I'm on a electricity tariff where the per kWh unit price changes every 30 minutes, you're basically being charged at market rate or thereabouts, the prices for the next 28 hours are announced at 4pm every day.
Generally the prices betwen 4pm-7pm are expensive and the rest of the time it's cheaper - although with current world events things have gotten a little spicy lately.
On really windy days you definitely get to see the benefit where prices drop to zero or even negative, which is great if you have an EV or something to dump lots of power into. Looking at todays prices they're like 1-3p p/kWh!
But that doesn't last, as the wind dies things start to get back to normal.
The key with the tariff though is to just play the averages and generally avoid high power usage during the peak periods. My average for the last 2 years was around 30% cheaper (p/year) than what I would have paid if I was on a normal energy tariff.
It will be interesting to see whether that trend continues, especially with the state the world has suddenly been thrown into.
I wonder if we'll start to see gimmicks in home appliances for taking advantage of variable prices.
Like for EV charging I assume it's a basic requirement, you simply wouldn't buy a car that didn't let you adjust the charging schedule based on cost.
But what about... Freezers? Maybe there are scenarios where your freezer could drop 20° below its usual temp while prices are low, and thereby avoid running the compressor for several hours while prices are high.
What about a tumble dryer button that says "these clothes are fine to stay wet for up to 8 hours, dry them at the cheapest moment during that window"?
TBH I doubt these things would really pay for themselves but as a consumer I'd still be tempted by the "lol, neat" factor.
Also I assume the local-LLM heads are already finding ways to have their agents do useful work while the GPU can churn tokens for almost-free.
Also makes me think of fun Home Assistant workflows. Like, "when energy is expensive, just try to keep the house between 16-26°. When energy approaches free, I want to live at exactly 20°". (I assume heat pumps also have ways to take advantage of this in more roundabout ways).
I think freezers would definitely be a gimmick as they don't really use that much power.
I can see it being a nice feature for higher-load tasks though, e.g. my dishwasher uses about 1.8kWh for a cycle. On this tariff it's trivial to compute the best start-end time based on the 30 minute price windows, so if the dishwasher could do that it would be pretty sweet. Right now my dishwasher just supports a 3h delay function. I wouldn't mind if my dishwasher had a (local) API you could hit to control its schedule. Sadly this usually comes with some cloud requirement though.
Our Mitsubishi heat pump water heater has integration with some solar systems and weather services to attempt to time hot water production to solar peak.
We don't have solar panels but have a solar energy plan (cheap during the day, expensive during dawn/sundown, average overnight with fixed hourly schedule independent of actual production) so for us it's just programmed to follow a fixed schedule of prioritizing filling up during the solar hours and 100% forbidden from filling up during the expensive "duck curve" hours.
Things like freezers don't take a huge amount of power. It's definitely about things that do space heating/cooling. The traditional approach is to put your electric water heater on a timer. That way you can schedule your hot water use on a consistent schedule but only heat the water at night when you can be sure the rates are lower.
In my case I've got a contactor on the house power board that disconnects the hot water at night, so it's only heating off solar power. You can also get specialised solar diverters that do the same thing, but they cost literally ten times as much and only squeeze a tiny bit of extra efficiency out of the system.
If you do go down this path, make sure you insulate the crap out of the cylinder and surrounding water pipes, mine only heats once a day and that's once the sun's providing the power for it.
I second this. I live in Spain and put solar panels on my roof. I have no batteries. In the last 2 years, the price of the energy returned to the grid has been 0 or even negative. Therefore I started running automation using Homeassistant and I'm stuck at appliances that cannot be simply turned on and off with a power switch (i.e. my freezer, the AC, washing machine etc). If someone could produce a refrigerator that I can control via an open protocol(i.e. ZigBee) it would be awesome!
You can basically do that today if you wanted to by buying consumer grade batteries and smart switches. A whole house battery would be better, but it's more expensive to install.
For the tumble drier and dishwasher, those usually come with time delay features. That's usually good enough if your goal is to timeshift a load.
