Solar water heating systems, or 'solar thermal' systems, use free heat from the sun to warm hot water.

This replaces other energy sources such as natural gas and electricity as a means of providing hot water to buildings. A conventional boiler or immersion heater can be used to make the water hotter, or to provide hot water when solar energy is unavailable.

Did you know? A well designed solar thermal system can provide 40% of domestic hot water Figure. The most important part of a solar thermal system is the ‘collector’. The collector’s role is to absorb the sun’s energy and efficiently convert it to heat for transfer to the hot water system. The collector is normally mounted on the roof of a building.

Hot water is supplied to the building by transferring the heat (energy) absorbed by the collector and pumping it down to the cylinder tank. The solar energy reduces the heat demand on the boiler, and therefore energy consumption and cost.

Solar water heating systems, or solar thermal systems, use energy from the sun to warm water for storage in a hot water cylinder or thermal store. Because the amount of available solar energy varies throughout the year, a solar water heating system won’t provide 100% of the hot water required throughout the year. A conventional boiler or immersion heater is normally used to make up the difference.