Slovenské elektrárne connects 471 MWe Mochovce 4 to Slovak grid
Phasing-in took place at 20% power at 20:41 on October 15, two days later than planned after a fault in non-nuclear voltage measurement circuits.
Key facts
- Generation equal to about 13% of Slovakia's total current consumption
- Reached criticality on August 6, then equipment tests before physical start-up
- Construction of units 3 and 4 began in 1986 and stalled in 1992
- Completion of units 3 and 4 estimated at EUR6.7 billion (USD7.6 billion)
- Slovak Republic holds 34% stake; Slovak Power Holding BV is majority shareholder
Mochovce 4 began supplying its first electricity to the Slovak grid at 20:41 on October 15, when Slovenské elektrárne phased the 471 MWe VVER-440 unit in with the reactor at 20% power. The unit's generation equals about 13% of Slovakia's total current consumption.
The connection came two days later than originally planned after "a non-standard response was recorded in the electrical voltage measurement circuits of the non-nuclear part of the plant", which required parts of the technical tests to be repeated. The first turbogenerator was aligned and connected; the second must go through a similar process, followed by tests and checks at each power level as output is raised in stages. The final test is a 144-hour run at 100% power. Mochovce 4 reached criticality on August 6.
Construction of units 3 and 4 at the four-unit Mochovce plant began in 1986 and stalled in 1992. The first two reactors came into operation in 1998 and 1999, and a project to complete units 3 and 4 began ten years later at an estimated cost of EUR6.7 billion (USD7.6 billion). Mochovce 3 entered commercial operation in October 2023.
Slovenské elektrárne's majority shareholder is Slovak Power Holding BV, owned by the Czech energy group Energetický a průmyslový. The Slovak Republic holds a 34% stake. Slovakia's five existing reactors generate more than 60% of its electricity; the two at Bohunice entered commercial operation in 1984 and 1985.