. 2-way (or really, just 1-way is actually necessary) comms not required.
Not too common to have totally dynamic pricing. And even if you did, they have general trends.
I did a project with a french Linky a few years ago that used an ESP8266 to grab the serial data stream from that exposed port on the bottom and log the interesting line items it prints out to a InfluxDB timeseries database running on a local server and use Grafana to get a dashboard of various metrics.
I remember having to do some sleuthing with the serial port as it wasn't something standard - it was like 7 bits, no parity, 1 stop bit, or something like that. And a small circuit to do level shifting for the ESP8266.
The result was data on wattage draw approx every 1 second. This allowed for some very, very fine analysis in the data.
I tell people about this when I talk about various sidechannel attacks on things that use data like this- for instance, after observing the data for a while, I could tell which floor of the house someone was on by watching transients of the wattage and the quantized changes of various devices turned on and off - e.g. the kitchen has a kettle that uses 1220 +/- 5 watts, every time, and nothing else in the house results in a step change of that value. The top floor bedroom has lights that use exactly 42 watts. The laundry machine starts up with a very specific ramp and then oscillates between two levels of power with a period of 30 seconds, etc.
You can figure a lot out about the movements of people and what they are doing by simply having fine enough time resolution on a single number - the total power consumption of the entire house.
Indeed, and to be fair most people I know who were reticent to the new Linky were not "fearing that the new meters would fry their brain using Bill Gates’ evil 5G Wi-Fi waves", but were concerned about their privacy.
Many are looking for excuses to continue using a modified meter and continue to defraud.
This is more difficult with a linky (but not impossible, by installing a bypass).
Now add in the fine grain resolution of water consumption and internet, and you will know more about them that themselves.
In Finland (and I guess at least other Nordics as well) we are starting to get neters with so called P1-port, which is open for the user to get their data. All I needed was a wire with RJ26 and an ESP8622 with some esphome definitions and now I get all kinds of data from the meter every 4 seconds. Total consumption, consumption, amperage and voltages per phase etc.
In Germany we have an infrared one-way connection (SML protocol). I hooked a Raspberry Pi Zero WH (consumes only 0.7 Watt) with Ethernet Hat and USB-Infrared-Reader-Cable to the Smart Meter. The PI reads and transmits all readings over MQTT to my InfluxDB 2.0, which is running virtualized on Proxmox. At the same time, I also read my solar inverter through Modbus TCP (via OSS called "Solaranzeige"), to the same Influx DB. Both is visualized in Grafana. It is a nice stack that did not produce any problems in 7+ years.
All of this helped me to better understand my electricity consumption.
This is a great post! Did you blog about it? I am sure HN would love a post like that. I would generate lots of interesting convos around similar setups in different countries.
Ah, you mention a pain point. It's on my list for years now.. I've just added 60 kWp Solar plant [1] to my existing 30 kWp; once this is through, my monitoring stack will need updating and I will blog about it here [2].
[1]: https://himself.alexanderdunkel.com/@alex/112443427011946461
[2]: https://du.nkel.dev/
The port/protocol originates in Netherlands and is getting widely implemented across the EU. It is really nice that the port provides power (esp. in recent versions) for an ESP, so you don't need to worry about bringing power to where your meter is (which may be outdoors.)
Yeah, P1 has been around for a decade or so in the Netherlands. If don’t feel like setting up an MCU yourself, Homewizard Energy is pretty good. I don’t use their services, but you can enable a simple API on the local network that gives you a JSON representation of the ‘telegrams’ that come out of the P1 serial port.
https://www.homewizard.com/p1-meter/
Oh yes, now I remember reading the P1 spec and it does indeed say that it has been in use in the Netherlands for many years already. In Finland we also call it the HAN-port or the H1-port. Also, I must clarify that it uses RJ12, not RJ26 which I don’t even think exists.
The HomeWizard stuff is great. They also make a water meter, separate kWh meters in 1 or 3 phase and smart plugs.
If you have a subscription to their service, they can be programmed to eg turn on when there's excess solar power etc. And integrates with HomeAssistant.
Our EL provider in SE Finland is installing (without charge) a new P1 meter next spring. It will be bidirectional, i.e. ready for solar-to-grid.
This is far from any metro area, so it might be a countrywide rollout.
I thought the old meters were all bidirectional (ie: the spinning wheel could go backwards if you back-fed). Dunno what older gen “smart”meters would do. But I guess the newer meters are capable of paying you some reduced/enhanced rate for backfeeding?
> installing (without charge)
Who’s paying for it?
Some combo of the ratepayer base and the taxpayer base, I assume.
Germany here, I have an optical UART, I get the data every second.
