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Name: Vitor Manuel Paix√£o
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i'm trying to calculate the inclination angle of a solar panel. I know it is usually in N-S orientation with a tilt equal to the latitude of the place, but i would like to know why

If a solar panel is tilted so that it faces south ande its angle from the horizontal is equal to the latitude of the place where it is located, it will catch the most light from the sun. This is because the sun's average angle in the sky is equal to the latitude of where you are looking at it: at the equator, the sun appears to cut right through the middle of the sky; farther north, the sun is in the south. In the Summer, the sun will be farther north than average; in the winter, it will be farther south.

Of course, the Sun doesn't really move; it's the earth rotating on its axis and orbiting around the Sun that causes these effects. If the earth's axis weren't tilted with respect to the plane of its orbit, there would be no difference between Summer and Winter.

Richard E Barrans

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