Effects of light, heat and relative humidity on the accelerated testing of photovoltaic degradation using Arrhenius model

Energy demands in Nigeria has increased tremendously over the past decade due to the increasing levels of industrialization and population size. This has led to a higher reliance on solar photovoltaic (PV) modules for power generation since Nigeria receives abundant solar energy. However, no information exists on the lifetime and reliability of PV modules operating in the Nigerian climate. The information on how long PV modules will last when operated in the Nigerian weather becomes necessary since many private and Government parastatals are heavily investing in installing and relying on PV generated electricity. The objective of this study is to compute the acceleration factor and effective temperatures in different strategic locations in Nigeria by considering the combined effects of light, heat and irradiation. The analysis is conducted for different PV module configurations (glass-cell-polymer) and (glass-cell-glass) using the Arrhenius model. A 13-year (2005–2017) climatic data of seven strategic locations that encompass the six climatic zones in Nigeria including the National Capital was used. Results are that when relative humidity was neglected, the acceleration factors for the seven states ranged from 1 to 4. However, when relative humidity was considered, Northern states with relative humidity of about 50% had the highest acceleration factors of up to 50, while other regions with relative humidity above 80% had peak acceleration factors of about 14. The results obtained from this study should provide useful guidelines on the lifespan testing of PV modules operating in Nigeria as a case study and other geographical regions as well.