This shows how to install tankless booster heaters to supplement a solar water heating system with a hot water storage tank. One recirculation pump is used to circulate the water between the storage tank and the solar panels. Another recirc pump could be used to circulate the water between the storage tank and the building outlets. Instantaneous water heaters can be used to help boost the water temperature or as supplemental water heating in the case that the solar heating system cannot keep up with the demand.