Key insights from Hydropower Day 2025: Flexibility, innovation, and environmental stewardship driving Europe’s renewable energy future

*Presentations available via ETIP HYDROPOWER CONSULTATION PLATFORM: https://hydro-consultation.eu/participant-area/ *

On 8 April 2025, leading experts, policymakers, and industry stakeholders gathered at Hydropower Day 2025 in Brussels to discuss the evolving role of hydropower in Europe’s energy transition. Hosted by ETIP HYDROPOWER, the event provided a platform for knowledge exchange, best practice sharing, and forward-looking discussions on sustainability, innovation, and climate resilience. With growing concerns over energy security, decarbonisation, and environmental sustainability, this event emphasised the essential role of hydropower in the clean energy future.

Europe needs a resilient energy system, and that means smart legislation, strong industrial strategy, and bold investment in hydropower R&I to stay ahead globally.

The keynote session emphasized hydropower’s ability to balance energy, water, food, and environmental needs. Thomas Schlecker (DG RTD) highlighted hydropower’s contributions to sustainability. In this session, the focus was on how European Hydropower could support the overall objectives set by Sustainable Development Goals (SDGs). Miroslav Marence (IHE) talked to us about the key role of energy in the European Policies and the status of the competitiveness in the hydropower sector. Next, Adel el Gammal (EERA) showcased the industry's strength in delivering green and flexible innovation globally and the role of EERA in R&I.

The panel discussion was composed by Heike Bergmann (VOITH Hydro), Eivind Hodne Steen (Eurelectric); Miroslav Marence (IHE Delft) and Adel El Gammal (EERA) and moderated by Greg Arrowsmith (EUREC). The group discussed about the reasons why Pumped-Storage Hydropower (PSH) is not scaling as fast as it should be despite its critical role: PSH has the characteristics to be the key flexibility provider with the growth of wind and solar. However, the issue of the permitting process was also highlighted as one of the main blockers of this technology.

Real-world hydropower projects show how we can meet demand, but financing and policy must catch up.

Session 1 was devoted to Strengthening Energy Security. Franck Dia Wagoum (ENTSO-E) stressed that flexibility is no longer optional in the European grid, emphasising hydropower’s role in ensuring stability both in long-term and short-term to manage variability. Michaël Plaschy (Nant de Drance, Alpiq) shared real-world experience operating a large, pumped storage plant under market constraints. He explained that financing and environmental concerns remain the major barriers for expansion. Finally, Atle Harby (SINTEF) presented research on the impact of large-scale hydropower in Norway on electricity prices and environmental conditions. He highlighted that interconnections among countries not only would lower energy prices but also promote energy solidarity in Europe.

The panel discussion in the first session featured the previously mentioned speakers, with Wolfram Malzfeldt (BDW), Gordon Edge (IHA), and Elena Vagnoni (EPFL) joining them, while Leonardo Nibbi (Università degli Studi di Firenze) moderated the session. The panel discussion brought perspectives on hydropower’s role in enhancing flexibility and resilience within Europe’s energy system. Speakers highlighted the potential of run-of-river plants to support grid stability sharing practical examples from Switzerland and Norway, and stressed the importance of modernisation, fair compensation for flexibility services, and a balanced approach to environmental considerations. Technological advancements, such as those demonstrated in the XFLEX HYDRO project, and the use of AI for improved operations and monitoring, were agreed as key areas to support the future development of sustainable and efficient hydropower.

Balancing Energy Production and Environmental Preservation for Long-Term Sustainability

The second session of the day revolved around environmental responsibility in hydropower. Tasniem Siegfried Jawaid (ETIP HYDROPOWER/EREF) told the audience about National interpretations of regulations on nature in the absence of an EU law on nature restoration. Christoph Hauer (BOKU) highlighted the importance of sediment management for both ecological and technical functions. He also explained that removing obstacle barriers does not solve the problem as it does not erase sediment dynamics but rather alters their pattern creating new concerns.

Agnès Barillier (EDF), spoke about how hydropower’s environmental impact requires a context-specific approach that considers water flows, sediment continuity and fauna and flora behaviours (among other site-specific characteristics) to provide tailored measures that need to be monitored over time. Finally, Joao Costa (HSA) explained the audience how the Hydropower Sustainability Alliance offers a globally recognised certification system that enhances credibility, financial value and environmental accountability. The certification is done via independent auditing, thus ensuring stakeholder transparency and reliability.

