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Comment by borodi | Hacker News Reader

The gemini solar project in Nevada is 700 MW power + 4 hours of batteries at 380MW and cost 1.9 billion. Took 2 years and that was in 2022

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Is 4 hours of battery an equivalent comparison to a nuclear plant?

I'm not anti nuclear or anything like that. It's just the financial comparison one has to make. Currently competing with solar + batteries is hard since unlike SMRs which hypothetically will get cheaper, they are getting cheaper at a quick rate and don't have the history of cost overruns that nuclear does.

I understand. My point simply is that the relevant price comparison is nuclear versus solar + enough batteries to make the solar plant equivalent to a nuclear plant. The battery system is the lynchpin of efforts to substitute solar for nuclear, and the cost/timeline of that should be factored in. But usually we just see an apples-to-oranges comparison of nuclear by itself and solar by itself.

Somewhere like Arizona/Nevada I would say it's getting pretty equivalent, In PNW or midwest region it's not equivalent at all.

4 hours at full tilt is pretty good, assuming that for the same volume you can store double the power in the next 15 years that means that you can replace those cells at end of service life and end up with 8 years ect.

When looking at costs, you have to also take into account the lifetime of the plants.

The current US plants are all getting extensions to 80 years of operation, and experts see no problems with going to 100.

How many times do you have to fully replace the panels in that timeframe?

How many times the batteries?

And what about seasonal storage?

> How many times do you have to fully replace the panels in that timeframe?

3 times, assuming current panel lifetimes. The panels will be even cheaper by then and will likely be robotically installed.

> How many times the batteries?

Maybe 4 times? Same as the panels; they'll be cheaper and easier to replace.

Maintaining and upgrading nuclear plants also has a cost. They don't last 100 years for free.

> And what about seasonal storage?

Might be unnecessary with enough overbuilding and grid interconnections. Or there might be cheaper storage technologies. Or batteries might become cheap enough that fewer duty cycles for season storage become economical.

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