Variability in solar based power generation at the Eastern Mediterranean

The utilization of solar photovoltaic (PV) systems is pivotal towards reducing carbon dioxide emissions within the global energy infrastructure. Climate change is expected to affect atmospheric parameters such as cloudiness and aerosol, which are key drivers for the amount of solar radiation reaching the ground thus modifying solar-based power generation.In this study, we investigate the spatial and the temporal variability of PV plant energy output at the Eastern Mediterranean during the period 1950-2100, with respect to the corresponding changes of the shortwave downwelling solar radiation, aerosols, cloudiness, and near-surface air temperature, which are crucial for estimating the solar energy production. The trends of the aforementioned variables, obtained from the analysis of gridded data retrieved from climate model projections, particularly from the “Region 4: Europe (EURO)” domain of the Coordinate Regional Downscaling Experiment (CORDEX). Aiming to achieve an optimal approximation of the changes in aerosol concentrations, we employed the CNRM-ALADIN63 Regional Climate Model (RCM) which interactively considers them. The boundary conditions are derived from projections of the CNRM-CERFACS-CM5 Global Climate Model (GCM) within the 5th phase of the Climate Model Intercomparison Project (CMIP5), encompassing the historical period (1951-2005) and future scenarios (2006-2100) under Representative Concentration Pathways (RCP) 2.6, 4.5, and 8.5. For the determination of the PV energy output, we performed numerical simulations with the Global Solar Energy Estimator (GSEE), considering as input values the downwelling solar radiation, air temperature, as well as the tilt, capacity, and orientation of the hypothetical solar panels. Data from the Copernicus Atmosphere Monitoring Service (CAMS) and Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2) datasets are also used for the intercomparison of the modelled downwelling solar radiation. Our results are in line with the findings of previous studies that assessed such changes capable of causing surplus or deficit in relation to solar energy production. Furthermore, we show that changes can vary significantly on a regional level.Nikolaos Papadimitriou would like to acknowledge funding for the participation at EMS2023 from the COST Action HARMONIA (International network for harmonization of atmospheric aerosol retrievals from ground based photometers), CA21119. The work has been also supported by the action titled “Support for upgrading the operation of the National Network for Climate Change (CLIMPACT II)”, funded by the Public Investment Program of Greece, General Secretary of Research and Technology/Ministry of Development and Investments.