© The Financial Times Ltd 2015 FT and 'Financial Times' are trademarks of The Financial Times Ltd.
Last updated: August 11, 2014 2:38 pm
EDF Energy has shut down four of its UK reactors – a quarter of its total nuclear generating capacity – after discovering a fault in a boiler unit, in a move that highlights the challenges facing Britain’s ageing energy infrastructure.
The company said on Monday it had found a defect on a boiler spine at a reactor at its Heysham-1 plant in Lancashire, and shut it down in June. It said it then took the “conservative decision” to halt the second reactor at Heysham-1 and two at its Hartlepool site in the northeast of England which are of a similar design. The units are expected to remain closed for eight weeks.
The UK subsidiary of French state-owned utility EDF owns and operates 15 nuclear reactors in Britain with a combined electricity generation capacity of about 8.8m kilowatts – more than 10 per cent of the UK total.
As a result of the shutdowns, EDF now expects to generate about 61 terawatt-hours of electricity from its reactors this year, compared with the 63.9 TWh it estimated last month – a 4.5 per cent drop.
But National Grid said the closures should not affect the UK’s energy supply. “Demand is low at this time of year, and a lot of wind power is being generated right now,” it said.
The UK’s fleet of nuclear plants has become increasingly prone to operational problems as the reactors, many of which were built in the 1980s, approach the end of their service life. Heysham-1 and Hartlepool were both commissioned in 1983 and are due to come out of service in 2019.
The UK government has been pursuing plans for a new generation of nuclear plants, but no new reactors are expected to come on line until well into the next decade.
EDF Energy intends to build a £16bn power station at Hinkley Point C in Somerset, which will be Britain’s first new nuclear plant in a generation. But the project is on hold pending a decision by Brussels as to whether the investment contract agreed between EDF and the government constitutes legal state aid.
Meanwhile, the company has been seeking life extensions for its existing fleet of plants, most of which are scheduled to close by the end of 2023. The latest is Dungeness B in Kent: EDF wants to extend its life by 10 years to 2028, with a decision expected this year.
EDF said that during a planned outage at Reactor 1 at its Heysham-1 plant, an “unexpected result” was found during a routine inspection of a boiler unit. The reactor was returned to service early this year on a reduced load, with the affected part of the boiler isolated pending further tests.
More detailed inspections during an outage that started in June confirmed a defect and the reactor remains shut down.
But EDF Energy said it had decided to shut down three other reactors that are of similar design to the affected plant as a precaution. The closures will allow the company “to carry out further inspections in order to satisfy itself and the regulator that the reactors can be safely returned to service”, it said.
The boiler spine, where the defect at Heysham-1 was found, is a central forged metal tube that supports the weight of the boiler tubes around them.
Joe Conlan, an analyst at energy consultancy Inenco, said it was not uncommon for four reactors to be offline at the same time, but “for all four to be turned off simultaneously is highly unusual”. He said there would have been a real threat of blackouts if the shutdowns had occurred “during the energy-intensive winter months”.
Centrica, the owner of British Gas which has a 20 per cent stake in EDF Energy’s existing nuclear operations, said the reduction in output from the affected nuclear power stations would reduce the company’s 2014 earnings by roughly 0.3p per share.
EDF Energy’s nuclear plants are at Torness in Dunbar and Hunterston B in West Kilbride, Scotland; Sizewell B in Suffolk; Hinkley Point B in Somerset, Heysham 1 and 2 in Lancashire; Hartlepool; and Dungeness in Kent.
Copyright The Financial Times Limited 2015. You may share using our article tools.
Please don't cut articles from FT.com and redistribute by email or post to the web.
Sign up for email briefings to stay up to date on topics you are interested in