The main type of solar heaters function by employing solar energy collectors mounted on a solar panel. These collectors absorb solar energy when they are struck by light from the sun, and this energy is used to operate the heater. As solar powered heaters rely on solar energy to function, they obviously cannot operate when the sun has gone down, but many solar heaters are fitted with systems that power down the heater when the level of light drops below a predetermined level.
Solar Water Heater
There are two main categories of solar heating system. The first of these, and most common, is called a solar water heater, also known as a solar hot water heater. These heating systems are used to produce hot water for a home or business in a relatively low-cost and environmentally friendly manner. They work by pumping cold water from an internal tank through the solar collectors, which will have been heating by the sun. This process heats the water as it passes through the solar collectors and it is then transferred to a heated storage tank, where it remains until it is needed. Once the heated water is in the storage tank, a valve closes over the top to ensure the minimum amount of heat is lost. If the storage tank is particularly large, it is possible to go for extended periods of time without reheating the water that is being stored. Solar water heaters of this kind are often designed to cease operation of the water pump when the sun goes down, which automatically closes the lid of the storage tank. This ensures that the water within can remain heated overnight, and be used for any desired domestic function. Although mostly self-powered, solar heaters often have an auxiliary power source such as gas or electricity. This auxiliary power source may be used to pre-heat the water storage tank in particularly cold environments, which although a useful feature, does increase the environmental impact of the solar heater slightly.
Solar Air Heater
The other main type of solar-powered heater is a solar air heater. Solar air heaters function by collecting energy from the sun using solar collectors, in the same way as a solar water heater. The difference in their design lies in the fact that instead of heating water, they heat air that is pumped through the collectors, or in simpler models passes through the collectors by convection. This heated air is then passed though ventilation conduits throughout the property where the solar heater is located. The spread of the heated air is sometimes helped by use of a fan system, but this requires more power and makes the system less self-contained.
Solar heaters are an attractive prospect for those who value systems with a low environmental impact, as solar energy is free and available daily, weather permitting. Solar greenhouse heaters and solar pool heaters are available for domestic and commercial use, and work on either of the two principles described above. Fitting a solar pool heater can be a simple DIY procedure and a cost-effective way of heating a pool quickly and easily. Solar powered heaters are often employed by businesses who strive to be environmentally conscious, and the easily expandable nature of solar panelling allows the system to be fitted to buildings of almost any size.