Bulgaria / First Westinghouse Fuel Loaded At Kozloduy-5 VVER Reactor Plant ( www.nucnet.org )

Move comes as Sofia aims to end nuclear power dependence on Russia.

Westinghouse-made nuclear fuel assemblies were loaded Wednesday 29 May for the first time in the reactor core of Bulgaria’s Kozloduy-5 VVER-1000 pressurised water reactor unit, the US nuclear company said in a statement.

Westinghouse said the first loading took place at the Kozloduy site in northwest Bulgaria and was inaugurated by a ceremony attended by Bulgarian prime minister Dimitar Glavchev, energy minister Vladimir Malinov and the US ambassador Kenneth Merten.

In December 2022, Bulgaria signed a 10-year contract with US-based Westinghouse for the delivery of nuclear fuel for Kozloduy-5, calling it a “new era” for the country’s nuclear energy sector.

In April 2024, the Bulgarian nuclear regulator issued a licence for Wetinghouse’s RWFA fuel type as 43 lead assemblies arrived at Kozloduy-5.

The Kozloduy nuclear power station said at the time that the new fuel will be loaded into the reactor core during the planned annual outage in early May.

The fuel load is expected to start of the unit’s four-year transition to Westinghouse-made fuel, putting into action efforts to step away from Russian nuclear fuel imports.

There are two 1,000-MW Russia-designed VVER units in operation at Kozloduy. Bulgaria’s only commercial nuclear power station provides about a third of the country’s electricity.

Kozloduy-5 began commercial operation in December 1988 and Kozloduy-6 in December 1993.

Since Russia’s invasion of Ukraine in February 2022, operators of VVER plants in Europe have been looking to diversify nuclear fuel supplies away from Tvel, the fuel wing of Moscow’s state-owned nuclear corporation Rosatom.

Westinghouse already has VVER-1000 fuel supply deals with Finland, the Czech Republic and Ukraine, which was already using Westinghouse fuel for half of its reactors in a push which started in 2014.

After Moscow’s invasion of Ukraine in 2022, Bulgaria accelerated plans to lessen its dependence on Russia for energy. The country has a fuel delivery contract with Tvel since 2019 which is set to expire at the end of 2024 and will not be renewed in 2025.

Sofia has also signed an agreement with France’s Framatome for the delivery of its VVER fuel type for Kozloduy-6, which is expected to arrive “post-2025”, according to earlier reports.

According to Valentin Nikolov, head of the Kozloduy nuclear power station, Kozloduy-6 has enough fuel stored to ensure operation until 2029.