I have my dumb electricity meter sending my electric usage to google sheets every one minute
I used an ESP32 with a very basic light sensor, the sensor was blue tacked over the 1000th/Kwatt LED (this blinks 1000 times per unit of electricity used) the info is sent it over my wifi to google sheets
it also records the sum per hour indefinately, or until google sheets complains
Is this a common feature of dumb power meters? I’ve wanted to get data out of my dumb meter for a while now so I’m interested to learn more
I'm unsure, I moved in to the house recently and noticed the flashing LED on the 'dumb' electricity meter and thought, umm that could be useful.
I've not researched if any other meter has this function
The UK has smart energy meters for a lot of customers. Octopus are an energy supplier which is using them to great effect for data nerds and people who want to save money.
To get the data out, you can just call their API to get daily consuption figures, split into half hourly blocks[0]. They also allow you to just download a CVS file directly from the energy use section of their website.
The data in the API is only update daily, but they can give you a tiny addon device[1] for free which will allow you to access live usage in realtime (updates ever 10 seconds I think).
I use a Home Assistant integration to collect all this data live there.
To make use of the smart meter, they also have a series of tarrifs which change price dynamically. The simplist is Tracker[2] which charges you a different price per unit every day based on the wholesale price. There's also Agile[3] which is the same concept but the price changes every 30 minutes with higher highs and lower lows. That one is great if you can shift your energy usage outside of peak times.
They also have "intelligent" tarrifs where you allow them to control your car charger[4] or home battery[5] so it charges when it's cheapest.
Octopus are doing really great things in the UK and part of their business is that they sell the backend as a service to other energy companies who were previously stuck in the stone age as Kraken[6].
[0] https://developer.octopus.energy/docs/api/
[1] https://octopus.energy/blog/octopus-home-mini/
[2] https://octopus.energy/smart/tracker/
[3] https://octopus.energy/smart/agile/
[4] https://octopus.energy/smart/intelligent-octopus-go/
[5] https://octopus.energy/smart/intelligent-octopus-flux/
[6] https://kraken.tech
Octopus is currently trying to set up in France. They've got a pretty amazing advertising campaign where you don't know what they're selling except for a pink mascot.
Alternative suppliers to EDF have a very bad reputation in France. Their contracts are often unclear and subject to major price variations (+100% after the start of the war in Ukraine). Some use unscrupulous prospectors who take advantage of elderly people to get them to change their contract (Total Energy, I'm thinking of you).
The majority just buy Mw/h from EDF to resell and speculate on future production contracts. They don't invest a single euro in production facilities.
The founder of Octopus was from a software background and has claimed that Octopus (the energy company) was initially just to demo the potential of the software.
Ironic that their software is so terrible then - it took over two years for their support to do 'something' to my account so I could actually pay my bills.
Their hiring is awful too, they took 2 months to get back to me with feedback on my takehome task. I'd already been in a new job for three weeks when they finally came back.
I would love a way to turn off my electric hot water heater between the hours of about 10pm and 7am.
I see no reason to keep the water hot during the time absolutely nobody needs it, and we know it will take less energy to heat it back up again rather than keep it at temperature.
Also, yes, I have turned the temperature down as low as it will go.
I had my electrician build me such a box, though the result was so simple that if you are handy I'm sure you could do it yourself.
The contents of the box are
1. A programable timer light switch: https://leviton.com/products/vpt24-1pz
2. A 120 volt controlled contactor. I'm not entirely sure which one it is, but I think it is https://ca.rs-online.com/product/eaton-cutler-hammer/c25bnb2...
The box has a 240 volt circuit and a 120 volt circuit into it. The 120 volt circuit is connected to the programable timer light switch, which is then connected to the control inputs of the contactor.
The 240 volt line connects to the contactor and then on the other side of the contactor it connects goes out of the box and to the water heater.
For me I've programmed my hot water heater to turn off from 4pm to 11pm on weekdays, which avoids heating the water during peak time of day rates at my location. (I typically shower sometime during that period.)
I can open the box and press the switch on the timer if I ever want to temporarily override the program.
That all said, I don't have any measurements to tell me if it is worth the expense. Although it is quite clear from my hourly power usage when the hot water tank switches on at 11 pm.
Awesome, thanks very much.
I wonder if it would be worth keeping it off until sometime in the am the following day - do you need piping hot water from 11pm until about 5am?
On weekdays, my price of electricity from 11pm to 7am is about 4 times cheaper than from 7am to 4pm, and about 10 times cheaper than from 4pm to 9pm.
Also I usually run the dishwasher and laundry sometime after 11pm, so it is usually helpful to have hot water available overnight.
