Four nuclear reactors at Heysham 1 and Hartlepool nuclear power stations, which provide around 2,350 megawatts of electricity generation in the UK, have been returned to service following a 17-month outage.
Reactor 2 at Heysham 1 power station, the last of the four reactors to return to service, began supplying power to the grid on 17 March.
The four reactors were taken out of service in October 2007 after a planned inspection revealed some corrosion on wires which are part of the boiler closure units. Following a 17-month programme encompassing more than three million man hours of work the four reactors have been returned to service. The first three units are operating at full load and the fourth reactor is being increased to full load in a planned power increase.
Whilst the reactors were out of service, British Energy took the opportunity to bring forward maintenance work, including the replacement of a generator stator and main generator transformer at Hartlepool and the replacement of some 3km of cast iron cooling water pipe work at both stations.
Gwen Parry-Jones, station director at Heysham 1, said: "Now the BCU programme is complete, reactor 2 is supplying power to the grid and will gradually be brought back to full power over the coming days. The start-up is not routine as the unit has been out of service for almost one and a half years and a robust recommissioning programme was developed to return the unit to full power and address any equipment issues that may arise in the process."
EDF Energy acquired British Energy in January 2009 and plans to build four new reactors with the first operational by the end of 2017, while investing in its existing eight nuclear power stations which provide the UK with about one sixth of its electricity.