TVS-2M assemblies contained 12 experimental fuel rods
Russian state-owned nuclear corporation Rosatom said it has completed a pilot operation programme for accident tolerant fuel (ATF) at Unit 2 of the four-unit Rostov nuclear power station in southern Russia.
The company said three test fuel assemblies containing advanced fuel rods were loaded into the VVER-1000 reactor unit in 2021 and have now completed three standard 18-month fuel cycles.
The fuel was removed from the reactor during a scheduled outage, marking the end of the test programme.
Rosatom said testing included three TVS-2M fuel assemblies containing 12 experimental fuel rods. Six of the rods had their cladding made of chromium-nickel alloy and the other six had a standard zirconium alloy cladding with chromium coating.
As part of the qualification process, the irradiated fuel will be transferred to the Research Institute of Atomic Reactors in Dimitrovgrad for post-irradiation examination.
Rosatom said chromium-coated zirconium cladding has been identified as the preferred option for commercial deployment, in line with international developments in ATFs.
The company said preparations for serial production are underway at its Chepetsk Mechanical Plant, about 1,200 km east of Moscow, with more than 1,000 chromium-coated fuel rod claddings already manufactured and shipped for further preparation of full assemblies. Each fuel assembly has 312 fuel rods.
ATFs are designed to improve safety and accident tolerance in nuclear reactors. They are engineered to resist severe conditions, including the loss of coolant, without triggering a steam-zirconium reaction that could lead to hydrogen release.
All major global fuel manufacturers have been working to commercialise ATF technology with testing programmes at commercial plants over the past decade.
The four-uniit Rostov nuclear power station in Russia. Courtesy Rosatom.
