One of Heysham 2 nuclear power station's reactors was offline during the Christmas period due to a fault.
The outage on Monday December 23 was caused by an issue with the high voltage transmission system run by National Grid, EDF Energy confirmed.
EDF said it worked with National Grid over the Christmas period to fix the issue and safely return the reactor to service
They said the Office for Nuclear Regulation was kept fully informed during the incident.
“On Monday 23rd December, one of the units at Heysham 2 power station came offline following a fault on the high voltage transmission system, which is remote to the site and owned and operated by the National Grid," said an EDF spokesperson.
“Teams from EDF and the National Grid worked over the Christmas period to rectify the issue and safely return the reactor to service. Our regulators the Office for Nuclear Regulation (ONR) have been kept fully informed.”
Heysham 2’s second reactor and one of the reactors at Heysham 1 remained at full power during the outage.
Heysham 1’s second reactor was already offline for planned maintenance.
The National Grid has confirmed there was a fault at a National Grid substation remote to Heysham, coincident with Heysham 2 tripping.
EDF recently announced that Heysham 2 will extend its life to 2030, an extra two years. The plant began generating power in 1988.
Heysham 1, which began operating in 1983, will extend to 2027.
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