LONDON (Reuters) – A reactor at EDF Energy’s (EDF.PA) Hunterston B nuclear energy plant in Scotland will stay offline for extra security checks after cracks have been found in its core, Britain’s Office for Nuclear Regulation (ONR) mentioned.
Ageing reactors generate simply over 20 % of Britain’s energy however virtually half of this capability, together with Hunterston, is because of go offline by 2025, prompting the government to plan new crops.
ONR was knowledgeable in March about keyway root cracks found throughout deliberate inspections of graphite bricks within the core of Reactor three at Hunterston.
Graphite bricks guarantee reactors could be cooled and hundreds of them are utilized in reactor cores.
“Inspections confirmed the expected presence of new keyway root cracks in the reactor core and also identified these happening at a slightly higher rate than modelled,” EDF Energy mentioned in an announcement.
The reactor has been offline since March and was because of come again on-line this month, however EDF Energy has prolonged the outage till later this yr.
“While Hunterston B Reactor 3 could return to operation from the current outage, it will remain offline while the company works with the regulator to ensure that the longer term safety case reflects the findings of the recent inspections and includes the results obtained from other analysis and modelling,” it mentioned.
Hunterston B in North Ayrshire, Scotland, has been producing electrical energy since 1976. Last yr, it produced sufficient electrical energy for 1.eight million houses.
In 2015, EDF Energy mentioned routine inspections had revealed cracks in a part of the graphite core at a Hunterston B nuclear reactor. It mentioned three of 6,000 bricks had cracked, one thing that had been anticipated to start taking place at that time within the energy station’s life.
Two of EDF Energy’s nuclear energy crops in Britain – Heysham 1 and Hartlepool – have been offline for months in 2014 for inspections after a crack was found on a boiler backbone at Heysham 1.
In Belgium, the regulator ordered manufacturing to be stopped at two nuclear reactors in 2012 after discovering indications of tiny cracks in core tanks.
The cracks turned out to be particles of hydrogen that have been trapped contained in the tanks after they have been made by a Dutch company within the early 1980s.
EDF mentioned it expects Hunterston B’s Reactor three to return to service “before the end of 2018”. EDF Energy’s outage web site exhibits an anticipated return date of Oct. four.
Its Reactor three and Reactor four are each Advanced Gas-cooled Reactors. The outage will cut back its 2018 output by three terawatt hours, the company mentioned.
EDF Energy mentioned the operation of its different UK reactors was not affected.
Reporting by Nina Chestney; Editing by Jason Neely and Mark Potter