Analysis of the impact of thermal resistance of the roof on the performance of photovoltaic roof tiles

Poznan University of Technology, Faculty of Electrical Engineering, Institute of Electrical Engineering and Electronics, St. Piotrowo 3a, 60 – 965 Poznań, Poland

^⁎ Corresponding author: dariusz.kurz@put.poznan.pl

Abstract

The paper explores the issues related to the impact of thermal resistance of the roof on the electrical parameters of photovoltaic roof tiles. The methodology of determination of the thermal resistance and thermal transmittance factor was presented in accordance with the applicable legal regulations and standards. A test station was presented for the purpose of measurement of the parameters of photovoltaic roof tiles depending on the structure of the roof substrate. Detailed analysis of selected building components as well as their impact on the design thermal resistance factor and thermal transmittance factor was carried out. Results of our own studies, which indicated a relation between the type of the roof structure and the values of the electricity generated by photovoltaic tiles, were presented. Based on the calculations, it was concluded that the generated outputs in the respective constructions differ by maximum 6%. For cells with the highest temperature, the performance of the PV roof tiles on the respective roof constructions fell within the range between 0.4% and 1.2% (depending on the conducted measurement) and amounted to 8.76% (in reference to 9.97% for roof tiles with the lowest temperature).