Edit: I should mention that I have a ventless combo washer/dryer, so my clothes come out clean and dry in the morning. Unfortunately they are not folded.
Are you sure this is true? The thermal mass of water is a lot, and in theory your tank should be well insulated?
It's always true, for any tank on any environment.
Are you saying insulation is worthless?
To understand how this works it's important to know that temperature loss is linearly proportional to the temperature difference. Insulation reduces the ratio independently of temperature.
As an approximate example, suppose if takes one hour for the tank/building to reduce to a thermostat set-point 10% lower than the 'high' set point. Further assume you could use that lower set point for 11 hours, so the tank/building temperature is 10% lower for a full 10 hours. Finally, assume increasing the temperature of the tank/building by 10% takes one unit of energy.
In order to maintain the low set point, the first hour is free since we are losing temperature. The middle 9 hours need (190%) = 0.9 units per hour for a total of 8.1 units. In the 10th hour the low-set point scenario needs to warm up to the high set point and overcome heat loss so that individual hour requires more energy than the high set-point scenario: (1110%) = 1.1 units for that single hour to return to the high set point.
In total the low-set point needs 0 + 8.1 + 1.1 = 9.2 units of energy over the 11 hours.
For the full 11 hours the energy required to maintain the high set point is 11 units (1 unit per hour to make up for 10% loss).
Insulation is worthwhile, but has nothing to do with what you are asking.
If you are heating a house, or a water tank, or anything, it requires much more energy to keep it at a constant temp 24x7 than it does to let it cool down when you don't need it hot, and then just heat it back up again later.
That is why "smart" thermostats like the Nest became so popular. No need to heat your house while you are away during the day. So let it cool down a bit, then just warm it back up again soon before you come home. Much less energy used.
That fully depends on the level of insulation. Newly build houses here in The Netherlands rarely cool down when heating is off, and the temperature stays generally stable, even when you are out (and the heating is off).
My Quooker is so well insulated, that you should only turn it off if you aren’t home for a week. Otherwise is exactly counter to what you say: more energy efficient to keep it at temperature instead of letting it cool and heating it again [0].
[0] https://hotwatertaps.com/turning-off-boiling-water-tap/
No, that is still not true, no matter how good the insulation.
> That fully depends on the level of insulation. Newly build houses here in The Netherlands rarely cool down when heating is off, and the temperature stays generally stable, even when you are out (and the heating is off).
Even if it's a few days, and it does drop a few degrees, you still spend less energy bringing it back up to whatever temperature than you would have to keep it there the entire time.
Do you have anything to support that claim? Because in my belief this follows normal thermodynamics, which means that if the energy dissipation over an amount of time is less than the energy cost to heat, it makes sense to do it.
Do you think there is no relation between the thickness of the insulation and the time it takes before reheating is more energy efficient?
If you’ve got a 240v water heater that is on a 40A or smaller breaker, this would work: https://www.intermatic.com/Catalog/us/Products/Timer-Control...
If it’s larger than 40A @ 240V, you could buy a 120v astronomical time clock switch and use the output of that as the input to a 120v control coil for a contactor sized for your water heater.
Per @quickthrowman recommendation I can add that this is the way to go for an electric hot water heater having installed many of these Intermatic time clocks. The old ones were analog and one can hear a clicking but they do make them digital now, YMMV.
There are timer devices for this.
Generally you want your water heater to keep the water hot enough to kill any bacteria and prevent their growth.
Water heaters in Britain since around the 1980s would have a basic timer switch to turn them off/on up to twice a day.
The old (pre-electronics) ones are easy to understand — the heating/water comes on (in this case) at 10:00 and goes off at 16:30, then goes on again at 21:00 and off at 07:00: https://www.alamy.com/stock-photo-timer-control-for-hot-wate...
I use a $8 programmable plug timer switch off Aliexpress to do exactly that. But it's only useful when I live alone. When a girlfriend is living in, messing with hot water supply is an absolute no-no!
Do you have a link please? I've only seen the ones that plugin to a regular outlet - the hot water heater is wired directly into the main house panel
Yes, my heater plugs into a regular outlet. If you don't have one, that of course is impossible.
I think it comes down to heater size and voltage - mine is only 60 liters and 220V so can use regular wiring and amperage.
Just a note, you should heat the water up every now and then to kill any legionella bacteria.
Your spending more energy engineering that instead of just buying a tankless water heater if you care that much about it.
Depends… if you like to take your showers at peak times, the tankless might cost you more in opex (in addition to the capex).
More and more “tank” water heaters are moving to heat pumps which should use less electricity overall than a tankless (if you can handle the possibility of running out of hot water).
