ESSANUF - European Supply of SAfe NUclear Fuel

Westinghouse successfully supplied VVER-440 fuel assemblies to Loviisa (Finland) from 2001 to 2007. After losing two bids in 2007, Westinghouse decided to close down the supply chain and design development for the VVER-440 design. Since September of 2015, Westinghouse and eight European consortium partners are in a project; ESSANUF (European Supply of SAfe NUclear Fuel), with the objective to diversify the nuclear fuel supply to Russian designed VVER-440 reactors operating in Europe. The program is funded by the European Union's (EU's) Euratom Research and Training Programme under Horizon 2020. Design upgrades of the Westinghouse VVER-440 designs have been evaluated with respect to their feasibility for future use. Material development, operational experience, customer feedback and competitor design modifications have been considered and a conceptual design has been developed which contains an upgraded spacer grid which benefits from design features from Westinghouse VVER-1000 fuel design. In addition materials are proposed to be upgraded using the latest experience from Westinghouse VVER, PWR and BWR programs. Based on review feedback from a concepts and issues review of the proposed VVER-440 conceptual design Westinghouse recognizes the importance of a longer pellet stack and will continue to evaluate necessary top- and/or bottom nozzle modifications to enable a longer fuel rod. A scope description and a high level milestone schedule for a development program with a goal to implement the proposed changes within two years have been outlined within the ESSANUF project. To support the introduction of the upgraded VVER-440 fuel design methods and methodologies within the technology areas nuclear-, fuel rod- and thermal hydraulic design as well as criticality- and fault analyses have been evaluated. The approach used was to select and validate the most suited set of codes by inventing what codes are used in the different countries with VVER-440 reactors and thereafter define the methodologies to be applied. To enable effective analyses it is important to have well defined and preferably auto ESSANUF - European Supply of SAfe NUclear Fuel J Höglund, S. Kristensson Westinghouse Sweden, Västerås, Sweden mated interfaces between the codes for the transfer of data and results. To achieve this different forms and code couplings have been developed. An attempt to develop a generic fuel licensing approach for the countries that are using Russian design VVER-440 type reactors has been carried out in ESSANUF. The concept is to limit the number of events to be re-analyzed by considering them covered by more limiting events. Also a generic Interface Document for Fuel Licensing (IDFL) has been suggested. Two project review meetings with independent experts empowered by the European Commission have been carried out to evaluate project progress and fulfillment of project commitments with satisfactory results. The ESSANUF project ends in October 2017.