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Heysham 1 and Hartlepool operational update

11 August, 2014


EDF Energy previously advised that one of the two reactors at Heysham 1 nuclear power station had been shut down on 11 June for refuelling and to allow investigations to take place on one of its eight boiler units. This followed tests which took place during a period of planned maintenance and inspection in 2013. EDF Energy is now issuing an operational update concerning Heysham 1 and its sister station of Hartlepool.

During the Heysham 1 Reactor 1 planned statutory outage in 2013, an unexpected result was found during routine ultrasonic inspection of a boiler spine (see Explanatory Note below). No similar results were seen on the other seven boiler spines subjected to equivalent inspections on Heysham 1 Reactor 1, or during subsequent equivalent inspections of the boiler spines on Heysham 1 Reactor 2 and at Hartlepool (the design of the boilers being unique to Hartlepool and Heysham 1). Heysham 1 Reactor 1 was returned to service early in 2014 on reduced load with the affected boiler quadrant isolated pending further investigations to confirm the source of the unexpected inspection result.

Subsequent more detailed inspections of the affected boiler spine during an outage on Heysham 1 Reactor 1 that commenced in June 2014 have confirmed a defect in the location indicated by the initial findings. Heysham 1 Reactor 1 remains shut down while work continues to characterise the nature of the defect.

Although routine inspections of other boiler spines have not previously indicated any similar defects EDF Energy has taken the conservative decision to shut down Heysham 1 Reactor 2 and Hartlepool Reactors 1 and 2 that are of similar design over the next few days to carry out further inspections in order to satisfy itself and the Regulator that the reactors can be safely returned to service. Until the results of the further inspections are known it is not possible to advise exact return to service dates for these four reactors, however, an initial estimate is that these investigations will take around eight weeks. EDF Energy’s other nuclear power stations are not affected by this issue as they are of a different design.

Heysham 1 Reactor 1 is likely to continue to operate on reduced load when it returns to service until a suitable repair strategy can be implemented.

As a result of these further inspections at Heysham 1 and Hartlepool with an initial estimate of around eight weeks the revised likely maximum theoretical output before unplanned losses for the EDF Energy Nuclear Generation Fleet in respect of the period from the 1 January 2014 to 31 December 2014 inclusive will now be c61TWh.

The Company will give a further update in due course.


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Notes To Editors

Explanatory Note:

Each reactor at Heysham 1 and Hartlepool has eight boiler units. These boiler units are arranged around their associated reactor in four quadrants with each quadrant containing two boiler units. Within each boiler unit are boiler tubes assembled in a coil formation around a central forged metal tube called a boiler spine. The boiler spines support the weight of the tubes around them.

Heysham 1 and Hartlepool power stations are of a unique design in the EDF Energy nuclear fleet and the continued safe operation of our other nuclear power stations is not impacted.

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EDF Energy
EDF Energy is one of the UK’s largest energy companies and the largest producer of low-carbon electricity, producing around one-fifth of the nation's electricity from its nuclear power stations, wind farms, coal and gas power stations and combined heat and power plants. The company supplies gas and electricity to 6 million business and residential customer accounts and is the biggest supplier of electricity by volume in Great Britain.

EDF Energy’s safe and secure operation of its eight existing nuclear power stations at sites across the country makes it the UK’s largest generator of low carbon electricity. EDF Energy is also leading the UK's nuclear renaissance and has published plans to build four new nuclear plants, subject to the right investment framework.

These new plants could generate enough low carbon electricity for about 40% of Britain’s homes. They would make an important contribution to the UK’s future needs for clean, secure and affordable energy. The project is already creating business and job opportunities for British companies and workers.

Through Our Better Energy Ambitions, EDF Energy has developed one of the biggest environmental and social programmes of any British energy company.

In 2014 EDF Energy received seven ‘Big Ticks’ in the Business in the Community (BITC) Responsible Business Awards. In 2013 EDF Energy received the Environmental Leadership for Behavioural Change Award in the national Environment and Energy Awards and was highly commended in the first ever pan European Corporate Social Responsibility Awards scheme for its Sustainable Schools programme – the Pod.

EDF Energy is part of EDF Group, one of Europe’s largest power companies. The company employs around 15,000 people at locations across the UK.

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