Which if you go that angle the capex on a heat pump heater regardless if hybrid or pure electric is going to negate any savings, those are typically 2-3x of a higher quality brand traditional water heater.
Which full circle going back to the original discussion of turning off the heater. You probably end up close to no/low savings. I can see an argument of a smart heater being able to slightly adjust load at peak times but I engineering a heater to turn off when you are sleeping and then heating back up before use is probably going to not have much savings. Those heaters are increasingly made to edge out at maintaining the heat and take quite a few hours to heat up.
Can you get tankless electric? I thought they were only gas
They definitely exist. I never had one and my understand it was they are generally not as great as the gas equivalent.
https://www.supplyhouse.com/Tankless-Water-Heaters-1060000
The cheap ones are fairly common in Britain where the user isn't choosing (student houses, cheap rentals etc). The installation cost is low, but the running cost is high.
They are crap. 8kW is typical, and the pressure for a reasonable water temperature is low.
I haven't knowingly used a more powerful one. I suspect that would negate the cheap installation cost, as it would need a three phase circuit.
Yes, You can buy an electric tankless but just be extremely informed of the large amperage requirement to instantly heat your selected gallons per minute flow.
Yeah you can find them on the Home Depot site. The largest ones use 36kW which is beyond a typical residence's electrical service. It doesn't save you any money if you need to upgrade your electric service.
https://www.homedepot.com/p/Rheem-Performance-36-kw-Self-Mod...
I have a very nice Graphana-based UI showing electric consumption data from Tesla power wall:
https://github.com/jasonacox/Powerwall-Dashboard
Together with temperatures in the rooms and AC activity:
https://github.com/cdzombak/ecobee_influx_connector
I plan to add a vehicle charging date to it (via Chargepoint Home).
I think Graphhana+Influx is a way to go for this type of projects.
Does ChargePoint have an accessible API?
OpenEVSE does.
A few years back I had a Sense power meter installed and its been great. It took some time to configure and get used to, and for it to detect various devices, but now I can reliably predict my upcoming power bill. And make adjustments as needed.
Whats helpful is it shows the top power consumers. And by paying close attention to that I've cut my bill by at least 1/3.
One project I worked on was to track indoor temperature and AC settings (via a Nest thermostat) and outdoor temperature (via weather report). I found that in the evenings I was often still running the AC even though outdoor temperature had dropped below my target. This alerted me that I should instead open my windows. I didn't have a way to track energy usage changes, but I was really happy to get so much more fresh air.
It stopped working when Google bought Nest and then changed their API authentication method. I had a newborn and just couldn't find the time to support the new API. Maybe I'll revive it this summer.
I've been making the same mistake. Another thing to note is warm air can pool in corners, so reversing fan direction or pointing a fan at corners helps
Few notes:
- fear and polemics about connected meters was not about "surveillance" by some giant but more about ability to disconnect or throttle a customer from remote and third party monitoring to elicit family habits for instance to organize a burglary;
- reading the meter without the need to get inside the home was already a solved problem with "telereport", a small local dedicated bus with wires going in some public places (like the hall of a condo, a small box near the portal of a home etc) who allow local reading, this could be used to send data remotely WITHOUT adding extra abilities like throttling or disconnecting;
- polemics exists for similar reasons for IVRE norms (BEV domestic charging) where the norms demand a kind of "remote control" to allow disconnecting the load from the grid when needed by the grid, without considering the few but not so few with domestic p.v. in self consumption that might get disconnected as well because there is no analysis of the grid absorption load just a "run this if the grid is strained";
- `Enedis website is nice` is well... debatable...
Beside this small notes NOT intended to diminish the author creation, IMVHO monitoring is useful only if you can act, for instance with p.v. and controllable appliances it's a good thing, and unfortunately there is next to none appliance really designed to run on p.v. when available, even 99% of those who claim the contrary. The first are domestic water heaters who actually could be piloted to shift load with HA/Shelly/* sometimes just abruptly cutting the power and giving it back when there is enough p.v. but not much more, secondary running dishwashers and washing machines left loaded and ready in a "run before 'given date and time' preferably on p.v. power" and so on. Technically such automation are damn simple and cheap if designed as part of every appliance but so far next to no one seems to be doing so, while mandatory monitoring and published monitoring solutions are more and more pushed. Personally having p.v. I do my best to shift loads and it's damn hard, mostly limited to smart switches connected to HA, because there is not much more to do. I can "hack" my dishwasher or washing machines, are dumb and basic enough to be easy just seeing their small controls and replicate them with a some GPIO on a raspizero and alike but that's a long uncomfy process since every machines have it's own controls and you have to redo when you change it. There is no standard.
