New operation date for Olkiluoto 3

11 January 2007

Efforts to reduce early construction delays have not stopped Olkiluoto 3's completion date slipping to the end of 2010.

Since construction began in the spring of 2005, a number of problems have beset Teosulliden Voimy Oy's (TVO's) project to build a European Pressurized Water Reactor (EPR) at the Olkiluoto site in Finland. Originally, the new unit – the first to be ordered in Western Europe for 15 years – was scheduled to begin commercial operation in 2009, but 19 months into the project, delays have pushed that date has back by over a year.

The most significant delay has concerned non-conformity of the concrete used in the new unit's foundations. A higher than expected water content was detected in some lots and, although there was no question that the concrete would not perform safely, the Finnish safety authority, STUK, ordered concreting work to stop while the source of the excess water was found. Later, sections of the reactor's pressurizer had to be re-cast after the forging supplier failed to ensure high enough quality. Now, it has been discovered that three of the reactor's four main coolant lines need to have some of their forgings recast.

Observers suggest that the problems faced in building Olkiluoto 3 are only to be expected, given that most of the subcontractors involved have not worked to nuclear standards for many years if at all, and that lessons are being learned from these problems at TVO, Areva, Siemens, their subcontractors and STUK. Nevertheless, a TVO statement read: "TVO is not satisfied with the time schedule situation."

About 1000 construction workers are currently involved in the project which will see a 1600 MWe EPR stand alongside two existing boiling water reactors (840 and 860 MWe). A turnkey contract was signed in December 2003 for a consortium of France's Areva and Germany's Siemens to build the plant for TVO. It is expected that the EPR will be the standard design for the next generation of French reactor, and construction of an EPR at Flamanville in France's Manche region should begin in 2007.

Further information

Siemens Power Generation
Teosulliden Voima Oy, TVO