According to Southern Nuclear, during a planned maintenance and refuelling outage, operators transferred samples of the lead test rods to the onsite spent fuel pool and have completed an initial inspection of the fuel to compare it to standard zirconium rods.
GNF’s accident tolerant fuel assemblies are of two types: one uses an iron-chromium-aluminium fuel cladding material known as IronClad and the other – a coated zirconium fuel cladding known as ARMOR.
Southern Nuclear said testing at Hatch included unfuelled IronClad lead test rods and fuelled ARMOR-coated zirconium cladding test rods.
The company said data from the fuel testing will be used by Southern Nuclear and GNF to help future development of accident-tolerant fuel technologies and provide information to the US Nuclear Regulatory Commission licensing review process.
Southern Nuclear said Oak Ridge National Lab will conduct further evaluations of the lead test rods’ material and coating properties.
In 2018, GNF loaded IronClad and ARMOR test rods at the Hatch plant, while last month lead test assemblies were loaded at Exelon’s single-unit Clinton nuclear power station in Illinois.
According to GNF, the IronClad and ARMOR technologies are designed to provide oxidation resistance and superior material behaviour over a range of conditions compared to existing options. The ARMOR-coated zirconium cladding also provides improved protection of fuel rods against debris fretting.
General Electric, which leads the GNF joint venture with Hitachi, was awarded in 2018 a $33.7m project from the US Department of Energy to continue development of advanced nuclear fuel rod technologies that are more robust and have improved performance during normal and accident conditions, the company said yesterday.
The goal over the two-and-a-half-year project is to develop and demonstrate new fuel rods that could be commercially deployed and set new standards in nuclear plant safety.
Southern Nuclear said the nuclear industry is pursuing the licensing and full commercial deployment of accident-tolerant fuel by the mid-2020s.