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Solar Heating

Solar Heating describes the process whereby the sun's enery is used to heat water directly. If you imagine a tin can full of water sitting out in the desert, this would be a crude form of solar heating. Solar heating for domestic use is a bit more sophisticated, of course.

In a home solar power system, solar heating provides hot water by using the sun to heat it directly. A typical system consists of one or more thermal collectors or solar collectors usually mounted on the roof and a hot water cylinder with two coils. One coil is heated by the boiler as usual and the other coil is connected to the solar connectors on the roof via a pump.

Note that because a hot water cyclinder is needed, solar heating is not normally suitable for use with a conventional combination (combi) boiler system. It is possible to use solar heating with a combi boiler if an additional storage tank is used. Water in the storage tank is heated by the solar collector as usual and the storage tank feeds the combi boiler. The water feeding the combi boiler is therefore pre-heated and the combi will only fire up if it is necessary to 'top up' the heat.

Depending on the type, solar collectors can be mounted on the roof, the gable end of a building or even on a purpose built frame. The important thing to consider is location. The maximum efficiency of the collector is achieved when it is positioned within 45 degrees of south.

Solar Heating Options

For a home solar power, solar heating system, two types of solar collector are available: Vacuum tube and Flat Plate.

Vacuum Tube

Vacuum Tube solar collectors are more efficient than the flat plate variety. Inside the collector is a series of evacuated tubes which connect to a manifold with a heat transfer fluid flowing through it. Vacuum Tube collectors can only be mounted on the roof.

Flat Plate

These are less efficient than vacuum tube collectors. They consist of a collector containing a series of antifreeze filled pipes. Flat Plate collectors can be bolted onto the roof or integrated in the roof.

Finally...

Don't forget about insulation. There is little point in installing a state of the art home solar power system if your heating system, and that means every bit of your heating system, is not properly insulated. Correctly designed and installed it should be possible to achieve efficiencies in excess of 60% from your home solar power solar heating system.