US power company Exelon has allocated $4.5m to Assistant professor of nuclear science and engineering Michael Short and collaborators at the Massachusetts Institute of Technology (MIT) as well as to the MIT Nuclear Reactor Laboratory and Westinghouse Electric Company to support research on cladding for in light water reactor (LWR) fuel. Four major problems negatively affect the safe and reliable operation of LWR fuel cladding: fretting and wear from grid-to-rod-fretting and foreign material; the build-up of porous corrosion deposits known as “crud”; hydrogen absorption; and boiling crisis. All four have caused failure of the fuel cladding, leading to radioactive releases into the coolant and costing reactor operators over $1m a day of downtime for repairs.
The MIT project aims to address all four issues by developing a viable solution within three years, consisting of engineered cladding surface coatings and micro/nano-geometric modifications. The team will design a set of coatings and surface modifications for Zircolay-based fuel cladding currently in use.
The three-year development time from lab-scale tests to commercial reactor implementation is unprecedented as the normal process for most new reactor components is between 10 and 15 years. The MIT team will work with fuel vendor Westinghouse Electric Company and electric utility Exelon to test and identify the best coating for commercialisation and use in a commercial US reactor by 2019.