Far Niente, a Napa Valley winery, paid quite a bit of money for the first floating solar farm. The 1000 (plus another 1300 panels next to the pond) panels are floating on pontoons and provide about 4000 kilowatts of energy at peak. Seems wineries are very eco-conscious, or have tons of money, or both. The PV system covers their annual electricity use.
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So what does this do to the water under these things? The plant life, fish life, and so on… Are they just hard up for space?