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UK retail electricity prices hit -19p/kWh today (github.com/jonatron)
38 points by jonatron on July 2, 2023 | hide | past | favorite | 66 comments


Psssh, that's nothing. I've got €-0.43/kWh here in the Netherlands for 3 hours today, including tax. Energy prices are negative from 11 to 17 today.

And it's not all that sunny. A Sunday of course so lower demand. I'm going to switch of my solar panels. We have a dynamic tarif, so I actually get these prices and will pay to deliver power.

Net metering in the Netherlands makes it not relevant for most people to curtail their solar panels. Apparently we have the most installed capacity per capita in the world, die to these incentives. They did their job, time for a next step: storage.


You're right to be proud of the NL installed solar capacity per capita but I have to mention you're second behind Australia. PDF[1]

No one gives away money for PV systems like Australia. Long may it continue.

[1] https://iea-pvps.org/wp-content/uploads/2023/04/PVPS_Annual_...


Australia is a huge country with plenty of sunshine, unlike the Netherlands.

That's why the Dutch achievement is the more impressive one.

Still, great job to both countries!


We'll I'll be damned, Dutch Twitter lied to me


Interesting - so presumably you could also make a small amount of money by turning on e.g. a bunch of electric heaters. Makes me wonder whether someone could (or is) making significant money this way.

It's amazing to me there isn't some better way of using this energy in energy intensive industries e.g. electrolysis


Charging an electric car will earn you €10-€15 and you get to drive your car a nice distance too.

Battery storage could earn you more if you discharge at the right moment, but energy prices aren’t negative often enough to warrant the expenses on a battery pack. You could also trade on intra-day pricing differences (buy low, sell high) but I doubt this will be an interesting business case for the average consumer.

Of course large scale battery parks work the same way, but they will have contracts with the grid provider to balance capacity, a more lucrative market.

Large scale electrolysis has the same problem as home batteries: big investment, so you won’t recoup the investment unless you can run the electrolyser often enough. Another issue is that electrolysers can’t scale up or down very quickly, so you can’t respond to capacity issues and get lucrative deals in that market.


I think the main issue is predictability of price/power? If you could guarantee getting paid 10p unit for off-peak, and guarantee getting paid 40p to supply during peak, for say 5 years, I think a lot more of these projects would take off...but it's all still far too turbulent.


The thing is: batteries, when used for buying low and selling high only in a turbulent market, have a dampening effect on exactly that. So, if deployed en-masse, they kill their own business case. With the 'side effect' of a much more stable price market, which is exactly what we want I guess.


Sounds like the Cash for Ash scandal, which took down the Northern Irish government: https://en.m.wikipedia.org/wiki/Renewable_Heat_Incentive_sca...


Ppl make money (an insignificant bit) by charging their car. Like €15, while the car cost is easily €3-40k


Assume this every day and pays itself multiple times over the lifetime of car


Then still, you'd need 5 to 8 years of very negative prices. These prices are a nice little bonus for some ppl but not something sustainable. It's a signal from the market something has to change: be more flexible, in demand or supply.


By "bunch of electric heaters" do you mean GPUs and such?


GPUs cost a lot to exploit a small price issue like this. I would use a dirt cheap heat element heater - presumably you could acquire these very cheaply and get paid to use power.

The problem usually is that there's a physical cap on how much energy can be transmitted through a grid endpoint, and grids themselves charge a significant portion of the bill, meaning arbitrage only works if the actual price is eg. -14c (the case in my particular location)


Might as well start mining some bitcoin while you wait for storage


I live off grid, and have more than my batteries can take. I considered just doing a hot water cylinder for the excess, but I’m currently instead working on a hot water cylinder heated by GPUs. May as well do some useful work while making my shower hot.


Was thinking about this too. Or mining Bitcoin and using that wate heat etc. There's heat pump boilers apparently with some additional loops for external heating (meant for solar water heaters) that could be used for this.


It's windy though. I'm seeing the windmills doing their job.


I thought about this and negative energy prices make no sense whatsoever to me.

I get the whole "free market" idea, but this conveniently ignores all externalities, as well as the cost of subsidies. For example, if subsidies were used to buy generating capacity (like solar panels), subsidies should be (partially) recovered.

We have too many "free markets" where we ignore the cost of externalities.


Subsidies are fixed costs. They are not investments, they are one time payments. Under certain conditions, you have to pay those back, but these are commonly not related to pricing.

