Resumen
The main objective of the present study is to rank South African provinces on the basis of incoming solar radiation. The surface incident shortwave flux (SWFlux, Wm-2) of NASA Modern-Era Retrospective Analysis for Research and Applications (MERRA 2D) reanalysis data for the period 1980?2009 over South Africa was analysed on annual, seasonal and monthly scales. The monthly mean ± standard deviation values of SWFlux for the period revealed that, Northern Cape received the most (267.38 ± 4.32 Wm-2) incoming solar radiation throughout the year, followed by North West (263.37 ± 7.13 Wm-2) and Free State (259.20 ± 7.66 Wm-2). The northern region of Limpopo also showed a good amount of incoming solar radiation (257.95 ± 6.16 Wm-2) at the surface. KwaZulu-Natal received least (232.99 ± 7.02 Wm-2) amount of mean monthlysolar radiation in comparison with other provinces. On an annual scale, the Northern Cape ranked first, and on seasonal and monthly scales North West ranked first. Limpopo and Free State also performed well in the present study.