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I'm not sure about any of these plants in particular, but a lot don't use PV cells, instead using mirrors to heat and evaporate a liquid, driving a turbine.



I don't know whether it's accurate, but I've noticed people saying that these sorts of plants are kind of obsolete these days, because of the development of PV cells.


It's actually liquid sodium in newer designs, which retains heat well, is stored in an insulated tank, and can generate power using that heat even after the sun goes down. So no, I don't think they're obsolete. https://www.scientificamerican.com/article/new-concentrating...


Want to know something else that is fun about the concentrated thermal projects? If the sun is not available for long periods of time and the fluid cools down too much they have to dump energy into it to prevent it from solidify to point of overwhelming the pumps capacity!


Sounds like a good reason to keep that kind of generation in the desert, then. That's interesting, though. I suppose they could just divert some power generation to battery storage for those heaters though, just like nuclear reactors have backup generators for cooling.


FYI, liquid salt is not quite the same thing as liquid sodium. Source: someone I knew worked on liquid sodium power plants.

Also, I think PV prices may have declined around 50% since that article was written.


Not necessarily obsolete, just uncompetitive. Many of the concentrated thermal systems can meet 30% efficiency but they usually are more of steel and plumbing projects than solar projects. On top of the high initial capital cost, they have higher maintenance as it is a system of high temperatures with moving parts.


That was exactly the meaning/claim - that because PV prices have fallen, it doesn't make sense to build new thermal plants.


They're all very, very publicly documented - just google it!




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