SE Raises Output of Mochovce NPP's Fourth Reactor to 35 percent of Capacity

Bratislava, 12 November (TASR) - The fourth unit of Mochovce nuclear power plant (NPP) reached 35 percent of its reactor power at 2.35 a.m. on Thursday and is continuing its power start-up process, Slovakia's dominant power producer Slovenske Elektrarne (SE) announced on Thursday. Since its initial connection to the electricity grid, the reactor has generated almost 16.2 gigawatt-hours (GWh) of electricity. When testing at the current power level is complete, the output will be increased to 55 percent, said SE. "By reaching 35 percent of reactor power, we're entering the next phase of the power-up programme. At each power level, we've a defined set of tests to verify the unit's performance under specific operating conditions. We only proceed to a higher power level when these tests have been completed and evaluated," said Martin Mraz, project manager for completing the construction of SE's Mochovce units. The new unit first supplied electricity to the grid at 8.41 p.m. on 15 October 2026. At a reactor power level of some 20 percent, SE synchronised the first of its two turbo-generators, i.e. aligned its parameters with those of the grid, before connecting it to the grid. Since then, the unit has not only been undergoing the required tests as part of the power start-up process, it's also been generating electricity. As of 8 November, the cumulative power generation of the fourth unit reached 16,184 GWh, equivalent to the annual consumption of some 6,500 households. Testing and measurements of the unit's equipment and systems are continuing at the 35-percent power level in line with the power start-up programme. The reactor power is being increased gradually. When the current stage has been completed and evaluated, the output will reach 55 percent, followed by 75 percent, 90 percent, and 100 percent. The fourth unit is the second of the two new units at Mochovce NPP. Its sister unit, the third reactor, underwent the same power start-up process in 2023. When the fourth unit is operating fully, Mochovce units 3 and 4 will have a combined installed capacity of 942 MW. Each of the new units has a capacity of 471 MW. ko/df