Seasonal and diurnal variability of renewable resources in South Africa: Data-driven insights for hybrid system design and policy implementation

South Africa’s energy transition, guided by the Integrated Resource Plan 2030 and Renewable Energy Masterplan, requires a clear understanding of seasonal and diurnal variability in renewable resources for effective hybrid system deployment. This study provides a high-resolution spatiotemporal analysis of solar and wind resources from 2020 to 2024 across all nine provinces, integrating ground-based and satellite datasets to enhance data reliability. Results show that the Northern Cape recorded the highest solar potential, with mean Global Horizontal Irradiance (GHI) of 251.1 W/m² and Direct Normal Irradiance (DNI) of 304.9 W/m², while KwaZulu-Natal and Mpumalanga had the lowest GHI (∼195 W/m²) due to cloud cover and humidity. Wind speeds above 6 m/s were consistent in the Northern and Eastern Cape, supporting complementary night-time generation. A 2.3 GW hybrid techno-economic evaluation combining PV, wind, and storage showed that optimized provincial configurations reduce the levelized cost of energy (LCOE) by up to 18 % and curtailment by 25 %, while improving storage utilization and grid reliability. Sensitivity analysis indicated that ±20 % variations in capital cost, O&M cost, and storage subsidies affected LCOE by 3–11 %, highlighting cost resilience across regions. The findings provide data-driven insights into resource variability and hybrid energy economics, supporting evidence-based policy, investment prioritization, and grid resilience planning for South Africa and comparable renewable-rich developing regions. • Integrated ground and satellite data to build hourly (2020–2024) renewable resource profiles for all nine South African provinces. • Assessed provincial hybrid PV–wind–storage systems to identify cost-optimal and resilient energy configurations. • Identified strong seasonal and diurnal variability, with peak solar in Northern Cape and night-time wind in Eastern Cape. • Showed hybrid systems with storage cut LCOE by up to 18 % and curtailment by 25 %, supporting grid planning decisions.