Wouldn't it be cool if every wall and ceiling socket could report its electrical usage? I wonder if that's possible via powerline networks, or if it would work over something like Zigbee?
ZigBee could definitely do it but as someone with a lot of smart wall plugs (I have a total of ~40 ZigBee devices in my house) that data is just not really useful because it's just a drop in the bucket compared to cooling/heating/hot water.
One thing that would be more useful and that I really want to get is one of those amp meter for the distribution panel to see my power consumption in realtime: https://www.aliexpress.com/item/1005007038134809.html but I didn't get around to it yet.
I have two of these(1) Emporia Vue2 units in my home, one in each load center. I have them flashed with espHome and integrated into HomeAssistant.
I really love that they give whole home power usage, as well as up to 16 individual circuit usage details. And with espHome into HA, all local control with no cloud dependency.
(1) https://shop.emporiaenergy.com/collections/in-panel-energy-m...
This is what I've done; I use a Z-Wave power meter on my electricity meter for whole-home, then some individual ones for my desk/3dp/rack, the ~50 ZigBee devices I have are mostly bulbs or sensors (I also have another ~40-50 Z-Wave devices) and the majority are things that use very little power; the usage stats from those things is a rounding error.
For bulbs and sensors, the power usage isn't useful for automation either, you can use other data they provide (turn off lights when no one is around, do stuff when doors open/close).
For whole-home though, it can be useful to see if the power is higher than you'd expect; if it's not dinner time and we're using 2kW+ for more than a few minutes, send a notification in case someone left an electric heater or an iron or something on.
I'd appreciate smart plugs with bidirectional communication, as real-time power use report + ability to switch the plug = poor man's way to turn most devices into IoT devices for local control. It would help in particular with ones operated by IR remotes, which deliver commands but don't get feedback on their state; you could observe device's power consumption to infer the current mode of operation, providing a bidirectional control abstraction in e.g. Home Assistant.
Not sure if I am understanding correctly but getting power consumption and being able to turn the switch on and off is definitely available in even cheap ZigBee switches: https://www.amazon.ca/THIRDREALITY-Real-time-Monitoring-Comp... (~12$ each).
I used to work closely to this on whole home energy disaggregation. There are products for doing this, but the value is very limited.
Excluding EVs, heating and cooling is the largest factor for energy consumption followed by other large appliances. Small appliances and electronics don’t use much electricity or aren’t on long enough to matter.
If you’re interested in some product recommendations, the Sense Energy Monitor used to be a popular choice. Basically it is a set of clamps that you can attach at your breakers to monitor specific circuits. It’s good for monitoring large appliances with their own dedicated circuit. For individual appliances, a Kilowatt Meter works fine. If you want something for continuous monitoring long term, I’d look at the Eve Smart Outlet.
I have a Sense Energy Monitor. It works pretty well, but I wish they made their own smart outlets to integrate with the panel monitoring.
Anyways, some pretty clear trends emerge when tracking your energy usage. Climate control (heating, cooling, fans, dehumidifier) dominates my energy usage, then EV charging, the kitchen stuff (refrigerator, cooking, dishwasher), then electronics (and I have a ridiculous amount of them), clothes dryer and lighting. I would like more insights into my electronics for personal curiosity (which Sense can't seem to do), but in the scheme of things it probably doesn't matter. No individual electronic device is going to make much of a difference.
Not quite every socket, but iotawatt can monitor each circuit at the breaker panel, and from there, it's generally not too hard to figure out what's going on, and it's really nice to be able to get a concrete sense of where your electricity is going (for most people with a heat pump, it's mostly the heat pump, it swamps even our EV). It's local-only, no cloudiness, and it's been rock-solid for us.
This sounds pretty cool. I just went through the docs but I can’t tell physically how you install the CTs. Our mains come into the house underground and into the electrical panel and of course the wiring is all in the walls. Are you supposed to open up the walls and attach the CTs to the wiring in the walls? How would this even work for Romex that runs along framing?
You just turn off your main breaker, open up the panel, and snap the CTs/current transformers around one of the wires on each circuit (you can open them back up if you mess up). You only want to put one wire through, rather than a full romex bundle, because it measures the flux through the loop, and the return path would cancel out the reading.
It does take a bit of reading to figure out eg what to do with 240v circuits (you can usually double it if you don’t care about absolute precision, usually one leg has the control electronics on it and is a bit higher). Also, it doesn’t have quite as many channels as most panels’ max # of circuits, so you might have to choose, or try to run multiple wires through one CT.
If you’re uncomfortable with going into the panel (reasonable), you can probably find an electrician that’s willing to put it in/make it pretty.
