Political instability influence on hydropower planning in Africa: a continental scale analysis

As many developed countries prepare their transition to net zero emissions energy systems, Africa must plan a substantial expansion of its energy production sources, to meet the growing demand driven by increasing population and energy access. Among the existing capacity expansion potential, hydropower plays an important role in providing clean and cheap electricity. Yet, large hydropower schemes bring many negative social, environmental, and geopolitical externalities.Least-cost optimization models constrained to satisfying predefined energy demands are used for large-scale energy system planning. Multi-objective optimization models can also incorporate environmental impacts in energy system planning, for instance by constraining the optimal solutions on GHG emissions or geomorphologic connectivity losses. However, these traditional techno-economic approaches overlook governance considerations, which are relevant to energy security, especially in unstable and conflictual political contexts. In fact, concerns about political instability are ranked among the main investment risks for foreign investors in developing countries. The subject becomes even more significant in transboundary river basins, where institutional stability and the absence of conflicts are crucial for effectively building and operating large hydropower projects.To assess the political risks associated with the hydropower sector, we examine six pathways of energy generation for the African continent, from 2020 to 2050, developed using the OSeMOSYS-TEMBA energy system model. The model considers more than 600 existing and future hydropower projects in all countries of continental Africa, including available information for each individual power plant. Moreover, it incorporates ISIMIP2b scenarios to integrate coherently final energy demands, land-use change, and climate impacts on water availability.For each scenario considered, the political risk deriving from the associated electricity generation and exchange patterns is characterized at the country-level using six energy-related dimensions. The more vulnerable transboundary river basins are then selected by intersecting the countries with high energy-related political risk and regions with high hydro-political conflict based on existing literature. We use a worst-case perspective for these basins and assume that electricity generated from planned or existing hydropower projects would not be exchanged between co-riparian countries due to the lack of cooperation. Finally, the impacts on the energy system are re-evaluated for the resulting cost-optimal energy system reconfiguration, and the difference with the fully connected solution is assessed.Our results show that integrating political stability in energy system planning can produce precise spatial information about potential risks. Indeed, the lack of cooperation in transboundary river basins affected by high political instability can emphasize pre-existing vulnerabilities. Since this issue severely influences decisions related to energy planning on a continental scale, energy analysts can improve energy security using these results to design capacity expansion robust to political shocks.