More retrofits for Olkiluoto 1 and 2

Wednesday, 6 June 2007 Olkiluoto units 1 and 2 will receive new low-pressure steam turbines under a Eur100 million ($135 million) deal signed by owner Teollisuuden Voima Oy (TVO) and Alstom. Unit 1 will also receive a new generator.

TVO said that the work is part of its long-term development plan for the units, which are boiling water reactors built by Sweden's ABB Atom at the end of the 1970s. Originally rated at 690 MWe each, the power plants have undergone several technical improvements over the years to reach outputs of 870 MWe each, and increase their operational periods to 60 years. Between them they provide about 12% of Finland's electricity.

A TVO statement said the company's aim was to "minimise risks of operational unreliability and simultaneously to take advantage of advanced turbine technology." Modern materials and methods have made it possible to replace original hi-tech components like turbines with more efficient versions while re-using existing steam pipework and casings.

A steam turbine retrofit project can increase output by up to around 3% - TVO said the work would result in a 1% improvement in the units' overall thermal efficiency and increase their combined electrical output by 25 MWe (1.4%). Changes would be necessary to instrumention and control systems for the turbines, but the rest of the plant would not be affected.

Alstom's Swedish business will carry out the contract, which covers new rotors and blades, during the units' 2010 and 2011 annual service outages.

In addition to the turbines, Olkiluoto 1 would receive a new generator. It will match the Eur20 million ($27 million) model Alstom are already contracted to install at unit 2 in 2009. Alstom also provided a retrofit of high-pressure turbines and moisture separator reheaters for both Olkiluoto units in 2005 and 2006 under a Eur35 million ($47 million) deal.

Further information

Alstom
Teollisuuden Voima Oy (TVO)

WNA's Nuclear Energy in Finland information paper