The impacts of climate change on photovoltaic (PV) output in the fifteen countries of the Economic Community of West African States (ECOWAS) was analyzed in this paper. Using a set of eight climate models, the trends of solar radiation and temperature between 2006–2100 were examined. Assuming a lifetime of 40 years, the future changes of photovoltaic energy output for the tilted plane receptor compared to 2006–2015 were computed for the whole region. The results show that the trendsof solar irradiation are negative except for the Irish Centre for High-End Computing model whichpredicts a positive trend with a maximum value of 0.17 W/m²/year for Cape Verde and the minimumof −0.06 W/m²/year for Liberia. The minimum of the negative trend is −0.18 W/m²/year predictedby the Model for Interdisciplinary Research on Climate (MIROC), developed at the University of Tokyo Center for Climate System Research for Cape Verde. Furthermore, temperature trendsare positive with a maximum of 0.08 K/yearpredicted by MIROC for Niger and minimum of0.03 K/year predicted by Nature Conservancy of Canada (NCC), Max Planck Institute (MPI) forClimate Meteorology at Hamburg, French National Meteorological Research Center (CNRM) andCanadian Centre for Climate Modelling and Analysis (CCCMA) for Cape Verde. Photovolataic
energy output changes show increasing trends in Sierra Leone with 0.013%/year as the maximum. Climate change will lead to a decreasing trend of PV output in the rest of the countries with aminimum of 0.032%/year in Niger.

climate model; solar radiation; ambient air temperature changes; solar photovoltaic energy output; ECOWAS