Press Release Slovenské elektrárne – Slovakia’s new nuclear reactor Mochovce 3 is officially connected to the grid. It will provide 13% of the country’s electricity and when the next reactor is finished, Slovakia will have an almost completely decarbonized grid.
After the completion of the prescribed tests, Slovenské elektrárne, a.s., brought steam to the turbines and connected Mochovce 3 to the grid for the first time at 20% power.
On Tuesday, 31 January 2023 at 10:57 PM, Slovenské elektrárne connected to the grid the first of the two turbine generators of the Mochovce 3 nuclear power plant. The plant reached this important milestone less than three weeks after the Nuclear Regulatory Authority of the Slovak Republic gave its approval for the beginning of the power start-up on 13 January 2023.
After the transition to power start-up, tests were conducted successively at the levels of 5, 15, and 20% of the reactor’s rated power, with measurements and tests of both nuclear and non-nuclear parts of the plant. The secondary circuit was heated up and steam lines were blown down, cold and hot flushes of turbine condensers and low-pressure regenerators, as well as feedwater lines, were done, and tests of steam generator relief valves were carried out, which were heard in the wider vicinity of the plant.
After successful preparation and performance of the tests necessary to start the turbines, steam was brought into the turbines for the first time over the weekend (28 and 29 January), spinning them step-by-step up to their rated speed of 3,000 rpm.
Slovenské elektrárne, a.s. also tested the functionality of all electrical protections of the generator itself, the block transformer, and finally the 400 kV line connecting the plant to the power system via the Veľký Ďur substation. Electricity will flow along this route to Slovak consumers.
Once this part of the power start-up was completed, Slovenské elektrárne, a.s. could proceed to the actual synchronization of the first turbine-generator with the grid at 20% of the reactor’s nominal power and the Mochovce 3 began to supply the first electricity to the grid.