Energetic and economic evaluation of photovoltaic cogeneration in Italy

Commercial photovoltaic modules have nowadays an efficiency around 12%-15%. It means that the most relevant part of solar radiation is lost. Such a remark gets more importance if the active surface is located in an urban environment, where the availability of surfaces exposed to the sun is scarce if compared to the buildings thermal loads. PhotoVoltaic / Thermal cogeneration (PV/T) aims to utilise the same area both for producing electricity and heat. The main problem of this technology is that solar cells are sensitive to temperatures and their efficiency lowers when temperature increases. Therefore heat cannot be collected at high temperatures. Nonetheless if the thermal part of the module is suitably designed to limiting the effect of the heat collection to the photovoltaic active layer, it can be feasible to contemporary produce heat at a suitable temperature and electricity. as it can be done by a bare panel. So for civil applications the electrical and thermal energy can be suitably used respectively to partially cover the needs for electricity and domestic hot water/space heating. So, some Italian climates and energy saving incentives scenario are taken into account with Trnsys simulations to evaluate the energetic and economic viability of the proposed PV/T technology.