Performance of a dielectric PVT concentrator for building-façade integration.

Concentrating photovoltaic-thermal (CPVT) systems, which can be integrated on buildings façades and use low-accuracy trackers and standard cells, have the potential to produce cost-effective electricity and heat. In this paper, a refractive cylindrical CPVT module with cells directly immersed in deionized water (DIW) or isopropyl alcohol (IPA) is designed, fabricated and experimentally tested. The interfaces between the cylinder and the fluids cavity have been optimized to maximize optical efficiency and irradiance uniformity, obtaining better results for a geometric concentration of 10x and IPA. The system achieves an optical efficiency of 81%, an acceptance angle of 1.07° and a non-uniformity coefficient of 0.13.