The energy firm behind one of the world’s biggest offshore wind farms has scrapped plans to build large electricity plants in the Norfolk countryside.
Vattenfall, which wants to build two wind farms around 50 kilometres off the east Norfolk coast, said today it will use more advanced technology which will mean a cable corridor it hopes to dig across the Norfolk countryside will be narrower. It also means no relay stations will be needed.
The Swedish energy company had put forward two options to transmit the energy from the wind farms to the National Grid, called High Voltage Direct Current (HVDC) and High Voltage Alternative Current (HVAC).
Both involve digging a cable corridor 60km from Happisburgh on the coast to Necton where the cables will connect to the National Grid.
But using HVDC means the width of the cable corridor will be halved from around 100 metres to 45m.
Vattenfall said this would mean it could avoid sensitive sites such as St Mary’s Chapel, Kerdiston and a medieval moat north of Necton.
Under the HVAC option two relay stations around eight metres high and taking up several acres of farmland would have been needed near East Ridlington.
That sparked lots of opposition and Vattenfall was not expected to make a decision on the technology it was going to use until after it got permission for the wind farms in 2019.
But today it announced it would use the HVDC option for both its Vanguard and Boreas wind farms.
The downside to the HVDC technology will mean that taller sub stations will need to be built at Necton where the farms join the National Grid.
But Vattenfall said the HVDC substation would be quieter than the HVAC alternative.
Jenny Smedley, from the Necton Substation Action Group, said: “This is good news for Norfolk, but the worst news for Necton.
“We as a group have never campaigned for HVAC. The reason being that although HVDC is far worse for us, we understood that HVAC would be much worse for many more people.
“Our fight to stop Necton ending up with 70 acres of substations of any kind will continue.”
The energy firm said it chose HVDC because it will be cheaper by the 2020s.
It added HVDC would be “better for local people and the environment”.
The energy company also said today it will use something called long range horizontal direction drilling (HDD) at Happisburgh, where the cables make landfall, which they said would avoid impact on the cliffs and mean no work is needed on the beach.
Residents in Happisburgh have protested at the years of disruption the project will cause, including the possible closure of access to the beach and erosion of the cliffs.
Horizontal drilling will also be used to reduce damage to wildlife sites. Vattenfall said it would mean Paston Way, Knapton Cutting, Marriott’s Way and Wendling Carr will be dug under rather than through, meaning less disruption.
Ruari Lean, Vattenfall’s project manager for the scheme, said: “We have listened very carefully to what local people told us about our plans for Norfolk Vanguard.
“By backing HVDC technology, we will minimise the impact on people and the environment whilst keeping the cost of electricity down for the British consumer.”
Vattenfall will submit final plans for the Vanguard wind farm to the Planning Inspectorate in June 2018.
Its second wind farm, Boreas, which also has a capacity of 1.8GW, and will come after Vanguard in the planning process.
When up and running in the mid-2020s, Vanguard’s 1.8GW capacity will produce enough power a year to meet the equivalent electricity demand of 1.3 million UK households, Vattenfall said.
A second cable corridor will be dug at the same time for 55km from Weybourne to Swardeston for a wind farm called Hornsea Three being built by Danish energy firm called Orsted.
Orsted has not said yet whether it will use HVDC or HVAC technology.
Under the HVAC option a relay station would be needed in the north Norfolk countryside and the cable corridor would be wider.