I have a battery for my fridge not for this purpose, but because I'd rather not have a power outage spoil my food.
With "smart" appliances that can be controlled, there's often a community integration to HomeAssistant ... and then there's the free EMHASS addon which will optimise for profit, or self consumption based on energy prices (both incoming and outgoing) as well as any on-site generation (e.g. Solar PV) batteries etc. etc.
Yeah, but that’s strictly worse for some of these examples. You can’t overcome the loss of energy just going into the battery and getting it back and the there is the huge cost of the battery itself.
The freezer example would require like $10 of electronics assuming there isn’t already a WiFi chip in it.
Many homes in Norway has this. Its a smart plug in your fuse box. For me it offsets EV charging untill the electricity is at its cheapest, it also cuts down on heating for the peak hours etc etc.
That's a great system. Like so many things, success comes down to implementation.
In California, for example, PG&E will charge you the maximum peak demand prices while simultaneously paying other states to take electricity during the solar duck curve.
I have an EV and am on a Time of Use rate plane here in SF. My lowest rates are between 12am and 3pm every day. I charge the car and run everything I can in terms of major appliance use between these hours (dishwasher scheduled to start at midnight or manually run early in the day, washer/dryer loads run in the morning). I am home during the day which makes this easier to do though. Another solution of course would be to bank your solar generation or low rate electricity into a set of batteries that you could draw from during peak times.
I'm on a similar tariff in the UK and just had a 10kwh battery installed which is just amazing for shaving off all the load between 4-7pm. Whole system installed was ~6k GBP and I think my payback time is going to be < 5 years which I'm super pleased with.
How are the fixed costs in this? Here in Sweden I have seen a strong trend that as the grid has become more variable and connected to the European grid, a larger portion of the bill becomes fixed. For most part of the year, the fixed costs are now greater than costs that scale with consumption.
Transmission and construction, crewing and maintenance of of thermal power plants (under the name of "reserve energy") cost a lot of money, which in turn becomes fixed grid costs. On top of that you got consumption costs during periods of poor weather, which in combination of high fossil fuel costs means that the consumption prices spikes. The cost of energy during optimal weather conditions is in contrast so low that at this point they can basically just be rounded down to zero.
My friend has a car which can charge only when prices are low. I'm not totally sure how it works though, does the smart meter communicate this to the car?
....that being said, when you see stuff like this page and news articles about cheap renewable power etc, there are A LOT of negative reactions to it (even evidenced by the comments on here!) because for most people in the UK they never really see any direct benefit - energy prices seem to keep going up and a lot of people are on contracts with fixed rates that rise often.
I'm not sure what the solution is, I know that the price of electricty is dictated by gas so maybe decoupling that will help - but that probably has complications with balancing the grid.
The tariff I'm on (Octopus Agile) suits me as I WFH, have an EV and it's just me living in the house, I can move my usage outside of hte peak periods quite easily and I built a website to help me find the cheapest charging periods for my car based on the prices for the next day. The other day my average unit rate was like 2p per/kWh and I dumped like 30kWh into my car lol
The key is factories ideally are mobile. Follow the winds. Come online and go offline when the wind blows. Use as much free energy as possible to hit yearly production targets and then take the rest of the year off.
Yet still it costs several pounds a day to heat your home in winter. People are going back to log burners. I've never seen so much coal/wood sold at the supermarkets during winter. I've got some electric blankets which is great but really energy costs seem to be spiralling.
This is a 'lawyer-worded' headline.
I am an enormous fan of renewables, I am an electrical engineer who designs control systems for renewables exclusively. My career depends on renewables.
Headlines like this do nobody any favors. The problem with renewables is that you cannot run a grid on renewables alone. Many days will have an abundant oversupply, like the day shown. Many days will not. Consumers are not tolerant of brownouts in the west. We need pump storage hydro, we need massive improvements to the transmission system, and we need battery storage plants (in that order).
