[paulyg]

Why are people comparing and debating "batteries vs combustion turbines"? Batteries only store energy and you still need to generate it somewhere. Probably from a CCGT plant.

And it's not risk aversion. Its buried subtly in the article but part of SoCal's gas infrastructure is shut down because of the leak. They literally can't provide enough gas to generate enough electricity for peak demand. So they will generate over capacity at night, store in the batteries, and discharge during the day.

Also what seems to be lost here is that Tesla created it's utility battery products as a renewables play, but are just taking advantage of extra-ordinary circumstances in this case.

[mikeash]

People are comparing them because they serve the same purpose here.

Base and peak loads on the grid can be wildly different. Without storage, if you want to avoid brownouts or blackouts, your generating capacity needs to match the peak load, even though you might only hit peak load a few times per year. The traditional way to handle this is to have power plants that can be spun up rapidly but sit idle 99% of the time. Because they're idle most of the time, the electricity they produce is extremely expensive.

Storage (including batteries, but also many other technologies) can substitute for these plants. You fill the storage when demand is low, then drain it when demand is high. Yes, the energy still needs to be generated somewhere, but you can generate it using existing plants during periods of low demand. If this is cheaper than maintaining peaking plants that mostly sit idle, it's a win.

[paulyg]

Yes I know how all that works becuase I worked in the utility industry for over a decade.

My point was (1) when comparing peakers vs storage you need to consider the cost of: Off-peak generation + storage cost vs peaker cost. (2) This wasn't a cost driven thing. This is a demand driven thing.

[garretraziel]

Or you can use PHS: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...

[amelius]

Energy density of gas (at conventional pressure) is 100x lower than that of a charged battery. Storing gas instead of electricity might not be such a good option.

Otoh, a gas tank requires only O(E^(2/3)) material, while a battery requires O(E) material, where E = stored energy.