The panel discussion, moderated by Natalie Rojko (Energyminer), also included Jeffrey Tuhtan (TalTech), Ólafur Jónsson (Landsvirkjun), and the previously mentioned speakers. The panel debated about how important is that the ecosystem restoration efforts look beyond hydropower and consider the broader environmental context. As highlighted before, there is no one-size-fits-all approach and each water body must find site-specific solutions. In addition, they also underlined that long-term monitoring, and real-world experiences are vital to support the measures.

Climate resilience starts with smarter hydropower, tracking emissions and designing for extreme climate challenges

The third session focused on the work done by the Working Group 3 of ETIP HYDROPOWER, that is, the role of hydropower tackling climate challenges.  Arianna Trevisiol (RSE Italy) highlighted how climate change will impact hydropower production in Europe, with northern regions potentially benefiting from increased water inflow, while southern areas, like Portugal and Italy, could see a 20-30% decrease in generation due to warmer temperatures and reduced rainfall. Next, Martin Fuchs (AFRY) emphasised that while hydropower plants contribute to emissions, they are vital for flood control, drought mitigation and providing low-carbon electricity. He also said that the sector needs to improve the climate resilience aspect of hydropower projects with proper adaptation and mitigation measures.

The last presentation was done by Christos Dimou (PPC) who brought us the case of Greece’s reliance on large hydropower for energy generation. He stressed the increasing importance of PSH, the impact of droughts on energy prices and the need for new reservoirs, all with the focus on PSH as the future solution of these challenges.

For the panel discussion of session three Aðalbjörg Birna Guttormsdóttir (DG ENV, EC) and Alessandra Carota (ENEL) joined the group of speakers. They discussed that the global push for greener hydropower is growing, with Europe leading the way setting standards. Hydropower plays a crucial role in the achievement of EU’s climate goals but needs to adapt to the rising climate risks. This could be addressed by smarter emissions tracking and improving efficiency though smarter technologies and modernising plants.

Conclusion and looking ahead

Hydropower must transform into a flexible and climate-resilient source of energy generation to meet the evolving needs of demand and climate change. With Europe leading on sustainability standards, hydropower places itself and an essential asset to achieving EU’s climate goads while tackling environmental concerns such as biodiversity loss and water ecosystem damage. As extreme weather patterns become more frequent, hydropower must bet on innovative solutions that prioritise both, sustainability and efficiency.

Looking forward, the key lies in embedding flexibility into the hydropower systems. This would allow them to respond dynamically to changes in water flows. Collaboration and innovation were also highlighted as crucial in minimising environmental impact while boosting hydropower’s role in water resilience. The hydropower sector must unite with a clear and powerful voice driving flexibility, environmental protection and climate adaptation forward.

To conclude the event, Anton Schleiss (ETIP HYDROPOWER / ICOLD) and Denis Aelbrecht (EDF/ ETIP HYDROPOWER GB) highlighted the importance of raising awareness and driving innovation in the sector. A key challenge is to strengthen ETIP HYDROPOWER’s role in unifying the voice of the hydropower community which requires the support from all stakeholders.

Introduction of the Hydropower Day 2025 by Anton Schleiss (ETIP HYDROPOWER/ICOLD) 

ABOUT ETIP HYDROPOWER:

The ETIP HYDROPOWER project was shaped following the previous HYDROPOWER EUROPE Forum project which was funded by the European Union’s Horizon 2020 Research and Innovation programme that ran between 2018 and 2022.  The hydropower Research and Innovation Agenda (RIA) and the Strategy Industry Roadmap (SIR) were created under the HYDROPOWER EUROPE project.

The ETIP HYDROPOWER project is funded by the European Union under the Horizon Europe programme and the consortium comprises eight expert organisations including: EUREC, SAMUI FRANCE, EUROPEAN ASSOCIATION FOR STORAGE OF ENERGY (EASE), COMMISSION INTERNATIONALE DES GRANDS BARRAGES (ICOLD), VGB POWERTECH, ZABALA BRUSSELS, EUROPEAN RENEWABLE ENERGIES FEDERATION (EREF) and INTERNATIONAL HYDROPOWER ASSOCIATION (IHA).

The project started in September 2022, is expected to end in August 2025 and has been granted EUR 1 million Euros under the call dedicated to “Support to the activities of the ETIPs and technology areas of the SET Plan”.