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The spot price is set according to the most expensive source but that is not the same thing as the price the consumer pays.

So for example, for wind power the consumer effectively pays the CfD strike price, largely irrespective of the spot price.

Fwiw, I do agree we have a problem with power being too expensive, but it's more complex than just the consumer pays the most expensive source.

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Look into a battery + inverter + optional solar on a time of use tariff, you can be always off peak. Payback probably isn't very long.
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Solar is great. I'm highly skeptical that a battery + inverter (w/o solar), using time-of-use for payback would ever make pure financial sense.

In fact, if it DID make financial sense, wouldn't companies already be buying up empty/cheap space and then turning a profit after the payback period? Why aren't they?

There are other reasons to do this, but purely on the financial side, I'd want to see the numbers on this one. Again, this isn't about solar, the claim was about battery + inverter + time-of-use paying for itself.

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Home batteries are much quicker to pay off than solar at the moment. This is largely due to being able to do strong arbitrage between import and export prices at different times of day, and some high guaranteed consumer export tariffs.

There’s no guarantee things will stay that way though, not least because the more storage added to the grid, the more those arbitrage opportunities get soaked up.

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Grid scale BESS (battery energy storage system) in the UK is growing fast, because it makes financial sense. There's one that just expanded from 100MWh/100Mw to 475MWh/350MW: https://www.pacificgreen.com/energy-parks/energy-park-case-s... . It's easy to run the numbers, easier to make a payback calculator with AI. Take a look at the Anker E5000 / Ecoflow Stream 5000, and run the numbers yourself, I'd be interested to see what the payback would be for you.
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> I'm highly skeptical that a battery + inverter (w/o solar), using time-of-use for payback would ever make pure financial sense.

Ever? Batteries are 10x cheaper today than they were ~a decade ago. If that trend continues for even a little longer, they'll be absolute no-brainer like solar is today within the next 5 years.

2026 seems to be roughly the break-even point. And whether it's worth it depends on where you live (greatly affects the cost of both installing a system, and buying energy from the grid).

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Has anyone done this on the cheap? I've gotten a few quotes with a payback period of 8-12 years, which isn't great.
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Yeah, I bought an inverter from eBay, and a battery from AliExpress. Also signed up to axle energy to reduce payback period. Most people would need an electrician to connect it though. If you just asked an electrician for a new circuit with a simple route to an isolator, it wouldn't be expensive.
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Can't - building prohibits everything along those lines
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In the UK, solar is fairly ineffective in the winter as the sun barely comes over the horizon for not many hours a day.
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I import more than I export in December and January, but for every other month of the year it’s the reverse by some margin. My annual electricity bill is net negative, and the installation cost will be paid off in 7 years. The numbers would be even better in, say, Spain, but they are perfectly adequate here, despite suboptimal latitude.

Incidentally, the grid only knows about my exports. Self-consumption manifests as demand reduction, so UK solar production and electricity consumption is probably higher than aggregate figures suggest.

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True, but if you get cheap power from solar for the rest of the year, and charge the battery from the grid off peak when there's no solar to charge, you should end up paying less than just the standard rate.
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Balancing auctions are pay-as-bid, the alternative is lights-off.

Capacity auctions are iirc pay as clear. Maybe day ahead as well.

One thing to consider as well is that without some external stimulus scheme all of the fossil/nuclear (even ignoring CFD schemes) would immediately go bust IIRC if the market was solely pay-as-bid because wind and solar are cheap but extremely spotty so the price would either be 0 or 1000, probably not the latter long enough to keep the gas plants we currently rely on in business => no more power on cold calm nights.

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Well whatever the hell they're doing on pricing it's not working. Having huge amounts of wind, strong interconnects, gas fields near by and still ending up tied for 3rd most expensive elec is ridiculous. Especially given how good storage is looking relative to gas lately [0].

https://www.statista.com/statistics/263492/electricity-price...

[0] https://www.reddit.com/r/technology/comments/1x0tds4/4hour_b...

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