A solar thermal system consists of two main components; a solar collector and a hot water storage tank.
The solar collector, located on the roof, collects the suns energy and transfers the heat to the storage tank. The storage tank allows the hot water to be stored until it is used at night or in the morning.
If the storage tank (geyser) can be mounted higher than the solar collector, the rising of the hot water can cause the transfer of the heat from the collector to the tank. This is called a thermosiphon system. If the storage tank is mounted lower than the solar collector a circulation pump and differential temperature controllers is required. This is called a pumped system.