I don't know how much you know about energy grids, but there is a big reason why negative prices are needed. Energy can't float around on the network. It needs to be used (by direct usage, or storage). If there is too much energy on the grid it needs to be used. There's two ways to solve this, being stop energy from being pushed to the grid, or consume more energy. Both lead to negative pricing to create an incentive to achieve this.


I may be wrong, but I don't think this is accurate.

If the goal were to consume excess production, power plants could just heat a pool of water on-site, or some similar industrial scale "pointless" electricity use.

Rather, negative prices are there because it's in the interest of energy producers to shift demand from the peak, as all their infrastructure needs to be scaled to meet that demand.

So don't think of it as free energy at the time you're using it, think of it as a fine for running your washer/dryer etc. during peak hours.


This isn't that rare once large enough portion of production is wind/solar. Sometimes there just is "too much wind" and you get 0 or negative prices.

For example today we got to -5c/kWh in Finland and it will be negative most of the day. Currently hydro is scaled down by ~1500MW and nuclear ~600MW. Also a bunch of wind is probably turned off due to the negative prices (there is enough wind today to almost max the total wind production of 3200MW today but only ~600MW in use at the moment)

https://www.fingrid.fi/en/electricity-market/power-system/

Though not all electricity is bought/sold on the spot market but instead a lot of consumers are on fixed rate contracts and the companies usually buy futures to cover most of the fixed price contracts they have.

This is also why there is now a lot of investment in storage and hydrogen. Basically as more and more renewables (mostly wind here in Finland) is being built they want to buy this negative (or 0) price electricity and make money by selling it later. Though even negative electricity costs to use due to taxes (0.063c/kWh for industrial usage) and transmission fees (between 4 to 10c/kWh depending on location)


I hope we’ll get automation that’ll allow us to adjust demand at scale. It’s a shame smart meters have such a bad rep in Europe due to the privacy issues. I’d like to have a water heater that maintains a range, goes to the maximum when energy is cheap or free and the minimum otherwise. Dishwasher and integrated washer dryers could be loaded and waiting to start during the time of the day where there’s excess energy. Some of this is coming as part of solar on everyone’s roof to maximize the ROI but we could do much more.


> It’s a shame smart meters have such a bad rep in Europe due to the privacy issues.

They've got a bad rep because they're some proprietary computer with a cellular modem transferring who-knows-what back and forth to the mothership.

My power company (in .nl) wanted to install one, and I rejected it on that basis.

It would be trivial to implement what they're supposedly doing without relying on user-hostile technology and autonomous phone-home.

But what you're mentioning doesn't require smart meters at all, you could just e.g. poll prices online, and at the bottom of the curve turn on the power socket to your dishwasher with ZigBee. You'd just need a dishwasher that would start as soon as it got power.

Smart meters are there to phone home about your consumption in real time. They're mainly there to benefit the power company, any ability to inform your own consumption is incidental.


Presumably it's because the jet stream is currently over Britain and the wind farms are actually producing a significant amount of power:

https://renewables-map.robinhawkes.com/#5/55/-3.2


This happens almost daily in California — it’s called the “duck curve” and prices peak dusk and dawn, stable through night, and go negative during the daytime from excess solar.

You could often profit in CA by just arcing electricity into the ground, at least until more storage capacity comes on grid


Maybe a stupid question, but who is producing for negative prices? Wind and solar should be easy to shut off. Gas power plants, too - at least in a matter of hours. So does all this energy come from massive coal and nuclear power plants that can't shutdown quickly?


Yep, pretty much coming from power plants that cannot shutdown quickly or economically. Sometime it's much cheaper to pay someone to use it up than shutting and bootstrapping again.


Imagine if by law you need to bus people from A to B every hour, but they get to pick when the trip takes place, but you need to buy and maintain the bus.

Your bus can accommodate 40 passengers.

At 2-5 in the morning you get only 5 passengers, at peak hours you average might occasionally get 32.

If you could induce passengers to shift their habits such that you could be a small bus with a capacity for 30 people your infrastructure costs would go down.

So maybe you're charging $5 per trip on average, but $-5 off-peak, and $20 during the peak.

Other comments here point out that some power plants can't be easily scaled down, that's also true, but the system is also intended to shift overall demand over the long term.

So nobody's producing for negative prices, rather a peak hours consumer is directly subsidizing other customers, because the power company would like them to shift their consumption.


Many old wind farms still have a subsidy for several years that makes it profitable for them to produce even with some negative prices.

