How practical is solar power for various devices?
Assume that on a sunny day, sunlight has an intensity of 1000 W/m2 at the surface of Earth and that, when illuminated by that sunlight, a solar-cell panel can convert 10% of the sunlight’s energy into electric power. For each device given below, calculate the area A of solar panel needed to power it. (a) A calculator consumes 50 mW. Find A in cm2. Is A small enough so that the solar panel can be mounted directly on the calculator that it is powering? (b) A hair dryer consumes 1500 W. Find A in m2. Assuming no other electronic devices are operating within a house at the same time, is A small enough so that the hair dryer can be powered by a solar panel mounted on the house’s roof? (c) A car requires 20 hp for highway driving at constant velocity (this car would perform poorly in situations requiring acceleration). Find A in m2. Is A small enough so that this solar panel can he mounted directly on the car and power it in “real time”?
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