摘要：Hydroelectric production and hydro-agricultural development are the most frequent motivations for recent projects in sub-Saharan Africa. In the Sahelian zone where the topography is generally flat, hydroelectricity is penalized by the fact that the hydraulic head is most often provided by the dam itself due to the lack of natural waterfall. The hydrological cycle is characterized by a dry season and a wet season, imposing a large regulation reservoir and therefore strong environmental and socioeconomic impacts (loss of traditional crops on the fertile lands of the floodplain, reduction of wetlands and of the services they provide to all activities, significant population displacement, high evaporation, etc.). Synergy with agricultural development and the safeguarding of traditional crops is problematic because the planning of agricultural releases conflicts with energy optimization. However, these regions have significant solar potential and the cost of solar kWh is now lower than that of hydroelectricity in the Sahelian area. The combination of a solar power plant (floating or on land) and a hydroelectric dam optimizes socioeconomic and environmental performance. Through examples, the article shows the benefit of revisiting projects to adapt them to current conditions where the socioeconomic impacts of reservoirs are now at the heart of concerns and where solar energy is becoming a major component of the energy mix.
