Finnish nuclear regulator STUK has approved the overall architecture of the instrumentation and control (I&C) systems for Olkiluoto 3 but has asked for further studies to be completed before final approval.
|Olkiluoto 3 pictured in March 2014 (Image: TVO)
The Olkiluoto 3 EPR is being built for Finland's TVO by an Areva-Siemens consortium under a fixed-price €3 billion ($4 billion) turnkey contract. A press release by Areva said the company "welcomed" STUK's approval as a "new, important step" for the project and expressed its confidence in its I&C technology. However, statements by both STUK and TVO highlighted the additional evidence the regulator has requested.
The additional information centres on the independence of the plant's digital I&C and backup systems: the regulator requires reassurance that the automated systems, which would ensure plant safety in the event of an emergency, do not rely on the same systems that are in use during normal operations.
TVO's Olkiluoto 3 project director Jouni Silvennoinen said that testing of some I&C systems had commenced in parallel with STUK's review of the I&C architecture, but said that the plant supplier still needed to complete work on analyses of all possible I&C failure situations.
Construction of Olkiluoto 3 began in 2005 but has faced many challenges resulting in several revisions to its estimated start-up date. TVO continues to say that it is not able to provide any estimate of the unit's likely start-up date at the current time, adding that the supplier consortium is responsible for the time schedule.
Researched and written
by World Nuclear News