Image: Hannu Huovila / TVO

Energy production at Eurajoki’s Olkiluoto 1 reactor has been cut back on Monday due to small volumes of seawater leaking into the nuclear condenser. The plant’s owner, Teollisuuden Voima (TVO), says that it is working to locate the fault.

The task of locating the leak and initiating troubleshooting and repair means that the plant’s output is limited to 300 megawatts. The plant is estimated to return to full production by Tuesday morning.

Not a safety risk

The leakage was found when the nuclear reactor’s electrical conductivity was measured. The leaky condenser block has already been removed from the production process. The leak is said to be quite small, letting in a trickle of some two litres per hour.

The role of the condenser is to cool the steam generated in the nuclear reactor, a process which involves the use of seawater.

According to TVO, it will take around eight hours to repair the fault, and the leak does not pose a safety risk.

The two Olkiluoto reactors -- and a third under construction -- are located on an island near Rauma on Finland's west coast.