Evaluation of proposed photovoltaic energy rating standard: validation against outdoor measurements

Effective energy production is the ultimate purpose of photovoltaic devices and thus should be considered in describing device performance. This paper investigates the impact and relevance of the proposed IEC energy rating standard reference days on the energy prediction of various device technologies in the UK climate and found MIMT and MIHT are most relevant. Three different module technologies have been tested over a wide range of module temperature (Tmod) and irradiance (G) level in outdoor measurement conditions. Performance of each technology is calculated in terms of distribution of energy generation with the main influencing parameters. The paper also compares the power distributions (with irradiance and temperature) of crystalline silicon modules in indoor and outdoor measurement conditions. Sensitivity analysis of energy yield estimation and its modelling accuracy are analysed for three devices with the different combinations of Gmod and Tmod and its found that c-Si and a-Si device technologies underestimated by 7.6% and 6.8% but CIGS module overestimated by 0.05% in the UK climate.