Energy performance of photovoltaic (PV) windows under typical climates of China in terms of transmittance and orientation

PV windows provide thermal insulation, daylight use and power generation simultaneously. Present investigation aimed to evaluate the energy performance of 3 types of PV windows under 5 climates of China, and particularly to clarify the influences of transmittance and orientation on its energy performance. The present work involves: (i)the experimental testing that had been carried out; (ii)validation of the EnergyPlus model of natural ventilated double PV (NVDPV) window; (iii) prediction of the energy performance of the 5 PV windows under typical climates of China based on the validated model; (iv) applicability discussion of the PV windows under different climates and influence of transmittance and orientation. The results reveal the highest energy saving rate obtained by NVDPV window in the 5 cities. The NVDPV window integrated PV glass with transmittance of 10% delivered better energy performance than the window with transmittance of 5% under climates of Harbin, Beijing, Shanghai and Shenzhen. The south facing windows achieved least building electricity consumption under the climates of Harbin, Beijing, Shanghai, and Lhasa. Exceptionally, the east facing windows achieved least electricity usage under the climate of Shenzhen. The achievements from the present work provide a reliable criterion for the optimized design of PV windows.