I think I saw some YouTube videos of people installing them diy before I tried, that might help get you more comfortable with the process.
The CTs go inside your panelboard around each hot conductor. The CT leads go back to a separate meter enclosure.
Here’s a commercial grade submeter cutsheet with a diagram to illustrate: https://leviton.com/content/dam/leviton/lighting-controls/co...
You can definitely do this with ZigBee, I have smart light-switches that report usage; though I'd argue the lights are the least useful thing to have usage reporting for, since I already know the power consumption of the bulbs, and since I'm using LED everywhere, it's negligible compared to the rest of my usage.
The problem with ZigBee is network scale and interference, but also you're wasting energy by having electronics in every socket, always on, always reporting. You're also then driving your server harder and storing more data, costing more.
I've aimed to strike a balance of only making smart the things I actually care about power usage for; my server rack, my 3D printers, my desk, and then whole-home as a single unit.
I don't need to know how much my washing machine or oven uses, if I need to use them, I need to use them; there's little room for optimising.
When it comes to optimising which settings I use, if I care enough, I can use a temporary ZigBee power meter that plugs in like a normal device; record data for days/weeks/months and adjust based on the result of that.
Exhaustive data has nerd appeal, but in practice, you'd add power, circuitry, and RF noise overhead to mostly see signals that maintain very stable patterns for as long as the same thing is plugged into it and used in mostly the same way (i.e. for months or years).
All you really need is snapshot understanding of what a device really consumes, and only then if it's non-negligible and some alternative might make sense.
For outlets and receptacles, you can achieve that by just inserting a meter where you want. Per-circuit metering in the distribution/circuit breaker panel would be nice though.
You can get KNX switch actuators with per-channel True RMS / active power metering. They're like 40 bucks per channel.
There is a company that does this but senses direct from your circuit breaker panel. The uses FFT plus algos to determine individual devices on each circuit from their unique electrical signature. Called Sense I believe. I’ve never used it.
On a geek level it would be cool. On a practical level? My electric bill is $100 in January and $400 in July. I know what's going on.
if only! i know this is not what you’re asking for, but inexpensive Sonoff outlets flashed with firmware and reporting to Home Assistant are how i monitor (and switch on and off!) the largest consumers of electricity in my home. it’s a good two-weekend project
Not sure I really agree with all these design choices. The color scale on the hour/day grid initially seemed backwards to me. The daily total takes up so much space that it would be better as a normal line or point graph with scaled axes, instead of trying to guess the correspondence with the color.
Aside from that I am curious about the discontinuity at 22h. How many and what kinds of loads automatically respond to these price signals? Just heaters and water heaters?
> Aside from that I am curious about the discontinuity at 22h.
My water heater turns on during off-peak hours (so, at 22h). I have no other equipment that responds to the off-peak signal, so the discontinuity is entirely attributable to the water heater.
> The color scale on the hour/day grid initially seemed backwards to me.
I think it was one of the default color scales in Plotly. Maybe I got used to it, it doesn't strike me as reversed, but I think I see how it would feel that way for you.
> The daily total takes up so much space
That is true, though it didn't disturb me enough to bother changing its size.
While trying to skim the data, I kept wishing for a 3D or pseudo-3D "skyscraper" visualization, where height represents consumption.
Question for experts: I'm on SDG&E (North County San Diego) and apparently have a smart meter that supports HAN at 900 MHz, but at the end of last year SDG&E declared "no new devices [HAN devices] can be connected". Does this mean that if I want to monitor my electricity use that I’m out of luck?
A lot of smart meters also have a simple LED pulse output, that you can read with a light sensor.
That was just for local real-time monitoring iirc, using eg an Emporia Vue. I think you can still get the data from their website.
SDG&E supports "Green Button" downloads, but I wonder how long that will last — the links in the "Apps" section of https://www.energy.gov/data/green-button are dead, the official GitHub repo and Green Button Alliance repo appear to have gone into a coma around 2015, and Wikipedia doesn't have an entry for it.
If you live in the UK, you can sign up to https://glowmarkt.com/ and they'll give you the same 30 minute time slices, or you can buy one of their in-home devices for £70 (https://shop.glowmarkt.com/products/display-and-cad-combined...) and it'll push your usage every 10 seconds to MQTT to give you very interesting if completely useless graphs in Home Assistant.
(Not sponsored, I just use it)
How is this sustainable as the gap between self generated and stored energy and the grid price continues to diverge?
If present trends hold it won't be long before a few years worth of energy bills even in Europe finance a full off grid deployment. There doesn't seem to be much room to cut on the energy companies pricing which remains variable and pointlessly complicated vs "I bought this off grid system and now I never think about energy anymore".
