LTO of NPP Borssele

LTO of NPP Borssele

27 October 2021

EPZ Foto

The Borssele Nuclear Power Plant is the only operating NPP in the Netherlands. It started commercial operation in 1973 and is therefore already 48 years in production. Long term operation is currently scheduled until 2034. 

In the late nineties the perspective for Borssele was completely different. According to the original Safety Report the design lifetime was 40 years, with the time limitation based on analyses for RPV embrittlement and fatigue of certain components important to safety. The original operating license had no limitation with regard to end of the plant life.  However, based on a political debate and decision, the license of het plant was changed and limited to operation until 2004, meaning only 30 years of operation.

Uniquely the plant workers organized themselves as a legal person (‘stichting 2004+’ see picture) and set up a lawsuit against the government arguing that there was no legitimate basis for the license change. After about two years of hearings the plant workers won the lawsuit and the license limiting date went out. The government then set up a civil lawsuit against the owners of the plant but that was also lost by the government.

In 2006 an agreement was made between the government and the owners of NPP Borssele to allow but also limit operation of the plant for 6o years in the “Borssele Covenant”.

During the period 2007 – 2013 a comprehensive LTO assessment was performed to  prove safe long term operation for 60 years. The LTO assessment was based on IAEA guidelines on Ageing Management and LTO which at that time had a strong resemblance with the US guidelines on License Renewal from 40 to 60 years of operation. The Dutch regulator reviewed the assessment and also asked for the SALTO Peer Review service from the IAEA. Based on the results of the pre-SALTO peer review in 2009, the LTO assessment was further complemented with parts that were originally not in the scope. The full scope SALTO peer review took place in 2012. In this year the plant also submitted the License Change Application for Long Term Operation. This is written in Dutch an can be found here:

After public hearings and a lawsuit from NGO’s like Greenpeace, a new license was issued by the government. According to this LTO-license the end date of operation is December 31th 2033.


So now Borssele is in the LTO-phase and operating for at least 60 years. Of course there are a lot of challenges. After 48 years of operation, a lot of experienced staff with loads of knowledge has retired from the plant. Although several upgrades have been done there is still equipment which uses old techniques, which is difficult to manage. The plant is improving its programmes on equipment reliability including obsolescence and ageing. To be able to reach all the objectives and requirements Borssele is active in exchanging information with other NPPs and uses the help of IAEA and WANO to improve their performance. In this period also the next Periodic Safety Review is performed looking for opportunities to further improve nuclear safety.

The public opinion about nuclear energy in the Netherlands is far more positive than earlier and the government has raised the question about the possibility of further extending the lifetime of Borssele after 2034. In case further LTO is planned, a subsequent license renewal programme has to be performed and also the legal aspect of the Borssele Covenant has to be solved. And of course a lot of technical issues, including again an LTO assessment.

New-built is thought about by the government in the Netherlands. Although EPZ and NPP Borssele are no stakeholder in this, the Borssele site is probably the most favorable site in the Netherlands for a new NPP.  There is enough space and cooling water and based on the current feedback from the community, most people will be quite happy with the opportunities of a new Nuclear Power Plant in their backyard.