Theoretical study on thermoelectric performance and building energy efficiency of solar CPC concentrating building roofs

Presents a CPC concentrating photovoltaic system with rain-water collecting function coupled with buildings. The system mainly includes the water collection tank, CPC, photovoltaic panel and rectangular aluminum tube, etc. Uses the water collection tank to replenish water on rainy days and release water on sunny days. The CPC and photovoltaic panel are placed on the roof surface to efficiently generate electricity while avoiding the increase of indoor cooling load caused by direct sunlight radiation. The hollow aluminum substrate on the back of the photovoltaic panel is embedded in the roof of the building, which is filled with collected rain-water to effectively take away the photovoltaic residual heat. Analyses the effects of cooling water flow velocity and temperature and focusing multiple on the performance of CPC concentrating water cooling system, the effects of outdoor air velocity and irradiance on the performance of three different forms of photovoltaic cells, and the economy of the system. The system not only reduces the building heat gain caused by direct sunlight on the roof surface and the indoor cooling load, but also collects rain-water and generates high grade electric energy, which realizing the high-level coupling with the building and the comprehensive utilization of photoelectricity and photothermal, effectively reducing the building energy consumption.