Just people in high density housing, people in a lease, and those who can't afford the up front cost will constitute the majority of residential grid energy usage and purchasing?
Other than southern Spain, France, Italy and Greece, you're not going to run off-grid anywhere in Europe. Too little sun in the winter for heating needs. Unless you're considering small-scale wind power installations, but I cannot imagine what costs those could incur in installation alone.
Up in Orkney on vacation, the pretty constant wind all year (according to relatives) with a little solar, battery storage and heat pumps, I reckon off-grid might be possible. Add in starlink for internet and I might just stay here.
Not sure of the cost (need to do the research) but all of the above are getting cheaper. A small wind turbine can’t be that costly, surely.
Wind turbines in my research are pretty terrible unless run at scale (massive). YMMV but when I last looked into it, small turbines tended to be 1) noise polluters, 2) not very large power generators and 3) poor build quality.
small wind turbines have a terrible reliability and maintenance track record. They are not worth the investment.
The dilemma with wind turbines is that the small ones tend to be inefficient (and still much more expensive than solar), and large ones require huge up-front investments.
I'd love to be proven wrong about this though, if anybody has links to affordable wind turbines / generators, I'd be interested.
When I’ve looked into this before for a client in Scotland, it seems the smallest size that made sense in terms of the factors other commenters have mentioned was about £50,000 to install. Also it requires planning permission which is much harder to get for a wind turbine than for solar PV which you can often install without getting explicit permission under ‘permitted development’ rules.
Off-grid does not mean renewable-only.
You can run a generator to charge batteries or provide additional capacity when needed.
It would be ideal to have full coverage with "renewables" (isn't oil and gas a renewable just on a longer timeline?) but don't let perfect be the enemy of good if you want to move off-grid.
I do lack familiarity with the European environment, but between geothermal, wind, hydro and natural gas backup, is it really feasible as it is in places where solar gives 0.01 USD kWh prices?
Is geothermal an option?
That vicious cycle is a problem ever more expensive electrical grids will need to contend with over the next couple of decades.
The variable per Kwh costs are historically generally pretty low relative to the fixed capex and opex (eg. maintenance, idle runtime) costs.
Mostly this has been made palatable for residential use by hiding these fixed costs in a higher per-Kwh rate. This works great as long as consumption is high and growing. If consumption trends reverse, then self-generation becomes a real possibility for the heavy consumers leaving fewer total Kwh to spread the fixed costs over.
Left unimpeded this leaves the poorest with very high energy bills when everybody else has shifted to a private, cheaper, micro-grid.
Self-consumption can be envisaged, particularly for buildings with air-conditioning systems. In this way, you pay for part of the air-conditioning consumption with solar energy when you use it most during summer.
But operating completely disconnected from the grid, especially in winter, is extremely difficult. Luminosity is much weaker, the sky more overcast and the number of hours of sunlight reduced.
Anyone here use the NiceGUI Python web app framework the OP used? There is mention of Electron-like cross-platform ability, which I assumed meant that one could generate a standalone app with it, but I did not find mention of that in the online docs.
See here: https://nicegui.io/documentation/section_configuration_deplo...
I actually used that to build a Windows release: https://github.com/zdimension/elecanalysis/releases/tag/v0.1
It uses the system WebView to display the page. The packaging itself is made using a regular solution like PyInstaller.
You can get your data from the edf.fr site. In your account, under "Ma consommation d'électricité" there is a button "Télécharger mes données". It comes as a zip of csv files with daily and monthly values.
Has anybody figured out a way to do this with coned in the us?
Yes, Con Ed now has smart meters that report electricity usage in realtime at 15 minute intervals. If you use Home Assistant, you can perhaps make use of the Opower integration to get this data: https://www.home-assistant.io/integrations/opower/
Although implementing the realtime API in the Opower integration has not yet been completed. That said, I don't think it would be too hard to implement. See: https://github.com/tronikos/opower/issues/24
This realtime data is also available and graphed on your account page on the Con Ed website and mobile app.
I wrote my own code that uses Con Ed's realtime API and writes the data to Prometheus so that I can view it in Grafana. My code was heavily influenced by Home Assistant's Opower integration code. Here's my code: https://github.com/dasl-/pitools/blob/main/sensors/measure_e...
Alternative:
Build glow [1,2]for $10. Hook it up to homeassistant for the price of an old laptop. Measure any and all interesting plugs using an athom [3] smart plug.
Zero cloud. Good data & charts.
Good fun.
