Plans to massively expand two wind farms off the north Norfolk coast have taken a step forward.

Equinor, the Norwegian state-owned energy giant, has asked the Planning Inspectorate for the green light to double the size of its Dudgeon and Sheringham Shoal wind farms.

Kari-Hege Mork, Equinor's project director, said it was a "significant milestone" for the project, which was already three years in the making.

North Norfolk News: The proposed expansion areas of Equinor's Sheringham Shoal and Dudgeon wind farms off the north Norfolk coastThe proposed expansion areas of Equinor's Sheringham Shoal and Dudgeon wind farms off the north Norfolk coast (Image: Equinor)

She said: "It is also a milestone for the offshore wind industry, as it is the first time two offshore wind farms in the UK are being proposed with an integrated transmission system, including a single point of connection to shore."

Sheringham Shoal is around 17kms (10 miles) off Weybourne at its nearest point to shore.

Together they consist of 155 turbines, and although 95 are planned for the expansion, the new ones will be much bigger - taller than the Eiffel Tower at 330m.

The expansion means the wind farms could power 1.5 million homes.

North Norfolk News: The proposed cable trench area from Weybourne to the Norwich Main Substation at Stoke Holy CrossThe proposed cable trench area from Weybourne to the Norwich Main Substation at Stoke Holy Cross (Image: Equinor)

Connecting cables will be laid across the sea floor to Weybourne, and then a further 60kms (37 miles) in an underground trench to a new substation near the Norwich Main Substation at Stoke Holy Cross, south of the city.

But there are concerns over the expansion's impact.

In a consultation late last year, 16.9pc of responses raised fears over traffic and access during construction; followed by ecology (14.9pc); visual impact (13.8pc) and noise and vibration from construction (13.4pc).

The government has called the expansion a 'pathfinder' project in an on-going Offshore Transmission Network Review.

It is hoped this could lead to better co-ordination of offshore projects, meaning new trenches would not have to be dug across the Norfolk countryside to connect each new wind farm to the National Grid.

Dan McGrail, chief executive of industry lobby group Renewable UK, said: "This first Pathfinder project is an important step in upgrading the grid so that we can provide cheap renewable power to consumers."

The Inspectorate has 28 days to decide whether Equinor's Development Consent Order submission should be accepted, and if it agrees there will be a further consultation.