As oil prices top the US$100 a barrel mark, five-month old Taranaki oil field Tui has ramped up production to just below its forecast peak of 50,000 barrels a day.
Following modifications in November, production rates rose to an average of more than 48,000 barrels a day for December, or 1.5 million barrels for the month.
The oil is benchmarked against a regional crude, Tapis, which averaged around US$95 ($124) a barrel in December.
That valued the monthly output at around $186 million.
The field, 60km off the Taranaki coast, had produced about 6.4 million barrels of oil since the end of July and contains an estimated 41.7 million barrels of proved and probable reserves.
The oil is shipped to refineries on the east coast of Australia or in southeast Asia.
Estimated production for the 2007/08 year was increased to at least 11 million barrels from 10 million.
Tui partners are AWE, the operator with 42.5 per cent, Mitsui with 35 per cent, Pan Pacific Petroleum with 10 per cent and NZ Oil and Gas with 12.5 per cent.
