After several years of delay, the Finnish Radiation and Nuclear Safety Authority (STUK) on 10 April 2014 has approved the Instrumentation and Control (I&C) system for the Olkiluoto-3 (OL3) European Pressurized water Reactor (EPR) under construction in Finland. Teollisuuden Voima Oy, (TVO), the owner of the OL3, welcomed the decision, but pointed out that for final approval of the I&C architecture STUK still requires that AREVA complement the ongoing I&C failure analysis.
The news is one of rare substantial progress in a reactor project that is years behind schedule, whose costs have escalated from the original estimate of “around 3 billion euros” to the current estimate of 8.5 billion euros, and where as a consequence, AREVA and TVO are in dispute at the international court of arbitration over costs. It was recently described by AREVA as “one of the biggest conflicts in the history of the construction sector”.
Reflecting the state of relationship with AREVA, STUK has again reiterated that it not satisfied with AREVA, who have failed to provide a plan for the remaining work or updated schedule for completion. Major work at the site is “currently not progressing as the supplier has not completed the engineering… (and) the plant supplier needs to increase its efficiency and complete the remaining works without delay”.
Concerns over the reliability of the Siemens/AREVA I&C technology has been one of many obstacles to progress at the much troubled reactor.
The I&C system consists of a range of systems which in the EPR are required to automatically take measurements and perform control or protection functions, vital for routine operation and in the event of accidents. The EPR relies on two systems,
- the first system (Téléperm XS platform) is dedicated to the reactor’s automated protective and shutdown functions in the event of an incident and to its return to safe operating conditions, in support of the highest safety-classification functions, and
- the second system (SPPA T2000 platform), which acts as a complement, is designed to run the reactor directly from the control room under safe conditions during normal operation and for management purposes over the long term in the event of an accident.
In 2009, STUK, together with their French counterparts, ASN and the UK’s ONR (formerly HSE) asked AREVA and EDF to provide additional justifications for the technology and examine a different design for the EPR reactor I&C.
In April 2012, ASN reported that EDF had undertaken modifications in the design to improve robustness of the SPPA-T2000 Control System.
Consequently ASN was in a position to approve the safety level of the systems used to manage incident or accident situations and their independence from the control systems used for normal operation of the plant.
Meanwhile, at the OL3 construction site reports have emerged of a further slowing down of construction, a reduction in workforce and employment contracts being allowed to lapse; as for start-up date the reactor will certainly not be operational before 2016, but it appears increasingly likely it will be sometime between 2018 and 2020. The original scheduled start-up date was 2009.