Experiences Gained During the Development of the License Renewal Application for Unit 1 of Paks NPP

Operational license of the four VVER-440/213 units at Paks NPP, Hungary is limited to the design lifetime of 30 years. Extension by an additional 20 years of the original license is one of the main goals of the plant owner. In 2008 a programme for long-term operation (LTO) was developed and submitted to the Hungarian Atomic Energy Authority. The LTO Programme defines the activities for ensuring the extension of the operational lifetime and contains the justification of the safe LTO. The LTO Programme has to be implemented and comprehensive justification of the safe LTO has to be provided in the formal License Renewal Applications unit by unit. This work has been completed by the end of 2011, and the application has been submitted for approval for the Unit 1. The authority review and the approval of the License Renewal Application for Unit 1 should be finished before the expiration of the original design lifetime in 2012. In line with the regulations and supporting the License Renewal Application, a large number of engineering tasks have been performed. In this paper the entire project will be reported. The issues will be discussed, which have been arisen during the development of the application as well as the difficulties generated by the Hungarian technical and regulatory peculiarities will be presented.