[1] https://glow-energy.io/
[2] https://github.com/klaasnicolaas/home-assistant-glow
[3] https://www.aliexpress.com/item/1005006078553282.html
As a former electrician turned software engineer and serial entrepreneur I have always been conscious of my utilities consumption. Per Lorde Kelvin one can only improve what one measures and there are many things most people in society complain about yet those individuals could improve if they just measured; the data doesn't lie, people do.
Around about 2006, after being in my newly built home for a few years, I began to ask the questions that many more are just starting to ask now about their utilities. Having had an extensive background in residential and commercial electrical work I knew the options then were limited to measure home consumption digitally but I stumbled upon TED, The Energy Detective. In 2007 I installed TED in my panels and it has been running ever since. I initially only used it as a curiosity item, much akin to many Tesla Solar+PW users today in checking the app for production and consumption data, never before available in such a simple near real-time form of access. TED did however earn it keep in helping me deduce electrical draw issues when systems within the house were changed alongside just other general consumption curiosity.
In 2016 I got serious and started logging all of my utilities at the first of every month directly from my meters and I also cross collected utility bill data into a spreadsheet. That spreadsheet is now large but the information is invaluable in providing me an aggregate collection specifics to me and my family only over that time. Another side story in itself are the errors I have discovered and reported, some of those errors have benefited me greatly, once again you can only know such things through measuring and monitoring. All of this effort was my LONG GAME preparation for going near fossil fuel free and energy independent at my home when I found the correct solution for my needs.
In 2018 we went fully electric with our personal road vehicles. I installed the largest wall charger at the time which supported 220V up to 70A. This of course spiked our home usage at times however free supercharging was a great bonus and still is. Yes, we were early adopters of a fully electric vehicle family now for over 6 years and have driven hundreds of thousands of miles combined across the U.S. and Canada. I am still amazed at how ignorant people are about charging infrastructure since the fossil fuel industry has brainwashed people's expectations with gas stations on every corner. I have referred many an EV owner and while the program no longer exists I still refer people to electric, just referred a CT a few weeks back.
As time passed so too did my roof age and those here aware of asphalt shingle degradation know builder selections rarely last. In 2020 I started down the solar roof planning journey which had me upgrading all aging appliances to EnergyStar and in August of 2021 the solar roof was installed with two PWs. This led me to refactor my spreadsheet to now include my personal generation and consumption which the new system was providing me. Here I mention the TED again because this old still functioning device had provided me with years of historical data and now I would use it to compare the numbers from the new system. Yes, I found discrepancies that no one had found before and those issues had to be resolved within the new system; a new more accurate CT device was required as well as firmware changes. You may be able to hear me still smiling from this near energy independent choice.
My choices have guided my curiosity which has guided my choices and this is still so extremely relevant today in that I have a unique energy loss problem of which I intend to solve through my own energy storage device I am building. Everything provable in life boils down to either science or math so if the science and math check out then it is only the implementation that matters to reach one's goal. I am applying my software, hardware, electronics, and electrical experience as a unique subject matter expert to build something that solves my problem through the dog-food method. Once I have hashed out all the basic issues with this simple "complex system" I am building I will then apply my entrepreneurial talents once again, that whole ‘serial’ thing. You likely know what happens next given the world's growing awareness of a pursuit that I have long had devoted interest in represented by the choices I have made solely from monitoring and measuring. Thanks Kelvin!
Stay Healthy!
So you have to go to a third-party to get your data from a public service. Absurdity is the word that defined our era it seems.
> "Depuis le passage à l'OAuth2.0, il vous faut obligatoirement avoir une entité juridique afin de signer un contrat avec Enedis. Pour avoir une entité juridique, il faut obligatoirement être une société ou une association."
> "Since the transition to OAuth2.0, you must have a legal entity in order to sign a contract with Enedis. To have a legal entity, you must be a company or association"
Yep, that's unfortunately the case for a lot of public entities. Open Banking is similar: at first you may think it means your banking data is open, so you can access it, as a consumer, through an open API... But Open Banking only makes banking data open for licensed data processors under very strict conditions and with quite stringent limitations.
I wonder if a situation similar to Letsencrypt could be setup in the Open Banking space. A non-profit (or something) entity with easy integration for consumers requesting data on their behalf.
What about requesting it under GPDR?
It's useful as information, but imagine having to wait a month for each API call !
Howdy HN,
My cofounder and I recently went full-time on GridLite, an app and website designed for NYC residents to help manage and split utility bills with roommates. We’ve just added a new feature that gives ConEdison users real-time access to their electricity usage with 15-minute interval data through our app. Perfect for anyone who wants to keep a close eye on their energy consumption. We'd love to hear your feedback from this community!
https://gridlite.co/