French utility EDF shut down two nuclear plants that it operates in the UK after routine inspections uncovered possible defects in one reactor. The two power plants, both with two units, are of the same design, and shutdowns were ordered for the other three reactors as a safety precaution.
The affected plants are Heysham 1 in Lancashire and Hartlepool, both 1,190-MW advanced gas-cooled models that came online in 1980 and 1985, respectively. Each reactor uses a four-loop design, with two steam generators per loop. During a routine inspection in 2013, a defect was discovered in a tube support element in one boiler at Heysham 1. Though the unit was returned to service with that loop isolated, a follow-up inspection this spring confirmed the problem, and the reactor was shut down as a precautionary measure. EDF then decided to shut down the other three reactors as well so they could be fully inspected.
EDF said in a statement that the plants would be offline for about eight weeks. Further work is underway to fully characterize the defect and determine next steps. “Until the results of the further inspections are known it is not possible to advise exact return to service dates for these four reactors,” it said.
The two nuclear plants are of a unique design in the EDF fleet, and no other reactors are affected by the problem.
—Thomas W. Overton is a POWER associate editor.