Hunterston B Power Station is currently providing no electricity to the nation as both reactors are on shutdown for a double outage.

It was planned to bring the outage for Reactor 4 forward as the expertise was currently on site with the current outage of Reactor 3 during a graphite inspection

A spokeswoman for EDF Energy explained: “We decided, while we have the equipment and resources available following the graphite inspections on Reactor 3, to carry out a short, normal core inspection on Reactor 4, expected to last around 25 days. This will give us the chance to check our evaluations and predictions for the reactor and demonstrates that nuclear safety is the overriding priority in everything we do.”

"We informed the SSG of the decision to carry out the outage in August (letter) and highlighted it again at the September SSG meeting.

"Graphite inspection outages are far more focussed than the larger statutory outages so there has not been much change to the worker profile on site."

Reactor 4 is expected to be brought back online by the end of the month, while Reactor 3, which has been undergoing an outage since March for an investigation into the graphite core, is set to return online before the end of November on a trial basis to evaluate its performance before coming fully online for an extended period.

Academic tests and modelling analysis has helped show how the reactor and its cracked bricks could cope with a major seismic event.

Hunterston supremo Colin Weir told the News that tests will continue but he is content the reactor will go back online on November 17.

When reactors three and four are in full operation, they supply 1.7m people in Scotland with electricity.

The projected closure of Hunterston 'B' is 2023.