OSLO, Norway– The Norwegian Petroleum Directorate’s latest Norwegian Continental Shelf publication predicts an investment decision later this year on the Snorre Expansion project in the North Sea.
Statoil and its partners are due to submit a plan for development and operation (PDO) which calls for installation of six or seven large subsea templates providing up to 28 new well slots.
“That could allow Snorre to stay onstream until well after 2040 – 30 years beyond the original PDO forecast,” said Tomas Mørch, NPD’s assistant director for development and operations.
“Resource extraction will increase by at least about 190 MMbbl…equivalent to a Goliat field.”
Statoil has analyzed various solutions for improved recovery from the field, which lies 2,000-2,500 m (6,561-8,202 ft) beneath the seabed. The reservoir comprises Jurassic and Triassic riverine deposits from around 200 million years ago, and covers an area of 10 x 25 km (6.2 x 15.5 mi).
Originally, Snorre was expected to be shut down three-four years ago. The reservoir is complex, and has had three different operators since production started 1992 – Saga Petroleum, Norsk Hydro, and now Statoil.
The original PDO assessed recoverable oil at almost 750 MMbbl. Continued drilling of new wells has helped lift that figure to just over 1.7 Bbbl, and the PDO later this year should raise the total above 1.9 Bbbl.
Saga’s initial PDO anticipated that production would cease in 2012-14, but learnings over the years and adoption of improved techniques, combined with greater familiarity with subsurface issues, have led Statoil to identify new opportunities.
The first-phase development was based on a TLP tied to a subsea template, with a semisubmersible platform coming onstream under a second phase in 2001.
In 2010-11, Statoil proposed installing a new subsea template in the north, but the government felt a larger solution would be needed. This led to selection of a Snorre C platform as a third concept in 2013 under theSnorre 2040 project, but as costs rose and oil prices fell back, Statoil was forced to rethink its plans.
However, late last year the licensees resolved to continue the project under the new name of Snorre Expansion. They dropped the platform concept in favor of six or seven templates tied back to Snorre A, providing capacity for up to 28 new wells.
Originally, plans called for 93 wells, but to date more than 120 production and injection wells have been drilled.
The latest temporary license extension expires in June 2018, and a new PDO must be approved by then. If this happens, the two licenses covering Snorre will be extended further.