Solar Water Heaters are an efficient alternative to more traditional gas and electric powered water heaters. Water heaters powered by solar power (power collected by using the energy of sun light) provide heated water for homes.
The main component of a solar water heater is a solar collector and a storage unit. The solar collector is used to capture the energy of sun light is usually formed using dark color glazed box with a dark inside. The glazed material is usually glass, though it is not always. There are also cylindrical pathways filled with water that flows continuously to be heated by the energy created in the solar panel. This device uses the suns radiation and turns it into useable energy or heat. The storage unit holds the water to be heated and used.
Most solar water heaters work in this way, but they can fall into two categories: those which use some electricity to help move the water around via an electrical pump and those that use no electricity at all. This second type of heater uses only nature to help move the water around the unit.
A batch unit is a simple tank or tanks that hold water in a solar collector. The water is heated and gravity pushes the heated water inside the pipes of a home for use. A thermosiphon unit is a tank which stores the water after it has been heated in the tubes of the solar collector. Then the water is pushed into the pipes of the home through natural convection.
Some units are not totally solar powered. These use a small amount of electricity to move the water through the heater using an electric pump. Some of these units actually have two sets of cylinders inside the units. One set for the water to be heated and one set for a heat transfer liquid such as distilled water or antifreeze. In this case, the heat is transferred from the transfer liquid to the water to be used in the home. One type called a “drainback” unit actually has an interior storage tank to keep the liquid from being exposed to the elements. The transfer liquid drains back into a separate storage unit.
Solar water heating systems are more costly to purchase in most cases than a gas or electric water heater. These systems are an economical choice because they use little or no electricity. This choice is also more environmentally friendly than gas or electric.