The solar heating system consists of the solar collector; a heat transfer circuit that includes the fluid and the means to circulate it; and a storage system including a heat exchanger (if the fluid circulating through the collector is not the same liquid being used to heat the object of the system). The system may or may not include secondary distribution of heat among different storage reservoirs or users of the heat. The system can be used in a variety of ways, including warming domestic hot water, heating swimming pools, heating water for a radiator or floor-coil heating circuit, heating an industrial dryer, or providing input energy for a cooling system, among others. The heat is normally stored in insulated storage tanks full of water. Heat storage is usually intended to cover a day or two's requirements, but other concepts exist including (where summer solar energy is used for winter heating by just raising the temperature by a few degrees of several million litres of water