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Your concerns are interesting.

Here are some solar power plants that appear to have the secret to overcoming temperature, sand, and wind. Any ideas what they're doing?

• 1547 MW capacity: Tengger Desert Solar Park

• 1000 MW capacity: Kurnool Ultra Mega Solar Park

• 1000 MW capacity: Datong Solar Power Top Runner Base

• 850 MW capacity: Longyangxia Dam Solar Park

• 746 MW capacity: Bhadla Solar Park

• 600 MW capacity: Pavagada Solar Park

• 579 MW capacity: Solar Star, Rosamond, CA, United States

• 552 MW capacity: Copper Mountain Solar Facility, Boulder City, NV, United States

• 550 MW capacity: Topaz Solar Farm, San Luis Obispo County, CA, United States

• 550 MW capacity: Desert Sunlight, Desert Center, CA, United States

• 500 MW capacity: Huanghe Hydropower Golmud Solar Park

• 452 MW capacity: Mount Signal Solar, Calexico, CA, United States

• 400 MW capacity: Mesquite Solar Project, Arlington, AZ, United States

• 140 W capacity: Mars Spirit Rover (ok, the experiment failed in 2011)

• 140 W capacity: Mars Opportunity Rover




All PV cells have a temperature coefficient that reduces their productivity in heat. some preform better than others. Thin-film is notable example. Placing large PV farms in the desert is mainly about two things: High insolation value and cheap land that is easy to build on. Many of the desert regions have very few cloudy days each year offering more available sunlight hours improving the annual production of the system. Second, land in the desert regions are orders of magnitude cheaper to buy than other areas. This drives down overall project cost and improves the IRR. In addition to the land being cheap, it hold little economic value for much else. If it can be used for generating power, then local authorities are often favorable when reviewing these projects.


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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