A Russian-made AFT bundle of the type loaded at Rostov-2. Courtesy Tvel. The first Russian-made fuel bundles containing experimental advanced technology fuel (ATF) rods have been loaded into VVER-1000 reactor core at Unit 2 of the Rostov nuclear power station in southwest Russia.

Each of the three combined TVS-2M fuel assemblies, designed for Russia’s VVER-1000 power reactors, contains 12 experimental fuel rods. Six of them have their cladding made of chromium-nickel alloy, and the other six have a standard zirconium alloy cladding with chromium coating.

The fuel was loaded into the 950-MW plant during a scheduled maintenance and refuelling and the plant has now returned to service.

Russia’s state nuclear fuel company Tvel said ATFs can endure the loss of active cooling in a reactor core for much longer than current fuel, improve nuclear plant performance and reduce operational and maintenance costs.

Tvel said a team of specialists from state nuclear corporation Rosatom validated plans for the ATF loading at Rostov-2 and the project was overseen and approved by regulator Rostekhnadzor.

Rosatom has been testing Russian-designed ATF since 2018. The experimental assemblies have passed two full irradiation cycles in Russia’s MIR research reactor.