Using solar hot water systems can be a reliable way of heating water while still maintaining an energy-efficient lifestyle. There are several different types of solar hot water devices, depending upon the particular needs of a household. Active solar hot water systems, which use a pump to move water around the system, have two different modes: direct and indirect circulation systems.
Indirect Circulation Systems
Indirect circulation systems using a heat-transferring fluid to move warmth from the solar collector to the solar hot water exchanger. The exchanger then transfers heat from the fluid to the water waiting in the storage tank. This process is much simpler and quicker than it sounds.
Indirect circulation systems can also use non-freezing fluid in areas where the weather can get chilly. This ensures that the liquid within the solar hot water system is constantly mobile. The indirect circulation system is more regularly used in the North, where the climate can often drop below freezing.
Indirect circulation solar hot water systems are considered to be more expensive than their direct circulation cousins, due to their added mechanisms, and the increased likelihood of heat loss during transfer. Indirect circulation is perhaps less commercially viable than direct versions, although it may be of more practical use in higher latitudes and in colder regions.