Hydropower is renewable, but mostly not environmentally friendly. A study led by the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) shows for Romania how the expansion of hydropower runs counter to the goals of EU environmental policy. Hydropower conflicts with the requirements of the Flora-Fauna-Habitat Directive (Natura 2000) and the European Water Framework Directive (WFD): Around half of the existing and planned hydropower plants in Romania are located in nature conservation areas. These are mostly small plants that contribute only 3 percent of Romania's electricity generation, but threaten biodiversity. Therefore, European energy policy urgently needs to be aligned with the goals of the EU Biodiversity Strategy, the researchers warn. Otherwise, there is a risk of significant losses of freshwater biodiversity, and the goals of the EU Green Deal would not be achievable.