Action towards increase in sustainable hydropower: A Pan-European assessment and strategy

ABSTRACT Hydropower plays essential role in Europe’s energy landscape, contributing significantly to the continent’s renewable power generation mix. However, in the context of global sustainability goals and the accelerating impacts of climate change, there is an urgent need to reassess and enhance the sustainability of hydropower development. This includes not only minimizing social and environmental impacts but also addressing legislative and governance challenges that hinder responsible growth. These dimensions are at the core of the COST Action CA21104 – Pan European Network on Sustainable Hydropower (PEN@Hydropower) , which brings together more than 375 members across five working groups spanning technical, environmental, economic, and social perspectives. This paper presents a synthesis of PEN@Hydropower activities, focusing on the underutilization of hydropower potential in four European countries—Slovenia, Lithuania, Poland, and Iceland. These countries, often underrepresented in the literature, offer valuable insights into how multi-level governance and stakeholder dynamics shape the implementation of EU climate and energy policies. Drawing on qualitative methodology research methods within the COST Action CA21104 framework, the study combines in-depth analysis of revised National Energy and Climate Plans (NECPs) with participatory stakeholder mapping based on Reed’s methodology ( Reed et al., 2009 ). The findings reveal a significant legislative gap between EU-level climate-neutrality objectives (such as those set out in the European Green Deal) and environmental protection obligations (for example, the Water Framework Directive). This gap permeates governance structures and ultimately constrains hydropower development. The stakeholder workshop held in Reykjavík further confirmed that this misalignment disproportionately affects actors such as civil society, academic experts, and hydropower operators and suppliers, whose perspectives are essential for achieving a more coherent, climate-informed governance strategy. In this context, the paper underscores the relevance of PEN@Hydropower’s planned output: practical guidelines for hydropower plant operators, but also for stakeholders wishing to construct new facilities or renovate existing ones, aimed at bridging the gap between policy and implementation and supporting a more harmonized and sustainable approach to hydropower development across Europe.