Future change of global photovoltaic power potential in a warming world

Photovoltaic power production strongly depends on meteorological conditions. Influencing factors are the air temperature and wind speed at the photovoltaic module, as well as changes in irradiance caused by humidity, clouds and aerosols. Here we analyse the global photovoltaic (PV) power potential and compare the changes therefore between a historical time period (1985 to 2014) and possible futures (SSP1-2.6, SSP2-4.5 and SSP5-8.5) at the end of the 21st century (2071-2100). To that end, we use an ensemble of more than 12 CMIP6 models with interactive aerosol schemes and estimate the potential photovoltaic power generation following Crook et al. (2011). We calculate the change in the PV power potential associated with surface irradiance, temperature, and wind speed between the future and the past, and divide the change in PV power generation into contributions from changes in temperature, cloud cover, humidity, aerosols and wind speed.
Our results point to a global decrease in future PV power potentials due to the rising air temperatures and the associated increase of humidity by -1.2% to more than -3.5% depending on the future scenario. The contribution from changes in cloud cover and aerosols have heterogeneous spatial patterns, with typically stronger influences in SSP5-8.5 compared to SSP1-2.6, e.g. for the clouds. The contribution by clouds is mostly positive, but has a negative effect for PV power potential in the pole regions, over India, and equatorial oceans. The models also show a large spread in their contributions from clouds, especially over Europe and North America. The future change in the contributions from aerosols has beneficial effects for PV power production over Europe and China in all scenarios assesses, but over South-America, Australia and Africa, the contributions from aerosols are positive in SSP1-2.6 but negative in SSP5-8.5 owing to the different behaviour in anthropogenic aerosols and of natural desert-dust emissions. Our study highlights the impacts of CMIP6 model uncertainty in the future development of aerosol burden, the magnitude of future warming, and the unclear response of clouds to warming on estimating future PV power potentials.