Solar power has been used since the beginning of time in one way or another but it is within the last century or so that it has become the source of efficient energy we see today. From the late 1800's solar power has been used to heat water for homes. In the United States solar powered water heating systems were used in California. After wonderful results, its popularity grew and solar powered water heating systems found their way to the Southwest region of the U.S. and in Florida. These systems were used in the United States until fossil fuel deposits were discovered in the west. Fossil fuels were abundant and cheap at the time and the use of solar powered water heating systems faded out of popularity during the 1930's.

There are a few different systems that are used to heat water. The batch system is one of the simplest and oldest. It is a tank in which water is housed and then directly heated by the sun. Another design uses a system of pumps to move the water around. The third system uses a natural circulation to move water.