Slovakian nuclear power plant: Mochovce 3 reaches 90% capacity

The Mochovce nuclear power plant in Slovakia is gradually increasing the output of its third reactor unit to 90%, with a view to reaching 100%. This marks the end of the energy start-up phase, strengthening the country's energy supply and paving the way for Slovakia to become a net energy exporter.

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After methodically carrying out a series of ramp-up tests, the Mochovce nuclear power plant in Slovakia has increased the capacity of its third reactor unit to 90%, bringing it closer to the final target of 100% total power, which will mark the end of the energy start-up phase and make a significant contribution to the country’s energy supply.

Energy progress at Slovakia’s Mochovce nuclear power plant: Gradual power increase for third reactor unit

The start-up process involves gradual increases in power, with tests carried out before increasing the level. The unit’s output was increased to 55% in March and to 75% in July.

“After successfully completing all energy start-up tests at a power level of up to 75% of the reactor’s rated power and submitting the test report to the Slovak Nuclear Regulatory Authority, Slovenské elektrárne has increased the reactor power of the third unit of the Mochovce nuclear power plant to 90%,” said the company.

To date, the unit has supplied around 650,000 MWh of electricity to the grid, which, according to Slovenské elektrárne, corresponds to the annual consumption of 260,000 households.

“Testing at 75% power level was completed without delay, bringing us closer to full power at Reactor 3,” said Mochovce plant manager Martin Mráz.

On the road to full power: Mochovce nuclear power plant nears final commissioning stage

Once testing has been completed at 90%, the reactor’s power will be increased to 100%.

“Full functionality of the third unit and achievement of the project parameters will be confirmed by a 144-hour demonstration at 100% power, which will end the energy start-up phase,” said Slovenské elektrárne. “This milestone should be reached between September and October.”

Construction of the first two VVER-440 units at the four-unit Mochovce power plant began in 1982. Work on units 3 and 4 began in 1986, but stopped in 1992. The first two reactors were completed and went into service in 1998 and 1999 respectively, and a project to complete units 3 and 4 was launched ten years later. The schedule for unit 4 was drawn up one or two years later than for unit 3.

Each unit will be able to supply 13% of Slovakia’s electricity needs when operating at full capacity. Slovakia hopes to become a net energy exporter once the two new Mochovce units are both operational.

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