Serbia has taken a new step toward the long-planned Đerdap 3 pumped-storage hydropower project, as the U.S. Embassy in Belgrade published a call for expressions of interest aimed at attracting international companies to participate in its development.
The initiative is designed to identify strategic partners capable of supporting the project through engineering services, financing, and construction works. Interested companies have until 25 June to submit letters of intent to Serbia’s Ministry of Mining and Energy, marking the first phase of a broader selection process overseen by a government-appointed working group.
Planned near Golubac on the Danube River, HPP Đerdap 3 is conceived as a large-scale pumped-storage facility intended to significantly improve the flexibility of Serbia’s electricity system. The project would use surplus electricity during periods of low demand to pump water from the Đerdap reservoir into higher-altitude storage basins. During peak demand, the stored water would be released to generate electricity and provide grid balancing and system stability.
With a planned capacity of 2,400 MW, the facility would rank among the largest energy infrastructure projects in Southeast Europe. The concept also includes the potential integration of an additional 400 MW of renewable generation capacity from wind and solar sources. Current estimates place the investment value at around €2.6 billion, with completion targeted for 2038.
The involvement of U.S. companies has been under discussion for several years. Interest from engineering group Bechtel first emerged in 2021, followed by participation in technical studies in 2022. The process gained further momentum after Serbia and the United States signed an intergovernmental energy cooperation agreement in Washington in 2024, which entered into force in March 2025 and created the legal framework for the current tender process.
Despite its strategic importance, the project faces several challenges. Discussions with Romania are still ongoing, as authorities in Bucharest have previously expressed concerns that Đerdap 3 could affect the operation of the jointly managed Đerdap 1 and Đerdap 2 hydropower plants. Bilateral working groups are currently assessing potential hydrological and operational impacts along the Danube.
Environmental considerations have also become a key issue. Experts and conservation groups have warned that construction could affect ecosystems within the protected area of Đerdap National Park, requiring comprehensive environmental impact assessments before any final investment decision.
Given the scale, complexity, and cost of the project, Serbia has also prioritized the smaller Bistrica pumped-storage hydropower project as a more immediate energy storage investment. However, the launch of the international partner selection process signals that Belgrade remains committed to advancing the much larger Danube-based project as part of its long-term energy transition strategy.
