Environmental and social impacts of renewable energy and hydropower in Southern Africa can be avoided at modest costs
Based on Wu, G.C., Deshmukh, R., Trainor, A. et al. Avoiding ecosystem and social impacts of hydropower, wind, and solar in Southern Africa’s low-carbon electricity system. Nat Commun 15, 1083 (2024). https://doi.org/10.1038/s41467-024-45313-z
Land and freshwater protections favor more wind, solar, and battery capacity, but at most a quarter of planned or proposed large hydropower projects in Southern Africa’s future low-carbon electricity system.
The Policy Problem
The scale at which low-carbon electricity will need to be deployed to meet economic growth, electrification, and climate goals in Africa is unprecedented. But the potential land use and freshwater impacts from this massive build-out of energy infrastructure is poorly understood. Rapid clean energy development will require careful planning that accounts for competing land use needs, including for conservation and societal use. Hydropower, in particular, is often promoted as a cost-effective low-carbon energy source. However, hydropower infrastructure can displace communities, destroy habitat, and disrupt river ecosystems. Wind, solar, and battery technologies are potential substitutes, but these technologies have their own land use requirements. How can we balance tradeoffs between energy infrastructure and social and environmental goals?
Key Findings and Proposed Solutions
Without socio-environmental protections or a climate goal, wind and solar account for half the new cost-optimal generation capacity and total energy generation needed to meet electricity demand in Southern Africa in 2040.
About 40% of planned or proposed hydropower capacity has significant social and/or environmental impacts, such as altering free-flowing rivers in sensitive habitats or displacing communities. Without siting protections, more than 150,000 people could be displaced by hydropower.
Increasing wind (+7.5%), solar (+29%), and battery capacity (+23%), while reducing hydropower capacity (−31%), can meet forecasted energy demand and a 50% reduction in carbon emissions in 2040 compared to 2020, while protecting socially and environmentally important areas in Southern Africa.
Achieving an environmentally sustainable, more socially equitable, and low-carbon electricity system for Southern Africa is slightly more expensive compared to unrestricted, higher-impact development—3.8% more for all socio-environmental protections and 6.8% more for all socio-environmental protections with a low-carbon target.