Active Solar Heating
Active solar heating main purpose is to use the solar cells to collect and absorb solar radiation. The radiation is converted into heat by solar cells and then its transferred to the interior of the building. Active solar heating works in two ways.
First way is through solar liquid heating. Solar heating usually warms water or antifreeze through the use of solar cells. Then the liquid is pumped into home and heats it via radiators. In some cases same method is used to heat pools.
Second method of active solar heating is solar air heating. Solar panels warm the air then that air is pumped into home through a forced air pump. Active solar heating systems are usually designed in such that that they meet 40 to 80 percent of a home’s heating needs, as less than 40 percent is not cost effective and more than 80 percent usually requires the use of too many solar cells.
Passive Solar Heating
Warming the building by using natural sunlight is called Passive Solar heating. Homes that use passive solar heating usually have large windows facing southwards. The home which use passive solar heating they are well insulated and often have overhangs over the windows to keep the home cool when sun is at its highest. Passive solar homes also take advantage of insulated curtains and windows to minimize heat loss.
Solar Electric System
To absorb solar radiation a solar electric system uses photovoltaic cells. These photovoltaic cells are semiconductors. Electrons are loose out when the cells absorb sunlight this is called photoelectric effect. Then free electrons move to circuit where they form an electrical current. Cells are connected to form panels and each panel creates 10 to 300 watts. Usually a building or home haves several panels for its power supply. The panels are fixed in a specific angle, or panels are having tracking device to maximize power for a day. Solar panels can stand-alone or can be hooked up to the power grid. There several solar array systems in the southwest that supply the electric grid.