Solar (photovoltaic) Panels

Photovoltaic (PV) panels convert solar energy (light) into electrical energy (electricity). They accoplish this by channeling free electrons ( freed by light striking the panel surface ) into a current path that eventually leads to the output wires of the solar panel. Modern solar panels convert light to electricity with about 5% to 15% efficiency, with most of the light being relected or absorbed in the form of heat.
Made up of a series of individual solar cells, solar panels come in many sizes and configurations. Most panels in the home power industry range from 20 - 120 watts power output in full sun. When operated in shaded or overcast conditions, power output will drop drastically. Even shading one cell can reduce the power output of a solar panel to a "shadow" of it's former self, with different brands and configurations of panels being more or less affected depending on design.
For best performance, solar panels should be mounted in such a way that the surface of the panel will be more or less perpendicular to the sun's rays, either on a fixed or sun tracking mounting structure. The mounting area should be free of obstructions that could even partially shade the panels, and they should be effectively secured to prevent shifting under any expected condition.