The French energy giant said that while “significant progress” was made on the Somerset site last year, the project was affected by the Covid-19 pandemic.

It has forced a number of changes on the Hinkley site, including reducing the number of workers to enable social distancing and concentrating on the most critical areas of construction.

It now expects the station to start generating electricity from Unit 1 in June 2026, compared to the end of 2025 as initially announced in 2016. The project is currently focusing on lifting the Unit 1 dome by the end of next year.

The total projected cost has also risen to between £22-23bn – another significant increase on original estimates of between £21.5bn and £22.5bn.

This isn’t the first time that the UK’s first nuclear power plant in a generation has faced setbacks. In 2017, EDF raised its estimated cost by £1.5bn above the original total of £18bn and delayed its final construction.

Once completed, Hinkley Point C is expected to be able to generate enough electricity to power around six million UK homes.

EDF said the delay and increased costs mean the expected rate of return from its investment will fall from between 7.6 and 7.8 per cent to between 7.1 and 7.2 per cent.

The Hinkley site reached a major milestone last summer, with EDF completing the 49,000-tonne base for the second reactor on schedule, less than a year after completion of the first reactor’s base in June 2019.

Last year, EDF submitted an application to to build Sizewell C, a new nuclear power station in Suffolk, that will be able to generate around 3.2GW of electricity. The plans for the plant are a near-replication of those submitted for Hinkley Point C, which EDF has suggested could help to reduce construction costs and risk.

The French energy giant said that while “significant progress” was made on the Somerset site last year, the project was affected by the Covid-19 pandemic.

It has forced a number of changes on the Hinkley site, including reducing the number of workers to enable social distancing and concentrating on the most critical areas of construction.

It now expects the station to start generating electricity from Unit 1 in June 2026, compared to the end of 2025 as initially announced in 2016. The project is currently focusing on lifting the Unit 1 dome by the end of next year.

The total projected cost has also risen to between £22-23bn – another significant increase on original estimates of between £21.5bn and £22.5bn.

This isn’t the first time that the UK’s first nuclear power plant in a generation has faced setbacks. In 2017, EDF raised its estimated cost by £1.5bn above the original total of £18bn and delayed its final construction.

Once completed, Hinkley Point C is expected to be able to generate enough electricity to power around six million UK homes.

EDF said the delay and increased costs mean the expected rate of return from its investment will fall from between 7.6 and 7.8 per cent to between 7.1 and 7.2 per cent.

The Hinkley site reached a major milestone last summer, with EDF completing the 49,000-tonne base for the second reactor on schedule, less than a year after completion of the first reactor’s base in June 2019.

Last year, EDF submitted an application to to build Sizewell C, a new nuclear power station in Suffolk, that will be able to generate around 3.2GW of electricity. The plans for the plant are a near-replication of those submitted for Hinkley Point C, which EDF has suggested could help to reduce construction costs and risk.