Cernavodă to Return in October: 1,400 MW Nuclear Capacity — NRG-IA

Romania could recover approximately 1,400 MW of nuclear capacity in October, which has been unavailable following the shutdown of both reactors at Cernavodă—a return that would significantly shift the balance of the National Energy System ahead of the cold season. Interim Prime Minister Ilie Bolojan stated on the evening of September 10 that, based on current flow rates and forecasts, a restart can be seriously considered towards the end of September, and that the plant will "clearly" return to production "in October." However, this timeline is subject to a decisive physical condition: water. The Danube remains at extremely low levels, and the latest hydrological data does not yet indicate a rapid return to normal seasonal flow rates. Nuclearelectrica has not yet announced a firm date for reconnecting the reactors, stating that operational decisions will be made based on forecasts and available technical data. October becomes the new target for Cernavodă's return Unit 1 of the Cernavodă NPP underwent a controlled shutdown on July 28 after Danube water levels dropped to exceptionally low values. On August 13, Unit 2 was also shut down in a controlled manner, temporarily removing the plant's entire nuclear output from the grid. Since then, Romania has been operating without the two CANDU units, which total approximately 1,400 MW and, under normal conditions, provide a major share of the country's baseload domestic electricity generation. On August 24, Nuclearelectrica confirmed that both reactors were in a safe shutdown state and that there were no operational or nuclear safety risks associated with this status. The company also noted that it would communicate decisions regarding reconnection to the National Energy System based on evolving forecasts and concrete technical data. Bolojan's statement on September 10 introduces an explicit political timeframe for the plant's return for the first time: late September as a window in which a restart can be seriously analyzed, and October as the month in which the prime minister estimates an actual return to production. The Danube remains well below the seasonal average The hydrological situation explains why this timeline cannot yet be treated as a fixed technical date. On September 10, at 07:00, the Danube's flow rate at the entry point into Romania, in the Baziaș section, was 1,350 m³/s , compared to the multi-annual September average of 3,800 m³/s . Downstream of the Iron Gates, flow rates were declining. The forecast from the National Institute of Hydrology and Water Management for the September 10–17 period anticipated a further decrease in the first four days, down to approximately 1,250 m³/s , followed by stagnation and a subsequent recovery toward 1,350 m³/s. Even at the end of the forecast period, the flow rate would remain well below the seasonal average. However, these values alone do not represent the startup threshold for the reactors. The operation of the Cernavodă NPP depends on local water supply conditions, equipment parameters, and compliance with all technical and nuclear safety limits. The flow rate measured at Baziaș is an important indicator of the Danube's overall status, not an automatic start button for the plant. The system compensates for the absence of the two reactors The simultaneous shutdown of both units removed one of Romania's most stable generation sources from the mix. This unavailable capacity must be compensated for by other power plants and, during certain intervals, through imports. Transelectrica indicated as early as August that the National Energy System remains stable, and that available generation capacities and import options can cover Cernavodă's absence. However, security of supply does not equate to a lack of economic cost. When approximately 1,400 MW of nuclear capacity is offline, the system must rely more heavily on other resources, including capacities with different cost profiles and imported electricity during periods when domestic production falls short of consumption. Bolojan directly linked the Cernavodă shutdown to the need for alternative sources and imports. At the beginning of September, authorities indicated a peak-hour deficit of 1,200–1,300 MW , which was partially covered by cross-border exchanges. The return of 1,400 MW would shift the balance ahead of winter Restarting both units would bring back a capacity comparable to the deficit reported during certain peak hours in this period. The primary effect would be an increase in firm domestic generation and reduced pressure on other capacities and import requirements. Bolojan estimates that Cernavodă's return will help balance the system, noting that the plant normally accounts for approximately 20% of Romania's electricity generation . The impact on prices is more complex. A larger, constant domestic supply can ease pressure during deficit periods and improve Romania's position in the regional market, but Cernavodă's return does not mechanically…