ABSTRACT

A photovoltaic/thermal (PVT) hybrid solar system is a combination of photovoltaic (PV) and solar thermal components/systems which produce both electricity and heat from one integrated component or system. A significant amount of research and development work on the PVT technology has been conducted in the last 35 years with a gradual increase in the level of activities. There appears a wider scope of international participations after the turn of the century. A solar cell has its threshold photon energy corresponding to the particular energy band gap below which electricity conversion does not take place. Photons of longer wavelength do not generate electron–hole pairs but only dissipate their energy as heat in the cell. The increase in PVT research in the 1990s apparently had been a response to the global environmental deterioration and the growing interest of the construction industry towards the building-integrated photovoltaic options.