Previous clean energy investments by Google include eSolar Inc, which builds Concentrating Solar Power (CSP) plants, as well as AltaRock Energy and Potter Drilling, which use various techniques to optimize and develop geothermal energy sources.

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Utility-scale concentrating solar power (CSP) systems that produce electricity using lenses or mirrors to focus radiation on thermal collectors or photovoltaic cells draw criticism from environmental groups for taking up too much desert land, thus displacing certain animal and reptile species.

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They argue solar thermal (also called concentrating solar power, or CSP) is getting cheaper fast, too, because of new, more efficient technologies.

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While the low water use and cost of PV will appeal in the desert kingdom, the fact that solar will be displacing power generated from oil means that even CSP based power will produce cost reductions.

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This might make sense for large scale solar farms, since the integration of PV would allow the overall price of power to be lower than CSP alone, while CSP would be able to compensate for the rapid output changes from PV that occur whenever a cloud passes over, as well as producing power at night, or shifting it ot peak afternoon periods.

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