In this study, a new solar photovoltaic (PV) panel output power model is proposed. The model is constructed as a function of ambient temperature and solar radiations for two types (fixed panel and sun tracking panel) of PV systems. The proposed models are tested and verified on the Renewable Energy Research Home (RERH) system that was installed at the Anadolu University campus in Eskişehir, Turkey. The model is deliberately constructed for the winter season, where cloudliness, rain and snow constitute more challenging conditions for modeling. The developed model outcomes are compared to the outputs of state of the art methods that use global solar radiation and temperature data. A total of eight algebraic models are constructed for the purpose of depicting the solar radiation-to-electric power behavior. It is observed that even the least successful one of these eight variants are performing better than the most accurate method in the literature. It is argued that mathematical incorporation of the proposed novel hysteresis functions to the solar radiation-to-power conversion curves results in a richer class of functions and causes a significant accuracy improvement on the mathematical power generation model, even for the most challenging season of winter.

In this study, efficiency analysis of the tracking solar photovoltaic (PV) system in Eskişehir region is considered for onsite real solar power generation values. It is shown that the tracking system’s power generations are always higher than fixed one, but increased yield ratio is changing according to weather conditions (sunny or cloudy times). In order to make a fair analysis/comparison, all the instantaneous real solar power generations between 1 July and 30 October 2016 are used to figure out the ratio of sunny and cloudy days of whole year. The averaged total generation values are calculated and it is revealed that tracking system provides approximately 33 % higher yield from same capacity fixed PV panels for Eskişehir region.