Lead test assemblies (LTAs) of Westinghouse-developed nuclear fuel are to be loaded into unit 2 of the Vogtle nuclear power plant, marking the first planned installation of nuclear fuel enriched to more than 5% uranium-235 in a US commercial reactor. The assemblies bring together developments from the EnCore accident-tolerant fuel programme.

ADOPT fuel pellets (Image: Westinghouse)

Southern Nuclear has signed an agreement with Westinghouse to load the four LTAs which will incorporate innovative fuel pellets and cladding developed through the US Department of Energy's (DOE) Enhanced Accident Tolerant Fuel programme. This will be the first installation in Westinghouse's High Energy Fuel initiative.

Accident Tolerant Fuels - ATFs - enhance the tolerance of light-water reactor fuel under severe accident conditions as well as offering improvements to reactor performance and economics. Southern Nuclear Executive Vice President and Chief Nuclear Officer Pete Sena said such "game-changing" technology bolsters round-the-clock plant reliability. "The installation of test assemblies with enrichments that are above historical limits marks another significant advancement in the potential commercial deployment of advanced nuclear fuel technology, which will support our ability to deliver clean, safe, reliable, carbon-free electricity for decades to come," he added.

The Vogtle LTAs will use key components of Westinghouse's High Energy Fuel initiative, including higher enriched rods of up to 6.0% uranium by weight - one percent higher than the current licensed limit. Higher enrichment levels allow higher fuel burnup and an increase in extracted energy, as well as enabling longer fuel cycles of 18 to 24 months, allowing operators to realise cost savings from reduced planned outages.

The LTAs for Vogtle will contain ADOPT higher-density uranium fuel pellets, AXIOM fuel rod cladding and chromium-coated cladding, combined with Westinghouse's advanced PRIME fuel assembly design. ADOPT pellets and chromium-coated cladding are part of Westinghouse's EnCore ATF programme. The LTAs are scheduled to be fabricated this year through a partnership with the Idaho National Laboratory and the DOE.

"These advancements will enable Plant Vogtle to realise its current operational strategy as well as deliver on its long-term needs," said Pam Cowan, president of Westinghouse's Americas Operating Plant Services.

This will not be the first time Vogtle 2 has loaded fuel with Enhanced Accident Tolerant Fuel features. Four Framatome-developed GAIA lead fuel assemblies were loaded into the unit during a refuelling outage in Spring 2019.

Framatome, GE-Hitachi/GNF and Westinghouse are all developing ATF concepts with the help of DOE funding.

Researched and written by World Nuclear News

Date: Saturday, 29 January 2022
Original article: world-nuclear-news.org/Articles/Vogtle-unit-to-test-6-enriched-fuel