Coal seems to be shut off: https://grid.iamkate.com/


Nuclear power plants always being on means they need more government subsidy than wind farms. The company running them demands a minimum guaranteed price. Free market indeed.

It's funny how far wind power has come- courtesy of the almost always windy North Sea.


I imagine there are contractual commitments and SLAs involved.


yes, plants that are too expensive or too slow to shut down temporarily (have to) produce for negative prices.


It will be very interesting to see how the renewable energy transition will play out. Energy drives the economy. Zero price energy is something akin to zero interest rates.

While abundance is a positive, it also makes all sort of absurd projects feasible.

In the short term we have a storage problem but I dont think this be an issue for much longer.


It's a guarantee that hydrogen production will take off, and in the long-run disrupt basically everything else. All of the critics are trapped in the mentality that green hydrogen will always be expensive. They are totally oblivious to the possibility that it could be practically free.

But it will be practically free, or at least close to it. And that's the problem for all possible competition. How do you compete with something that is either free or close to it? You can't. So in long-run, anything that can be directly displaced by hydrogen will be driven out of the market.


For every 10 absurd projects we'll get 1 good one and for every 10000 we'll get a revolutionary one.

Energy usage is the hallmark of an advanced civilization. There's literally a SciFi (scientific?) scale for it.

https://en.m.wikipedia.org/wiki/Kardashev_scale

On the other hand, as batteries advance, expect killer drone swarms to commit all sorts of atrocities and cars to become HUGE.


Provided that absurd projects pursued as collective obsessions don't drown any good ideas. Energy is just one ingredient. Human attention, capability and committment is maybe the essential element and its typically grossly under-utilized.

With abundant energy we get (in principle) global electrification, with that we get global digital interconnection and (again in principle) a uniform educational level. But with technology the positive scenario just never seems to be the one that actually materializes.


> and cars to become HUGE.

When oil prices rallied last year I saw an increase of gas-guzzlers on parking lots with a large FOR SALE sticker, but I'm not entirely sure the converse is true.

The number one driver of size in cars has been safety - either mandated or just perceived.

I suspect that, if anything, with abundant energy cars might become cheaper or made using more exotic materials like CFRP or anything borrowed from Formula 1.


> The number one driver of size in cars has been safety - either mandated or just perceived.

Yeah, and what will change about this trend? Do you think all of a sudden people will want cars perceived as unsafe? If bigger is perceived as safer, bigger is what we'll get. People will just get bigger and bigger cars, up to the limit of lane widths, parking spot lengths, etc.

> I suspect that, if anything, with abundant energy cars might become cheaper or made using more exotic materials like CFRP or anything borrowed from Formula 1.

Ok, bigger and lighter up to a point. But guess what, car engineers will just use the weight budget to add seat heaters and coolers, 20 subwoofers, etc.

> When oil prices rallied last year I saw an increase of gas-guzzlers on parking lots with a large FOR SALE sticker, but I'm not entirely sure the converse is true.

We've seen this before with the 70s oil crisis. Car sizes went down, then as soon as times were perceived as good or prosperous, car sizes went up.

The VW Golf of 2023 (compact European hatchback) is bigger than the VW Passat of 1973 (mid-sized sedan).


It was because the wind was blowing and solar was doing well. At 14:30, wind was 15GW and solar 7GW against demand of 28GW. Nuclear was an additional 5.3GW. See https://grid.iamkate.com/. I don't know the specifics of why this results in such negative prices, but it's relatively unusual to have both high solar and wind simultaneously, and it happened at the weekend when demand is lower.


So what does this mean? Someone produced too much electricity, and the network had to find a way to get rid of it, so they were willing to pay consumers to take it? Makes sense.

So now my question is, consumers aren't looking at electricity price in real time[1], so making negative isn't going to get consumers to consume more. So what's the point of making it negative? It's not gonna help you achieve your goal of getting rid of it.

[1] Marje we're going negative!, get the extra kettles out of storage!


I can only speak for myself but I've rearranged a few household jobs to take advantage of the negative prices today. I'm not going to miss an opportunity to be paid to use energy.


What, do you normally have electricity prices streamed to your phone or something?


The inputs and outputs of the grid need to be balanced. A large proportion of the UK's grid inputs come from renewables - wind and solar - that can't easily be controlled. That's leading to increased supply volatility and so increased price volatility, which in extremis results in (previously unheard-of) negative prices.

