Centrica shares hit as EDF warns on shut nuclear power reactors

French energy giant EDF today warned that four nuclear power reactors shut down after a defect was discovered in one of them would not be fully operational until the end of the year, knocking shares in part-owner Centrica.

Power supplied by the reactors at Heysham 1 and Hartlepool, which were shut down last month, accounts for roughly 10% of the UK’s nuclear capacity, enough to supply three million homes.

EDF shut them down after a crack was discovered on a boiler spine, a metal tube that supports the weight of the boiler tubes around the reactor.

Engineers must complete inspections to ensure there are no further defects which could develop into cracks, as well as understanding the cause of the crack found.

They must also design and put in place any modifications needed.

British Gas parent Centrica owns a 20% stake in the stations. Its shares eased 1.8p to 323.4p as it raised its estimate of lost earnings as a result of the shutdown from 0.3p a share to between 0.6p and 0.9p.

EDF said a “phased return to service” was expected to take place between October and December.

The firm is leading a consortium which plans to build the £16 billion Hinkley Point C nuclear plant in Somerset.