STAVANGER, Norway (Reuters) - Norway's Equinor <EQNR.OL> has increased its resource estimate for its Johan Sverdrup oilfield, the North Sea's largest discovery in more than three decades, while at the same time cutting the cost of development, the company said on Monday.
The field is now believed to hold between 2.2 billion and 3.2 billion barrels of oil equivalent, up from a previous forecast of between 2.1 billion and 3.1 billion barrels.
The overall cost of developing the field has been cut by some 6 billion Norwegian crowns since February to 127 billion Norwegian crowns ($15 billion), Equinor said, as it presented its investment plans for the field's second phase.
While the first phase of the development is on track to start production in November 2019, the second phase is planned to begin pumping in the fourth quarter of 2022, it said.
The operator and its partners will invest 41 billion Norwegian crowns in the second phase, four billion less than an estimate made in February. It will put 86 billion into the first phase, a reduction of 2 billion crowns.
Since announcing its initial plans for the field in 2015, Equinor has cut the investment cost by more than 80 billion crowns, it said.
Equinor, the operator of the field, holds a 40 percent stake, Lundin Petroleum <LUPE.ST> has 22.6 percent, Petoro 17.36 percent, Aker BP <AKERBP.OL> 11.57 percent and Total <TOTF.PA> 8.44 percent.
($1 = 8.4525 Norwegian crowns)
(Reporting by Nerijus Adomaitis, writing by Terje Solsvik)