Consumers aren't looking at prices in real time, but industrial users are. Let's say that you run a large cold storage facility. You need to maintain temperatures within a safe range, but that gives you some responsiveness to real-time prices - you could push towards the low end of that range when prices are low, or drift up to the high end of that range when prices are high. In effect, you're using the temperature of your warehouse as an energy storage system. The same would apply to many industrial processes that involve heating, cooling or pressurised fluid.

As we transition towards 100% sustainable energy, we hope to exploit much more of these non-obvious sources of energy storage through dynamic pricing and smart appliances. If you charge your electric car overnight, you don't actually care when it draws energy from the grid as long as your battery is full in the morning. A smart charger could wait until prices are low in the dead of night, or even feed back some energy to the grid during the early evening. You probably won't notice if your air conditioner or your heating drifts beyond the set temperature by half a degree, but the grid most certainly will notice millions of smart thermostats that can reduce grid demand during brief peaks.


> Consumers aren't looking at prices in real time, but industrial users are.

The headline says retail though.


people with battery systems or EVs are, or at least the batteries usually are: this provider has integrations with most home batteries. Storage heaters are another potential sink, though less useful this time of year.


If you’ve still got an insulated hot water tank with an electric immersion heater just dump excess solar generated electricity into that - you can always treat yourself to a good soak in hot bath!


I'm not actually doing this as I don't currently have access to negative prices, but I do have a battery in my home, so at least in theory it would be possible for me to charge during negative price times to use the power for peak times. Even better would be to charge my electric car during these times.

This does highlight the fact that we need smarter / more configurable home systems, since the decisions about what to do with solar / grid / battery / car can get fairly complex.


I'm thinking we need even smarter meters/battery chargers etc that monitor the current price. Or -eg- rig up the washing machine to a pi/arduino/other or so to start up once the price hits 0 at a negative dp/dt (where p is price). Now it makes sense for some electronics to have a network connection for this kind of info!


Presumably industrial consumers are looking at pricing and will decide to smelt more aluminum or something when it's cheap.


Aluminum smelting isn’t all that dispatchable.

During times of crisis, it can be idled, but the reduction units aren’t designed to turn on and off subject to the whims of the market- capital equipment and labor to run it aren’t going to work at a 10 percent duty factor.


Pumped-storage hydroelectric power generators (e.g. https://en.wikipedia.org/wiki/Dinorwig_Power_Station) use cheaper prices to pump water up mountains.


It's likely subsidies that still make it profitable to produce even at negative prices.


It is long term contracts, not subsidies (which obvoliously are a type of long term price gurantee in most cases) alone. From what I read from Germany before, local grid shortages may further contribute. Since the price is constant in one grid zone but demand may be higher in some nodes, local variable producers may have to be online even though it costs them money to generate.


I’m looking at it in real-time, and my provider sends me a notification if price drops below a certain threshold. So things like charging the car or bothering to run a pyrolytic clean of the oven definitely happen in these circumstances.


How much does it cost to charge your car from 0 to 100% at the average price?


The prices I’ve seen over the last year range from –US$0.05 to to US$0.88 per kWh depending on what’s happening with the supply. So there’s really no average, it depends completely on timing. But worst case it’ll be around US$50. That’s about the same price as filling up a petrol car though at current prices.


idk about uk but around here spot prices are released on the previous day. that is enough time to allow scheduling your day to run eg laundry or dishwasher during best hours, or at least off-peak.


There are a few dynamic pricing energy retailers in Australia too. It often goes negative, sometimes for many hours at a time. Usually it’s hard to make money off it because it’s often at times of the year and day that there is no need for heat/cooling.


I’d be curious what changes people are making to their routine to cope with a service like Octopus Agile.

I have a fairly extensive smart home setup so toggling devices off during peaks is easy, negotiating with the wife is going to be more challenging.


How do I get access to this pricing? I'm sure everything I looked at was fixed price or at best off-peak/peak pricing


It's a tariff called Agile Octopus: https://octopus.energy/agile/


I can’t talk about the UK but in Austria you need an hourly contract and a smart meter. If you have a PV system and you want to min/max electricity you need some smart systems to regulate self consumption vs. feeding back.


As others have said you need a tariff that's hourly, be warned though people got bitten with this when prices soared to many pounds per kW/h, it's not always this low.


The most common tariff that offers these prices is capped at 100p/kWh (about 3-4x higher than the standard price). I've been on it for about 3 months and I never saw anything higher than the standard price.


You need to be on a tariff that tracks wholesale prices like the Octopus Agile one.




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