Sun catchers

Solar Collectors collect solar radiation from the sun. The solar collectors use this radiation for solar heating and for the heating of water. Generally mounted on roofs, these devices have to be very sturdy to endure different weather conditions.

Solar Collectors are meant to be as effective as possible. It consists of a glass plate on top, then a copper-tube below the glass, and a black metal plate behind the tube. The metal plate absorbs the heat and makes and prevents heat-loss. The glass plate lets the sunlight through to the metal plate, and reduces heat-loss in the surrounding area as well. Water goes through the copper tube. Cold water goes in on one side, and while passing over the hot metal plate it heats up, before coming out as hot water on the other side.

These solar collectors are connected to a energy storage within the house. The water circulates in the house so that the warm water gets moved to the energy storage.

Efficiency of a Solar Collector

A solar collector with an area of one meter squared would receive 300 W/m^2 from the sun. This is the power supplied. It delivers 220 W. This is the useful effect. To find the efficiency we divide the useful effect over the power supplied, and we get 73%. This means that solar collectors converts 73% of the solar radiation it receives