Bivalent Water Heating System

摘要

A bivalent water-heating system includes a water-storage tank having at least one wall defining an interior storage cavity configured for storing water to be heated. The storage cavity includes an upper-cavity and lower-cavity portions. A non-solar heating unit is situated at least partially in the upper-cavity portion and includes a combustion chamber defined by at least one wall through which heat produced by the combustion of fuel is transferred to stored water located within the upper-cavity portion. Water stored in the lower-cavity portion is heated by a solar heating subsystem that circulates a heat-transferring fluid between a solar collector that converts solar radiation to heat energy and a heat exchanger situated within the lower-cavity portion such that heat-transferring fluid (i) absorbs heat at the solar collector, (ii) is routed to the heat exchanger where the heat-transferring fluid transfers heat to water stored in the lower-cavity portion, and (iii) is returned from the heat exchanger to the solar collector to absorb additional heat.