Floating solar photovoltaic (FPV) panels are a solution to increase renewable energy in Africa's future energy mix, reducing impacts on ecosystems and communities compared to building new hydroelectric dams. This finding is the result of a study conducted by researchers at the Environmental Intelligence for Global Change Lab led by Prof. Andrea Castelletti from the Department of Electronics, Information and Bioengineering, Politecnico di Milano, who analyzed FPV technology in Africa's energy system.
The study, published in Nature Energy, is among the first to examine FPV on a continental scale, finding that floating photovoltaic panels installed in existing water reservoirs could produce between 20 and 100 percent of the electricity expected from hydropower dams already planned in Africa. Using a state-of-the-art energy planning model that covers the continent's entire energy system, the researchers found that FPV is cost-competitive with other renewable sources and therefore represents a key element of Africa's future energy mix.
By using floating solar and reducing dependence on hydropower, developing economies can ensure a more stable and robust energy supply to hydrological uncertainties caused by climate change. In addition, floating solar would avoid many of the negative impacts that new large dams could have on downstream communities and river ecosystems.
Researchers conducted a study of the transboundary Zambezi River Basin and found that the planned investment in the construction of three new dams could be used more efficiently by supplementing the energy supply with floating solar. Compared to intensive solutions such as dams, this approach resulted in 12 percent less variability in electricity supply and was more robust against drought.
The work highlights the importance of integrated resource planning and consideration of transboundary impacts in the path of sustainable development. Traditional energy-water modeling often considers single sectors such as hydropower in isolation. However, this study presents advanced multi-sectoral modeling that can reveal and balance trade-offs between energy, agricultural, environmental protection and economic development goals within transboundary river basins.
The study results suggest that the benefits of avoiding the construction of new dams through floating solar deployment strategies could outweigh the potential negative impacts on other activities practiced in the reservoirs where such panels would be installed, such as fishing or tourist boating. But a collective effort is still needed to improve FPV technology and ensure its responsible implementation through integrated planning processes and active involvement of local stakeholders.
While the economic factor for FPV is favorable, the ecological and social impacts of FPV are not yet fully known. However, these potential impacts would be far less severe than those of building new hydropower dams, which can irreversibly disrupt river ecology, displace communities, and exacerbate regional tensions regarding shared water resources.