UPDATE 1-EDF Energy could bring forward decommissioning of Dungeness B nuclear plant

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LONDON, April 8 (Reuters) - EDF Energy, owned by French utility EDF, is exploring a range of scenarios for its Dungeness B nuclear plant in Britain, including bringing forward its decommissioning date of 2028, it said on Thursday.

The phasing out of ageing nuclear and coal-fired power plants, combined with declining North Sea oil and gas output, is putting pressure on Britain to develop new sources of energy and build new nuclear plants, something it has not done in around three decades.

The 1.1 gigawatt Dungeness B plant, in Kent on the south coast of England, has been offline since 2018 as the company has been carrying out inspections and maintenance of pipes carrying steam to the turbine.

EDF Energy has also been trying to complete repair work on corrosion identified during inspections of safety back-up systems.

The plant is currently forecast to return to service in August. It was designed in the 1960s and first started generating electricity in 1983.

EDF Energy said it has spent more than 100 million pounds ($138 million) on the plant during its current outage and it has a number of ongoing technical challenges that make its future uncertain.

The plant is scheduled to be decommissioned in 2028.

However, a range of options is being explored, such as moving directly into the defuelling phase later this year, if it cannot return to service as planned this August.

EDF Energy said it could also decide to bring forward its end of generation date or continue the plant’s operation until the scheduled decommissioning date.

The company said it expects to make a decision on the plant in the next few months.

Last year, EDF Energy said it would close its Hinkley Point B and Hunterston B nuclear plants earlier than planned. They are scheduled to close in 2022 and 2021 respectively. ($1 = 0.7265 pounds) (Reporting by Nina Chestney Editing by David Goodman and David Evans)