Solar hot water panels are a means to harness the sun's energy in a unique way. Like traditional solar panels, solar hot water panels are placed in direct sunlight, oftentimes arrayed on rooftops. A solar hot water array, often referred to as a solar hot water heater, uses the energy from the sun to heat a fluid, which is in turn used to move heat generated in the array to a heat storage vessel. The process starts by heating a body of sanitized water and storing it in a hot water cylinder. Next, solar hot water panels would be installed on the rooftop, each with a darkly-coated absorber plate complete with water circulation tubes.

The tubes carray the heated water from the solar water heater to a place where it can be used or stored. A heat exchanger released heat and circulates the cooled water back to the solar hot water array to be reheated. This cycle of heating, energy utilization, and cooling is begun anew with each sunrise and lasts throughout the day for the effective life of the solar hot water heater. These arrays are especially useful for businesses that utilize large quantities of hot water, such as the pictured laudromat. Solar hot water heaters are composed of a several hot water panel units, and can be fully automated systems.