Unit 1 of the Edwin I Hatch nuclear plant in the USA has begun operating with Global Nuclear Fuels (GNF) test accident-tolerant fuel assemblies, the first of its kind to be installed in a commercial nuclear reactor.
Hatch is a two-unit BWR plant owned by Georgia Power, Oglethorpe Power, MEAG Power and Dalton Utilities, and is operated by Southern Nuclear. GNF is a GE-led joint venture with Hitachi and operates primarily through Global Nuclear Fuel-Americas in Wilmington, North Carolina, and Global Nuclear Fuel-Japan Co, in Kurihama, Japan.
Southern closed the 876MWe (net) boiling water reactor (BWR) in Georgia on 4 February for a planned refuelling and maintenance outage. In collaboration with GNF, lead test assemblies using an iron-chromium-aluminium fuel cladding material, known as IronClad, and coated zirconium fuel cladding, known as ARMOR, were installed. The reactor resumed operation on 4 March.
GNF said IronClad material is designed to provide oxidation resistance and "excellent material behaviour" over a range of conditions, with low oxidation rates of at higher temperatures further improving safety limit margin. Two variants of IronClad material were installed at Hatch 1 - one in a fuel rod form but without fuel, and the other in the form of a solid bar segment. The IronClad assemblies were developed through the US Department of Energy's Enhanced Accident-tolerant Fuel programme. ARMOR coating, applied to a standard zirconium fuel rod, provides enhanced protection against debris fretting, and higher resistance to oxidation, than standard zirconium cladding. ARMOR lead test assemblies containing fuelled rods have been installed at Hatch 1.
John Williams, nuclear fuel director at Southern Nuclear, said: "Our top priority is the safety and health of the public and our employees, and this game-changing technology will make plants even safer, resulting in more flexibility in our operations. This is not a small step, but a leap for our industry." In 2019, lead test assemblies of GNF's accident-tolerant fuel are also planned to be installed at Exelon Generation's Clinton power plant.
