Dynamic simulation, energy and economic comparison between BIPV and BIPVT collectors coupled with micro-wind turbines

The work presents a dynamic simulation and an energy and economic analysis of two different Building Integrated Solar Technologies, namely: Building Integrated PhotoVoltaic (BIPV) collectors and Building Integrated hybrid PhotoVoltaic-Thermal (BIPVT) collectors. Both systems are coupled with small size Wind Turbines (WTs), to reduce the fluctuations of power production typical of solar systems. A case study is presented, referred to a hotel building, where a reversible air-to-water Heat Pump (HP) is used for space heating and cooling, driven by the electric energy provided by PV collectors and WTs. In order to optimize the HP performance in cooling mode, thermal energy is recovered from the HP desuperheater and used to produce domestic hot water (DHW). A two-stage cascade cycle HP for DHW purposes was also investigated, as a further alternative. The systems were simulated by means of a dynamic simulation model, developed in TRNSYS. The results show that the BIPV-based system is more profitable than the BIPVT one, achieving a simple payback period of about 4.5 years; for both systems, the optimum size of the WT system, for a given area of PV collectors, was also investigated.