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It would require about 31 hectares of corn ethanol to produce the same amount of energy generated by 1 ha of solar panels
(www.anthropocenemagazine.org)
Everything about energy production and storage.
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4,000MW / 400w per panel = 10,000,000 panels, or about 3,444 acres of solar panels. That's about the size of a small-ish town, and 75x larger than an equivalently rated nuclear plant.
However, the initial and maintenance costs of so many solar panels are far lower than those of nuclear, or at least they were before Orange Monday.