Its fine to celebrate days of high renewable GW output, but people get out the GW Bush 'mission accomplished' banners a little early. The generation is the cheap and easy part. The rest is expensive and slow and needs way more focus than it's getting if we ever want to make progress in the west (China is already figuring it out)
Can people in Britain post their actual electricity rates per kWh?
I want us Californians to be able to see how badly we are (or aren’t) being ripped off by our utilities compared to you (mind you, these rates are approved by our regulator). We’re basically told we have to pay this much because of our lovely renewables requirements (they’re still far from 90% renewable though).
We are on a ‘time of use’ rate designed for EV charging at night.
We are paying 26 cents (£0.20) except for 4-9PM when it’s 59 cents (£0.44). Plus a monthly base charge which they just increased.
There are grid scale batteries on the UK grid. Surely they’re being used.
One could work out what the discrepancy between consumption and production during the day to infer the battery discharge rate, but I don’t think there’s anything there…
There has been talk, seemingly power generation dispatch a year or so ago was do e by phoning up the power station and saying “More amperes please Mr Woodbine”.
My understanding is this is being written to an automatic system which isn’t fully commissioned.
Grid battery owners a few years go were irate that they weren’t in the offing to sell power. But that must be resolved by now, since so much money is being invested in it.
Adapting to a fossil fuel free society damands to comply to some inconveniences, like to afford some days without or expensive electricity, to change the time of device use, even to be used to lower home temperatures. For me the most difficult part is to persuade my wife to comply. Fortunately I have solar/battery/netmetering and I only pay a small amount for the network use.
Could be higher - multiple Scottish windfarms are fully curtailed (developers paid for generation but the grid can’t distribute so they don’t use the power). Once the grid is upgraded with Easter Green Link 1-5 & Western Link 2, and the Scotwind Windfarms built this would be even higher!
And thats not how good renewables are- thats how deindustrialized britain has become. And deindustrialization leads to debt slavery - and debt slavery either leads to passing on that bitter chalice to others (empire) or to becoming a colony.
299 comments
Generally the prices betwen 4pm-7pm are expensive and the rest of the time it's cheaper - although with current world events things have gotten a little spicy lately.
On really windy days you definitely get to see the benefit where prices drop to zero or even negative, which is great if you have an EV or something to dump lots of power into. Looking at todays prices they're like 1-3p p/kWh!
But that doesn't last, as the wind dies things start to get back to normal.
The key with the tariff though is to just play the averages and generally avoid high power usage during the peak periods. My average for the last 2 years was around 30% cheaper (p/year) than what I would have paid if I was on a normal energy tariff.
It will be interesting to see whether that trend continues, especially with the state the world has suddenly been thrown into.
Like for EV charging I assume it's a basic requirement, you simply wouldn't buy a car that didn't let you adjust the charging schedule based on cost.
But what about... Freezers? Maybe there are scenarios where your freezer could drop 20° below its usual temp while prices are low, and thereby avoid running the compressor for several hours while prices are high.
What about a tumble dryer button that says "these clothes are fine to stay wet for up to 8 hours, dry them at the cheapest moment during that window"?
TBH I doubt these things would really pay for themselves but as a consumer I'd still be tempted by the "lol, neat" factor.
Also I assume the local-LLM heads are already finding ways to have their agents do useful work while the GPU can churn tokens for almost-free.
Also makes me think of fun Home Assistant workflows. Like, "when energy is expensive, just try to keep the house between 16-26°. When energy approaches free, I want to live at exactly 20°". (I assume heat pumps also have ways to take advantage of this in more roundabout ways).
I can see it being a nice feature for higher-load tasks though, e.g. my dishwasher uses about 1.8kWh for a cycle. On this tariff it's trivial to compute the best start-end time based on the 30 minute price windows, so if the dishwasher could do that it would be pretty sweet. Right now my dishwasher just supports a 3h delay function. I wouldn't mind if my dishwasher had a (local) API you could hit to control its schedule. Sadly this usually comes with some cloud requirement though.
