Heat energy from the sun
Every one of us has heard about the heat produced by the sun and how harnessing it can yield amazing results for us as well as for the ecosystem. Majorly the thermal energy harnessed from the sun is used in hearting up of water, may be in a swimming pool or water heated for domestic use. Maximum use of the energy is done by using the flat plate solar converters which have a fixed position.At places where the space heating is of maximum priority, the maximum benefit is derived if the flat plate collector is placed at an angle equal to the latitude plus approximately 15 degrees in the south direction.
The two categories that we will mainly come across in a solar converter is
1) concentrating
2) nonconcentrating.
In the concentrating type solar heater, the area exposed to the solar radiation that is interception area, that collect the radiating is huge, sometimes hundreds of times, than the area that absorbs the energy or the absorber.
In the nonconcentrating type of heaters, the two areas i.e. the absorber and the interception area is the same.
For temperatures below 200 degree F, nonconcentrating type of heaters are sufficient.
The typical flat plate solar heater design consists of
1) an absorber which absorbs and intercepts solar heat,
2) a transparent film which works as a heat retainer, but does not prevent the sun light to pass through to the absorber,
3) a fluid to transport heat, which may be water or air, which flowes through the tubes and removes heat from the absorber
4) a backing of heat insulation.
Thermal heating systems can be classified into active or passive systems.
Passive systems are the ones where air is circulated along a solar heat surface and then through the building by way of convection, while in active systems air is pumped by fans and pumps.
