Performance Assessment of a Photovoltaic-Thermal Roof with Modular Heat Exchanger
Abstract
The paper presents the thermal performance of a novel photovoltaic-thermal (PV/T) system conceived for roof integration. Main feature of the system is the modular assembly of the metallic heat exchanger, which also serves as self-supporting mounting device for the photovoltaic modules and assumes a static function. The design of the heat exchanger has been optimized by using numerical FEM simulations in order to fulfill both energetic and economic requirements. We investigate the performance of the system by means of long-term measurements on a large-sized PV/T roof prototype equipped with thin film CdTe photovoltaic modules under real weather conditions and at different operation conditions. The evaluation has been carried out according to the Standard ISO 9806 and focusing on the quasi-dynamic test method. The experimental results (η0, MPP = 0.66; a1 = 11.56 W/m²K; a2 = 0.09 W/m²K²; a3 = 1.26 J/(m3K), a6 = 0.03 s/m) prove the efficient heat transfer from the absorber to the fluid and are in good agreement with the simulations.