Poolside Inspections of Spent Nuclear Fuel at Loviisa NPP
26th Symposium of AER on VVER Reactor Physics and Reactor Safety (2016, Helsinki, Finland)
Fuel behavior in normal conditions
Abstract
POOLSIDE INSPECTIONS OF SPENT NUCLEAR FUEL AT LOVIISA NPPIiro-Ville Lehtinen Fortum Power and Heat OyABSTRACTLoviisa NPP has a long history of poolside inspections of spent nuclear fuel starting from the middle of the 80’s. These inspections are usually performed at the spent nuclear fuel interim storage building after one to two years cooling period. The inspection equipment can be moved to the reactor building well also, if it is required to perform inspections right after the removal of the fuel from the core. Loviisa NPP uses own inspection equipment originally developed by IVO Engineering (now part of Fortum).The results of the poolside inspections are used to verify fuel performance in normal operating conditions and during interim storage, but also to evaluate the effects of fuel design changes and to find root causes of fuel failures. Furthermore, the results have been used together with reactor physics and fuel performance codes to improve the fuel economy and to verify safety analysis input parameters.In this paper Loviisa NPP poolside inspection equipment and methods are introduced together with a short summary of the current inspection programs. A summary of inspection results is also given. In addition, some examples are presented on how the poolside inspection results have helped Loviisa NPP to better understand fuel performance, reduce fuel failures and improve fuel economy.Keywords: VVER-440, fuel performance, operational experience, poolside inspections26th Symposium of AER on VVER Reactor Physics and Reactor Safety 50 10 – 14 October 2016, Helsinki, Finland