Integrating Solar Heating and PV Cooling into the Building Envelope

Abstract

Photovoltaic/thermal (PVT) systems generate electrical and thermal energy. In summer, the usage of the collected heat is limited to domestic hot water heating. By contrast in winter, more useful heat collection is favorable, however, the PVT collectors require less cooling; therefore, the improved electrical output is limited. In this paper a new one-dimensional steady-state building integrated solar collector model is presented and examined, incorporating PVT and thermal (PVTT) collectors connected in series. In summer, the PVT collector is air-cooled, and the collected heat is discarded to the surroundings while the thermal collector heats the water for domestic use. In winter, both the PVT and thermal collectors are water-cooled generating domestic hot water. The efficiencies of the new collector are compared to that of a PVT collector, with both collectors having the same total area and characteristics. Both collectors are able to meet the summer thermal load and to provide useful thermal energy in winter. The PVTT collector reduces the collector thermal stresses and provides slight additional electrical power output.