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You’re in a thread about California adding record amounts of battery storage. These batteries charge at noon a discharge in the evening while demand is peaking. This smooths out the supply across the day so it can meet the demand.

California did struggle with the duck curve but it’s less of a problem now. When the next heatwave comes, evening aircon demand won’t be a problem.

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> California did struggle with the duck curve but it’s less of a problem now. When the next heatwave comes, evening aircon demand won’t be a problem.

The point of my top-level comment was that we don't actually know that. Not yet.

I'll be thrilled if that's the case. I'll also be very surprised.

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GP is basing their comment on 5 year old data. As of April 2025 the duck curve problem is solved - https://blog.gridstatus.io/caiso-solar-storage-spring-2025/. Mid day demand increased because of battery charging, smoothing out the load. The California grid is looking immensely healthy, being a net exporter most days.

Will it handle an extended heatwave that also affects other states simultaneously? You’re right, we can’t know that with certainty until after it happens. But based on what I’ve read I’m confident it will.

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> It doesn't solve the problem- its the end of the day when solar has ramped down that the crises happens. Its the duck curve. Where its still hot and air conditioning is still running hard.

Isn't that scenario a problem only when the output from solar is insufficient to meet the aggregate demand?

From a naive point of view, it looks like this issue would be easily mitigated if supply from solar was increased enough to allow energy to be stored during peak hours so that it could be introduced back in the grid during sunset. Why is this scenario being ignored in a thread on how California is investing in battery energy storage?

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Knowing about the duck curve and taking advantage of the essentially zero marginal cost of solar, can't most folks just crank down their AC temps at 11 or noon such that there's no end-of-day demand ramp?

I know folks in Phoenix who are on a time-of-day plan and they max out the AC overnight and then barely use it during the day (same goal, just they don't have solar)

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This is indeed what I do when it's going to be very hot (105+) out.

I run the AC down to 64 overnight, and it's usually comfortable until well into the afternoon before it starts running at 73-74.

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I doesn't have to solve the problem.

It just has to help the problem.

Rooftop home solar+storage also doesn't have to SOLVE THE PROBLEM IN TOTALITY. It just has to help.

Energy is a cornucopia of solutions, which is a good thing. We aren't going to get everything from nuclear, it is far too expensive and can't function as a peaker (unless we had LFTR but oh well). Geothermal has a lot of potential, but it isn't perfect and probably investment heavy. Gas peaking is regrettable, but necessary currently. Solar and wind are by far the cheapest, but intermittent.

The goal should be stable, available, cheap energy. The path to that is solar + wind + battery + peaking + home solar/storage, but the grid monopolists aren't interested in cheap energy or the loss of control that home solar/storage comes with.

The fact that wind and solar are so cheap but grid prices are so expensive is an absolute SCANDAL.

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