Swedish energy firm Vattenfall is selling the subsea cables connecting Thanet offshore wind farm with the Kent coast to Balfour Beatty.
The British infrastructure group is paying £164 million for the electricity cables and substations linked to the 100-turbine wind farm.
Vattenfall still owns the wind farm itself.
Piers Guy, Vattenfall’s UK Country Manager said: “[Our] offshore wind business has strong foundations in the UK and we are keen to build on the three wind farms we currently have in operation in UK waters.
“The completion of this complex deal helps us to put more effort into strengthening our UK wind energy business.”
Thanet first put electricity into the grid in 2010.