Energy!

[deleted-146684]

I'm doing the project "Get Something for Nothing: Free Power from the Sun!" for my materials I will need a solar panel and investigate how varying the angle of the solar panel, and thus the amount of light it absorbs, affects the solar panel's output power. Before starting my experiment I want to know how is it that by moving the angle of my solar panel affects the amount of light it absorbs? Also, does it have to be really sunny in order for my experiment to work?

[rmarz]

esmeralda_31212 - A solar panel is most effective when it's angle is exactly perpendicular to the sun. You can almost model this mathematically (using trigonometry) by considering what effective area is being exposed to the light density of the sun. If you had a panel that was 4"x4" for example, if it were truly perpendicular to the sun it would receive 'X' light density over 16 square inches. If one axis was turned to an angle that was 45⁰ to the sun, the effective area presented to the sun would be one-half of the area or 0.5X radiation over the 16 square inches. It's like asking the question 'how big does my panel look as seen by the sun?'. There are some non-linear issues owing to the reflectivity of the panel, but those could be part of your experiment. Obviously a sunny day is better than a cloudy day, but the same principles apply to the efficiency of the panel.

Rick Marz