Accident tolerant fuel completes full operating lifecycle

Wednesday, 23 October 2024

The assemblies - the first full-length PROtect Enhanced Accident Tolerant Fuel fuel rods with both pellets and cladding to be placed in an operating pressurised water reactor - were inserted into Vogtle unit 2 in April 2019. Plant operator Southern Nuclear removed and inspected the four assemblies with Framatome's assistance following the completion of the operating cycle. It was determined that the fuel demonstrated expected results and excellent performance, Framatome said.

Accident tolerant fuels employ advanced cladding materials and fuel pellet designs to increase the safety and performance of nuclear fuels. As well as enduring the loss of cooling in a reactor core for longer than current fuel designs and widening the existing safety margin for nuclear plants, and they can also improve the performance of existing nuclear plants with longer-lasting fuel as well as paving the way for licensing fuels for advanced reactors.

The US Department of Energy has been supporting the development of accident tolerant fuels by Framatome, Westinghouse and GE Hitachi/Global Nuclear Fuels through its Accident Tolerant Fuel programme, which was launched in 2012. The programme aims to see advanced fuel concepts being brought to market by 2025.

"This is a significant milestone for our programme and through our collaboration with the US Department of Energy and Southern Nuclear we bring this new and innovative technology one step closer to commercial operations," said Lionel Gaiffe, senior executive vice president, Fuel Business Unit at Framatome. "The success of this project demonstrates accident tolerant fuel readiness for the safe and reliable generation of our clean energy future."

The four GAIA lead fuel assemblies loaded into Vogtle 2 were fabricated at Framatome’s manufacturing facility in Richland, Washington. Each assembly included four lead test rods, for a total of 16 lead test rods with the company's advanced chromium coating added to the M5 Framatome zirconium alloy cladding, and chromia-enhanced fuel pellets were included in all fuel assembly rods. The chromium-coated cladding improves high-temperature oxidation resistance and reduces hydrogen generation in the event of loss of cooling. The innovative coating also offers increased resistance to debris fretting, reducing the likelihood of a fuel failure during normal operations.