- #1

lavinia

Science Advisor

Gold Member

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For instance, if we imagine that the entire surface area of the Earth were covered with deserts and no cloud ever appeared in the sky and then computed the rate of sunlight energy hitting the planet that would seem to be way above any realistic bound on the amount of usable solar energy per unit time. There must be some reasonable calculations that allow for a relatively small usable surface area and for normal weather conditions and for an upper bound on the efficiency of possible solar collectors.