Danube inflows in Serbia are running at about half the long-term average and are approaching the river’s biological minimum. Forecasts provide little indication of a material recovery over the coming weeks. The sustained low water situation is increasing the operational and financial pressure on state-owned utility EPS.
Đerdap hydropower output reduced under low river conditions
Serbia’s Đerdap hydropower cascade is generating less power as inflows remain weak. Đerdap 1 has recently produced slightly more than 5,000 MWh per day, about one-third of its normal output. That corresponds to an average of roughly 208 MW, versus an implied normal level of about 625 MW. The resulting lost generation is close to 10 GWh per day.
Replacing the missing energy at wholesale prices of €100–130/MWh could cost approximately €1–1.3 million per day. The estimate excludes congestion effects, balancing requirements, and differences between hourly import prices. The financial impact increases when low hydrology aligns with evening scarcity or regional heat-driven demand.
Hydrological limits and availability of refurbished units
EPS said all refurbished Đerdap units remain technically available. The units are operating at the maximum output permitted by current river conditions. EPS attributed the shortfall to hydrological constraints rather than mechanical issues. As a result, conventional availability improvements have limited effect.
Pumped storage and thermal generation at Kostolac
The modernised Bajina Bašta pumped-storage plant provides some relief for EPS’s balancing needs. EPS can buy electricity during low-priced solar hours, pump water into the upper reservoir, and generate during more expensive evening periods. This approach reduces replacement-energy costs but cannot fully offset sustained losses from the larger Đerdap cascade.
Low Danube water levels are also restricting cooling capacity at the Kostolac thermal power plants. That constraint is forcing reductions in thermal generation. With hydro and coal assets affected by the same river conditions, EPS faces a correlated risk across its production portfolio.
System stability alongside shifting economic burden
Serbia’s electricity system remains operationally stable despite the generation constraints. However, the economic burden is shifting toward imports, short-term trading, and careful use of stored hydro resources. The Danube drought has become a balance-sheet issue as well as a generation constraint.
