The U.S. Embassy in Belgrade has published a call for expressions of interest to attract international companies to the development of the Đerdap 3 pumped-storage hydropower project. The initiative is aimed at identifying strategic partners able to contribute engineering services, financing, and construction works. Interested firms must submit letters of intent to Serbia’s Ministry of Mining and Energy by 25 June.
This call represents the first phase of a broader selection process. A government-appointed working group oversees the next steps following the submission deadline. The embassy’s notice frames the process as an effort to bring external participation into project development.
Đerdap 3 location, design and planned scale
HPP Đerdap 3 is planned near Golubac on the Danube River. The concept is designed as a large-scale pumped-storage facility intended to increase flexibility in Serbia’s electricity system. It would use surplus electricity during low-demand periods to pump water from the Đerdap reservoir into higher-altitude storage basins.
During peak demand, stored water would be released to generate electricity. The same operating approach is intended to support grid balancing and system stability. The project is also described as potentially integrating an additional 400 MW of wind and solar generation capacity.
Serbia estimates the investment value at around €2.6 billion. The planned installed capacity is 2,400 MW, placing it among the largest energy infrastructure projects in Southeast Europe. Completion is targeted for 2038.
U.S. engagement and tender framework
Engagement by U.S.-linked companies has been discussed for several years. Interest from engineering group Bechtel first appeared in 2021, followed by participation in technical studies in 2022.
The current development process gained momentum after Serbia and the United States signed an intergovernmental energy cooperation agreement in Washington in 2024. That agreement entered into force in March 2025, establishing the legal framework for the tender process connected to Đerdap 3.
Romanian talks and environmental assessment requirements
The project’s progress includes ongoing discussions with Romania. Authorities in Bucharest have previously raised concerns that Đerdap 3 could affect operations at the jointly managed Đerdap 1 and Đerdap 2 hydropower plants.
Bilateral working groups are assessing potential hydrological and operational impacts along the Danube as part of these discussions. Environmental considerations are also central to planning, with experts and conservation groups warning that construction could affect ecosystems within the protected area of Đerdap National Park.
The warnings point to the need for comprehensive environmental impact assessments before any final investment decision. Serbia has also prioritized a separate pumped-storage option, the smaller Bistrica project, as a more immediate energy storage investment.
