Luckily for the Earth the future of Solar Thermal Energy is very bright. In the current state of the world’s energy crisis, new uses for solar energy are being developed. The positive aspect of solar energy is the fact that it is completely renewable. It can be used for heating purposes of many sorts, with the use of small, medium, or large solar collectors.
Thermal solar collectors are more efficient than photovoltaic solar collectors because of the lower cost it takes to collect the solar energy. Photovoltaic plants are becoming more common, but have huge startup costs. Solar thermal collectors instead use natural heat collectors such as stone. The thermal energy is concentrated with the use of mirrors or lenses (in the form of a reflector dish) to concentrate the sunlight into a small area. This concentrated sunlight is then transferred to heat fluid inside an absorber tube. This is then transferred to a heat engine, which can convert the heat into electricity.
Solar Thermal Energy has several additional advantages. The heat can be stored in insulated reservoirs and then used later. Thermal plants can even produce power at night and on overcast days. Thermal energy can also be used to desalinate water, which will be very useful in coastal areas.
The technology is simple, reliable and needed! It is estimated that solar thermal could provide all of the power requirements of the United States. This could be accomplished with the use of a 92 by 92 mile grid of solar thermal generators. This might be a large area but considering the amount of land that is available, and the benefit it will have for society, it is certainly a viable option.
There are three types of solar energy heat collectors and all are used in conventional systems. Low temperature collectors are flat plates that are most often used to heat swimming pools. Medium temperature collectors are also flat plates, but are used for creating hot water for residential and commercial use. High temperature collectors are not in plate form, but instead use mirrors and lenses. They can be used for some electric power production.
Low temperature collection is used for heating, cooling, ventilation, and processing heat. Heating, ventilation, and air conditioning account for 25 percent to 50 percent of the energy used in residential and commercial buildings. This can be offset with thermal energy. This thermal technology stores solar energy during the day and then releases it in the evening or whenever the temperature lowers. The most common thermal mass materials include stone, concrete, and water. Thermal energy is used in this case as a passive system which maintains comfortable temperatures through the slow release of energy.
Medium temperature collectors are most used for cooking. The solar cookers are used for cooking, drying, and pasteurization. This sort of thermal energy use diminishes air pollution, as well as reduces the use of fuel and firewood.
High temperature collectors are used primarily for space heating, using fluid-filled pipes. This is still not used for large scale conversion to electricity as the temperatures are still too low.