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Comment by Scoundreller | Hacker News Reader

> 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.

View on HN

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.

> 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)

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.

> 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.

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.

>> 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

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.

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.

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.

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.

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.

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.

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.

> 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 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.

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.

"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.

Spreading out the capital costs to those better able to shoulder them.

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.

Nah just tax the rich and make it illegal for corporations based in a tax haven (like Ireland) to do business in our economies.

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.

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.

> 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...

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?

Reflowing PCB’s is one thing I can think of.

Drying out 3d printer filament is another.

Also heating up engine casings to get bearings in/out.

Drying 3D printer filament too (though I've not tried it myself and not sure I'd want to use my ovens for that).

I interpreted "non-meal" as anything except breakfast, dinner, supper. Like a cake

Yeah that was my take on it as well.

> 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.

> 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.

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...

I bet you could bring a lot of ice from the mountains for $22M.

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/

> 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

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).

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

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?

"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"

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.

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

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

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.

>> saving physical visits to read the meters

Why can't users read the meters themselves and send to the electric company once a month?

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.

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.

> 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.

> 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.

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.

> 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.

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.

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...

> 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.

2-4pm for me is about 6x the price of 2-4am. NYC.

https://fridge0.branchable.com/thermal_mass/

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.

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.

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.

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.

> 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

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.

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.

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.

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.

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.

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.

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.

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 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.)

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.

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.

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.

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.

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.

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.

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.

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