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I'm in the UK and am currently being paid to use electricity. My energy provider uses a tracker tariff which can change every half hour (it does have a maximum

by edent 6mo ago

I'm in the UK and am currently being paid to use electricity. My energy provider uses a tracker tariff which can change every half hour (it does have a maximum cap to prevent the issues seen in Texas). Prices are currently negative, so every kWh I use right now means the electricity company pays me. Nuclear promised energy which was "too cheap to meter". But solar actually delivered.

jonatron 6mo ago
Batteries are getting affordable too - Fogstar do a 16kWh battery for around £2000. Plus, grid scale iron-air batteries sound promising.
- thebruce87m 6mo ago
  Have you got one? Looking for installation options.
ahhhhnoooo 6mo ago
If you had a big enough battery, could you sell electricity back to the grid later? Get paid to charge the battery, get paid to discharge the battery? It seems silly, but actually... it's driving useful behavior I suppose. Then again, maybe a good government would notice this and just fast track grid storage rather than distribute that work to all the citizens.
- fhn 6mo ago
  Sure you could. How much do you think they will pay you per kw? 1/10 what you paid them and they will charge you for using their infrastructure..at least in the US they do.
- jonatron 6mo ago
  > If you had a big enough battery, could you sell electricity back to the grid later? Get paid to charge the battery, get paid to discharge the battery? Yes, some people do this. There's even a startup built around the idea: https://www.axle.energy/ https://www.axle.energy/
- Maxion 6mo ago
  Overall on it's own that isn't yet profitable to do, unless you're e.g. a wind producer.
- cjrp 6mo ago
  Yes, I believe some EVs allow this too.
  - modo_mario 6mo ago
    I don't think that would ever commonly be viable or at least not for a long time. EV's are a lot more than batteries and are proportionally stupidly expensive. If the electricity net arbitrage was worth the degradation of the battery then .... companies would do it themselves and just build the batteries for cheaper at scale.
    - edent 6mo ago
      It is commercially viable. A UK energy company already has a Vehicle to Grid tariff. https://octopus.energy/power-pack/ https://octopus.energy/power-pack/ See also https://www.ofgem.gov.uk/publications/case-study-uk-electric-vehicle-grid-v2g-charging https://www.ofgem.gov.uk/publications/case-study-uk-electric...
      - modo_mario 6mo ago
        >A UK energy company already has a Vehicle to Grid tariff. And is that actually worth it to anyone who does the math? An optimistic 161 pound saving compares to how many of my battery cycles for example? My car costs 50-60k so battery degradation is not nothing.
        edent 6mo ago
        Yes. The arbitrage difference between filling your battery cheaply and discharging when prices are high is greater than any theoretical wear on your battery. Even better if you are being paid to charge your battery.
    - benj111 6mo ago
      The battery is already a sunk cost. Doesn't matter how expensive the battery was if it's already sitting on your drive. I did a quick fag packet calculation and even today 10% of everyones EV battery would be enough to cover the grid for an hour. That's enough of a buffer to spin up gas turbines for example, so you can actually shut them completely off.
- edent 6mo ago
  Yes. I have a 4.8kWh battery which is slurping up electrons. It charges either from our solar panels or from cheap grid electricity. It discharges when prices are high. So it'll mostly go into my oven tonight. If export prices are high, it can also sell back. Very roughly, we sell about 16% of our stored electricity - the rest is used by our home. See https://shkspr.mobi/blog/2026/02/30-months-to-3mwh-some-more-home-battery-stats/ https://shkspr.mobi/blog/2026/02/30-months-to-3mwh-some-more...
- rcxdude 6mo ago
  A lot of the value to homeowners is essentially arbitrage on the retail cost of electricity: when prices are high you're going to be paying a lot more to pull electricity from the grid than you would be paid to supply it, so you're better off using up the buffer yourself as opposed to paying for electricity from the grid.
- dehrmann 6mo ago
  Someone at the utility went through the same math you are and decided it isn't worth it at scale. It's probably not worth it at small scale.
  - ZeroGravitas 6mo ago
    The UK is world leading in battery rollout because someone did the sums and decided it did make sense at scale.
    - dehrmann 6mo ago
      Or it is! And they can do it cheaper at-scale than you can.
  - beng-nl 6mo ago
    Back of the envelope I did one time told me i could earn more by picking up cans off the street and trading them for the deposit. Still, it would feel nice - after the initial cost- to have very cheap power (only charge when cheap).
  - crote 6mo ago
    There is no such thing as "the utility" in Europe. It is legally not allowed for a single company to both operate (parts of) the grid and trade in electricity.
- benj111 6mo ago
  Like an EV....
pixxel 6mo ago
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by edent 6mo ago

jonatron 6mo ago

Batteries are getting affordable too - Fogstar do a 16kWh battery for around £2000. Plus, grid scale iron-air batteries sound promising.

