GE has secured a £1.5bn ($1.9bn) contract to supply two power islands for the Hinkley Point C nuclear plant.
The company will build the two islands, which will include two 1.7 GW Arabelle steam turbines and other critical infrastructure.
The power islands are part of the plant, which converts the steam created on the nuclear island into electricity.
The approval of the contract comes days after the UK government gave the green light to the £18bn Somerset nuclear power station.
Alstom Power & Grid was named preferred bidder for the contract in October 2013 but the business was bought by GE last November.
The acquisition saw GE secure the rights to the Arabelle turbine, which is the biggest of its kind in the world.
Two-thirds of UK’s existing nuclear power stations were built with steam turbines manufactured by Alstom and its predecessor companies.
GE has been working with EDF for over six months under an early contractor involvement agreement, which includes activities such as safety classification, planning, civil works interfaces, pre-engineering and procurement planning.
The approval of the decision means GE can now ramp up its procurement activity with suppliers, a large percentage of which will be UK-based.
GE Power president and CEO Steve Bolze said: “With the acquisition of Alstom Power & Grid we’re now able to offer a broader portfolio of technology solutions that provide reliable and efficient power for our customers.
“We are pleased to be working with EDF Energy on Hinkley Point C to help deliver on the UK government’s vision for energy security and economic development.”