Chapter 21 - Small hydropower plants proliferation and fluvial ecosystem conservation nexus

Abstract

Ever-growing energy demand and transition towards renewable energy have led to a global boom of Small Hydropower Plants (SHPs). Small hydropower plants, particularly run-of-River (RoR) types, are widely perceived as sustainable energy providers. Despite the generally positive perception of social and economic benefits that such renewable energy sources offer to human society, they may substantially alter freshwater ecosystems at different trophic levels. Adequate environmental flows (e-flows) setting is instrumental in mitigating such negative impacts induced by small RoR hydropower plants. However, in general, e-flows design and implantation remain not adequately addressed in small RoR hydropower by resulting in several ecological impacts and some cases, compromising the RoR hydropower profitability. Therefore, to bridge this knowledge gap, this chapter offers an overview of the current status of SHPs development, some of their associated ecological impacts, and e-flows as a potential solution to harmonize conflicting objectives such as maximizing hydropower profitability while ensuring ``good'' ecological status for the freshwater ecosystem. Overall, this chapter highlights the importance of interdisciplinary research and collaborations in enabling the sustainable development of small hydropower plants.