We don't have solar panels but have a solar energy plan (cheap during the day, expensive during dawn/sundown, average overnight with fixed hourly schedule independent of actual production) so for us it's just programmed to follow a fixed schedule of prioritizing filling up during the solar hours and 100% forbidden from filling up during the expensive "duck curve" hours.
If you do go down this path, make sure you insulate the crap out of the cylinder and surrounding water pipes, mine only heats once a day and that's once the sun's providing the power for it.
For the tumble drier and dishwasher, those usually come with time delay features. That's usually good enough if your goal is to timeshift a load.
I have a battery for my fridge not for this purpose, but because I'd rather not have a power outage spoil my food.
Neat piece of open source software.
A heat pump house uses perhaps 40-50kwh in deep winter.
> A heat pump house uses perhaps 40-50kwh in deep winter.
Over what time period, and where? My geothermal system draws about 1200 watts when heating our large house on the coldest days of the year
The freezer example would require like $10 of electronics assuming there isn’t already a WiFi chip in it.
In California, for example, PG&E will charge you the maximum peak demand prices while simultaneously paying other states to take electricity during the solar duck curve.
https://www.eia.gov/todayinenergy/detail.php?id=56880
That seems counterproductive and exploitative.
Transmission and construction, crewing and maintenance of of thermal power plants (under the name of "reserve energy") cost a lot of money, which in turn becomes fixed grid costs. On top of that you got consumption costs during periods of poor weather, which in combination of high fossil fuel costs means that the consumption prices spikes. The cost of energy during optimal weather conditions is in contrast so low that at this point they can basically just be rounded down to zero.
I'm not sure what the solution is, I know that the price of electricty is dictated by gas so maybe decoupling that will help - but that probably has complications with balancing the grid.
The tariff I'm on (Octopus Agile) suits me as I WFH, have an EV and it's just me living in the house, I can move my usage outside of hte peak periods quite easily and I built a website to help me find the cheapest charging periods for my car based on the prices for the next day. The other day my average unit rate was like 2p per/kWh and I dumped like 30kWh into my car lol
>
Britain paying highest electricity prices in the world for second year running> Ed Miliband’s net zero targets are facing fresh scrutiny after Britain was found to be paying the highest electricity prices in the developed world.
> New data published on Tuesday showed the price paid by UK industry for power was 63pc higher than in France and 27pc higher than in Germany.
> Britain is also the second-most expensive country in the world for household electricity, with billpayers paying twice as much as those in the US.
https://www.yahoo.com/news/articles/britain-paying-highest-e...
In March, the UK emitted 161g CO2/kWh. France did 6 times less CO2/kWh with 2x less renewables !
https://app.electricitymaps.com/map/zone/FR/12mo/monthly
Headlines like this do nobody any favors. The problem with renewables is that you cannot run a grid on renewables alone. Many days will have an abundant oversupply, like the day shown. Many days will not. Consumers are not tolerant of brownouts in the west. We need pump storage hydro, we need massive improvements to the transmission system, and we need battery storage plants (in that order).
Its fine to celebrate days of high renewable GW output, but people get out the GW Bush 'mission accomplished' banners a little early. The generation is the cheap and easy part. The rest is expensive and slow and needs way more focus than it's getting if we ever want to make progress in the west (China is already figuring it out)
Bit more advances in grid scale storage, bit more interconnects and this looks real good
Discussion (didn't seem to get much traction): https://news.ycombinator.com/item?id=47553165
One could work out what the discrepancy between consumption and production during the day to infer the battery discharge rate, but I don’t think there’s anything there…
There has been talk, seemingly power generation dispatch a year or so ago was do e by phoning up the power station and saying “More amperes please Mr Woodbine”.
My understanding is this is being written to an automatic system which isn’t fully commissioned.
Grid battery owners a few years go were irate that they weren’t in the offing to sell power. But that must be resolved by now, since so much money is being invested in it.
Unless that is for non-grid power supply.
By their own data, today is about 18GW for wind, and this time last week it was 3GW.
But there’s a generation surplus and export of +13.4%!
If you add to that deindustrialization and buying everything from abroad and not caring where that energy comes from, it’s super easy.