Westinghouse Electric Company have announced a partnership with EDF to explore the functionalities of Westinghouse’s EnCore enhanced Accident Tolerant Fuel (ATF) technology. Westinghouse will study its EnCore fuel in an EDF reactor for potential deployment across the EDF nuclear fleet after 2030. This will be the largest R&D programme on enhanced fuel that Westinghouse has conducted in Europe to date.
Westinghouse will deliver assemblies with Lead Test Rods (LTR) to EDF from its fuel fabrication facility in Västerås, Sweden by 2023. The initiative includes the licensing, qualification, fabrication, delivery and operation of the LTR in an EDF 1300 MWe reactor. Westinghouse also will conduct a post-irradiation exam to verify the enhanced accident tolerance features in EDF’s reactors under operating conditions.
“Westinghouse is a pioneer in the industry-wide ATF initiative, with programmes delivered to US and European customers in 2019 and 2020. We are delighted to collaborate with EDF in this development programme and highly value EDF’s proactiveness and engagement in this critical, long-term effort,” said Tarik Choho, Westinghouse President of Nuclear Fuel.
Westinghouse, Framatome and GE Hitachi with GNF are all working with the US Department of Energy (DOE) to develop new fuels under its Accident Tolerant Fuel Programme. DOE supports these companies by providing irradiation and safety testing, as well as with advanced modelling and simulation, to help qualify their fuels with the US Nuclear Regulatory Commission (NRC).
As part of the programme, lead test rods containing Westinghouse's EnCore fuel technology were loaded into unit 2 at Exelon's Byron NPP in Illinois in the spring of 2019. These were removed after completing their operating cycle during a scheduled outage in the 2020. Post-irradiation testing of the fuel is being carried out by Oak Ridge National Laboratory (ORNL) to help qualify it with the NRC. Westinghouse is testing a chromium-coated zirconium alloy cladding that is loaded with their ADOPT higher density uranium fuel pellets. The programme is receiving support from Idaho National Laboratory and ORNL to provide utilities with longer operation times, increased power outputs and higher fuel burnup. Lead test assemblies of EnCore ATF were also installed in Engie Electrabel's Doel unit 4 in Belgium in 2020.
GE has developed IronClad fuel with support from DOE’s Oak Ridge National Laboratory. It uses a combination of iron, chromium and aluminium for its fuel cladding to improve the fuel’s behaviour under extremely high temperatures. The steel material is intended to have a lower oxidation rate when exposed to high temperature steam, improving the safety margins over zirconium cladding currently in use. GE is also testing a second fuel and cladding concept known as ARMOR. This coated zirconium cladding was developed outside of the DOE programme but is now an integral part of it. Southern Nuclear installed GE-Hitachi ATF fuel cladding technologies in 2018 at unit 1 of the Hatch NPP with samples discharged and shipped to ORNL for further testing in 2020.
Framatome is testing chromium-coated cladding and chromia-doped fuel pellets. The special coating is designed to protect the fuel cladding from damage and oxidation at higher temperatures. The new fuel pellet mixture of chromium oxide and uranium oxide powders is expected to help the pellet last longer and perform better at high temperatures. In 2019, unit 2 at the US Vogtle NPP installed four Framatome-developed GAIA lead fuel assemblies containing accident-tolerant features applied to full-length fuel rods.
Image: Westinghouse fuel assemblies with Encore Accident Tolerant Fuel lead test rods (courtesy of Westinghouse)