ABB has been awarded a $450 million (£288m) contract to link the power grids of the UK and Norway.
The company aims to increase security of supply for both countries and support the integration of wind and hydroelectric power into their networks.
The UK-Norway Interconnector (NSN), which is expected to be 730 kilometres long and have a capacity of 1.4GW, is owned by National Grid and Norwegian transmission system operator Statnett.
ABB will supply high-voltage direct current (HVDC) converter stations at both ends of the North Sea.
Claudio Facchin, President of ABB Power Systems division said: “HVDC is a proven solution for the integration of renewables and the reliable and efficient long distance transmission of power, often subsea or underground.”
The interconnector, which is said to be the world’s longest subsea power link, is scheduled to be completed in 2021.