Slovakian utility Slovenské Elektrárne has started operating unit 3 of the Mochovce nuclear power plant at full power.

According to the company,  the start-up process for the VVER-440 reactors involves gradual increases in power, with tests carried out to ensure efficacy at each level of power output.

Discover B2B Marketing That Performs

Combine business intelligence and editorial excellence to reach engaged professionals across 36 leading media platforms.

Find out more

In February 2023, unit 3’s power was increased to 35% of overall capacity, then to 55% in March, 75% in July and 90% in August. The Slovak Nuclear Regulatory Authority told Slovenské Elektrárne it could now raise reactor output to 100%. The company will perform a 144-hour trial run with power at maximum capacity.

Peter Farkaš, operations manager at the Mochovce plant, said: “After demanding tests required to prove the safe operation of unit 3, we have reached the final stage. Full-scale tests are planned for the end of September and the beginning of October, including the 144-hour trial run. All tests have so far confirmed the readiness of the new unit for long-term safe and CO₂-free power generation.”

Construction of the first two units of the Mochovce plant began in 1982, using VVER-440 V-213 reactor units. Units 1 and 2 became operational in 1998 and 1999, respectively. By June 2008, after assistance from Western companies with upgrades, Mochovce 1 and 2 produced 436MW.

Work on units 3 and 4 started in 1986 but halted in 1992. Construction began again in 2009, but due to political wrangling, including opposition from Austrian environmental organisation Global 2000, it was not finished until 2021. Output began in October 2022. Unit 4 is scheduled to reach maximum output up to two years after unit 3. When all units are operating at full capacity, each will be able to provide 13% of Slovakia’s electricity needs.

GlobalData Strategic Intelligence

US Tariffs are shifting - will you react or anticipate?

Don’t let policy changes catch you off guard. Stay proactive with real-time data and expert analysis.

By GlobalData

Recently, Canada granted Romania C$3bn (10.5bn lei) to develop nuclear power infrastructure. This will be used to build units 3 and 4 of the Cernavoda plant, which will generate 36% of Romania’s electricity upon completion.

Power Technology Excellence Awards - Nominations Closed

Nominations are now closed for the Power Technology Excellence Awards. A big thanks to all the organisations that entered – your response has been outstanding, showcasing exceptional innovation, leadership, and impact.

Excellence in Action
Recognised with three 2025 Power Technology Excellence Awards, Hover Energy is at the forefront of intelligent microgrids and distributed renewables. Explore how its AI-enabled Microgrid Management System™ , strategic partnerships and networked microgrids are rebuilding the grid from the ground up for a more flexible, resilient energy future.

Discover the Impact