Developer Equinor says the extension to the field, with planned start-up in 2022, will increase production from 440,000 barrels of oil per day to 660,000 barrels per day.
Johan Sverdrup is the biggest field development on the Norwegian Continental Shelf since the 1980s – the first phase is nearly 90% completed and production is expected to start this November.
The NOK41 billion (£3.6bn) second development phase will include the construction of a new processing platform, modifications of the riser platform, five subsea systems and preparations for power supply from shore to the Utsira High in 2022.
Emissions reductions from Johan Sverdrup are estimated at more than 620,000 tonnes of CO2 on average per year – equivalent to the emissions from 310,000 cars.
Anders Opedal, Executive Vice President for Technology, Projects and Drilling in Equinor said: “This is a big day for Equinor and the other Johan Sverdrup partners comprising Lundin Norway, Petoro, Aker BP and Total. Johan Sverdrup is a world-class field that will provide value to its owners and society for 50 years ahead with record-low emissions. This truly marks the beginning of the second development phase.”