thebruce87m 6mo ago
Have you got one? Looking for installation options.

ahhhhnoooo 6mo ago

If you had a big enough battery, could you sell electricity back to the grid later? Get paid to charge the battery, get paid to discharge the battery? It seems silly, but actually... it's driving useful behavior I suppose. Then again, maybe a good government would notice this and just fast track grid storage rather than distribute that work to all the citizens.

fhn 6mo ago
Sure you could. How much do you think they will pay you per kw? 1/10 what you paid them and they will charge you for using their infrastructure..at least in the US they do.
jonatron 6mo ago
> If you had a big enough battery, could you sell electricity back to the grid later? Get paid to charge the battery, get paid to discharge the battery? Yes, some people do this. There's even a startup built around the idea: https://www.axle.energy/ https://www.axle.energy/
Maxion 6mo ago
Overall on it's own that isn't yet profitable to do, unless you're e.g. a wind producer.
cjrp 6mo ago
Yes, I believe some EVs allow this too.
- modo_mario 6mo ago
  I don't think that would ever commonly be viable or at least not for a long time. EV's are a lot more than batteries and are proportionally stupidly expensive. If the electricity net arbitrage was worth the degradation of the battery then .... companies would do it themselves and just build the batteries for cheaper at scale.
  - edent 6mo ago
    It is commercially viable. A UK energy company already has a Vehicle to Grid tariff. https://octopus.energy/power-pack/ https://octopus.energy/power-pack/ See also https://www.ofgem.gov.uk/publications/case-study-uk-electric-vehicle-grid-v2g-charging https://www.ofgem.gov.uk/publications/case-study-uk-electric...
    - modo_mario 6mo ago
      >A UK energy company already has a Vehicle to Grid tariff. And is that actually worth it to anyone who does the math? An optimistic 161 pound saving compares to how many of my battery cycles for example? My car costs 50-60k so battery degradation is not nothing.
      - edent 6mo ago
        Yes. The arbitrage difference between filling your battery cheaply and discharging when prices are high is greater than any theoretical wear on your battery. Even better if you are being paid to charge your battery.
  - benj111 6mo ago
    The battery is already a sunk cost. Doesn't matter how expensive the battery was if it's already sitting on your drive. I did a quick fag packet calculation and even today 10% of everyones EV battery would be enough to cover the grid for an hour. That's enough of a buffer to spin up gas turbines for example, so you can actually shut them completely off.
edent 6mo ago
Yes. I have a 4.8kWh battery which is slurping up electrons. It charges either from our solar panels or from cheap grid electricity. It discharges when prices are high. So it'll mostly go into my oven tonight. If export prices are high, it can also sell back. Very roughly, we sell about 16% of our stored electricity - the rest is used by our home. See https://shkspr.mobi/blog/2026/02/30-months-to-3mwh-some-more-home-battery-stats/ https://shkspr.mobi/blog/2026/02/30-months-to-3mwh-some-more...
rcxdude 6mo ago
A lot of the value to homeowners is essentially arbitrage on the retail cost of electricity: when prices are high you're going to be paying a lot more to pull electricity from the grid than you would be paid to supply it, so you're better off using up the buffer yourself as opposed to paying for electricity from the grid.
dehrmann 6mo ago
Someone at the utility went through the same math you are and decided it isn't worth it at scale. It's probably not worth it at small scale.
- ZeroGravitas 6mo ago
  The UK is world leading in battery rollout because someone did the sums and decided it did make sense at scale.
  - dehrmann 6mo ago
    Or it is! And they can do it cheaper at-scale than you can.
- beng-nl 6mo ago
  Back of the envelope I did one time told me i could earn more by picking up cans off the street and trading them for the deposit. Still, it would feel nice - after the initial cost- to have very cheap power (only charge when cheap).
- crote 6mo ago
  There is no such thing as "the utility" in Europe. It is legally not allowed for a single company to both operate (parts of) the grid and trade in electricity.
benj111 6mo ago
Like an EV....

pixxel 6mo ago

[dead]