Comment by anovikov | Hacker News Reader

Comment by anovikov | Hacker News Reader

Question must be, what's the point of uber large storage sites? Storage is essential, but where is the economy of scale of large sites, how are they more economic than small - say container-sized, a ~1 MWh - ones? Having smaller systems, closer to producer, must also save on transmission capacity, no? Not to mention, given the geopolitical situation, their safety.

I'm also convinced that separating generation and storage is simply an awfully, comically bad idea: generation that needs storage - solar and wind - is DC, storage is also DC. Transmission is usually AC or at least goes through AC/DC conversion at some point.

Why wasting a lot of additional energy to store it by doing an extra unneeded AC/DC conversion which happens if storage is separate from generation? Instead of storing DC energy as it is produced and discharging it - by converting to AC and feeding into the grid - as it is needed?

My uneducated guess would be shared power infrastructure, easier licensing and permitting for one site, one large safety/fire extinguishment system instead of many, etc. The article mentions only 2 transformers needed to link that entire station to the grid. Also the controls, managing power delivery from thousands of small batteries versus one centralized facility. And if that particular wind or solar project doesn't go well for some reason the battery isn't tied to it, it's stabilizing the overall grid. Not sure though it is a good question, probably some technical or regulatory docs that go into details somewhere, I'd imagine this would have a ton of bureaucracy before getting built

I think your assumptions about transmission losses are wrong.

Transmission losses are on the order of a couple percent. Most of these large sites are literally composed of 1-2 mwh containerized units side by side.

Transmission losses are not high, but AC/DC conversion losses are significant. Whenever there's a chance to avoid an extra conversion it's inefficient to miss it.

While as other commenter said, this is only pertinent to solar, not to wind.

Speaking of saving on transmission capacity i didn't mean "limiting transmission losses" but "avoiding hitting the limit of transmission power lines because the power will travel a shorter distance between the producer and the battery".

This might be a small site by the time the planet is converted.

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