The Oseberg South platform in the North Sea. (Photo: Øyvind Hagen)
"This is a good example of how to make smaller discoveries profitable. The project has run according to plan, despite the delayed drilling start due to a rig change," says Halfdan Knudsen, who heads up the fast-track development portfolio in Development and Production Norway (DPN).
"We switched to Songa Delta and this meant that drilling and completion could be implemented faster than originally planned. In fast-track we are always looking for opportunities,"
Halfdan Knudsen, heads up the fast-track development portfolio in DPN.
The fast-track projects consist of tying back adjacent new discoveries to existing field infrastructures. Implementation time for the Stjerne project was 39 months once it became part of Statoil's fast-track portfolio.
Statoil's ambition is to cut this time to an average of 30 months for new fast-track projects when experience from the initial projects is fully available.
Stjerne was discovered in 2009. The field has a four-slot seabed template. Two wells will produce oil and gas, while the other two will inject water into the reservoir for pressure support. So far one of the wells has been drilled.
Below budget
"The project's economy appears to be better than expected. We are more than NOK 500 million below what was foreseen when the investment decision was taken," says Knudsen.
Terje Gunnar Hauge, vice president for Oseberg Operations.
The recoverable reserves, which show an increase based on the results from the first well, is now estimated to 49.2 million barrels of oil equivalent (mmboe). Oil constitutes 20.7 mmboe and gas 24.1 mmboe.
In addition, the project will lead to increased recovery of 4.4 mmboe from the Oseberg Omega North reservoir. The estimate for total production volume, according to the plan for development and operation, is 7,800 barrels of oil equivalent per day.
"The Stjerne project is important for Oseberg South and the total production on Oseberg, both in the short and long term. I would like to give credit to the project organisation, suppliers and Statoil's organisation on Oseberg who have really worked hard and done all they can to complete Stjerne. This cooperation is crucial with a view to making faster deliveries than has been possible," says Terje Gunnar Hauge, vice president for Oseberg operations.
Kjetel Digre, senior vice president for the fast-track and subsea project portfolio in TPD.
Safety first
There has been a lot of activity on Oseberg South. Production drilling was temporarily halted while preparations were made for the Stjerne tie-back.
"We had some bold ambitions and made every effort to ensure that this task affected our other operations as little as possible. Having said that, our top priority was as always to ensure that this work should not be at the expense of safe operations and we therefore took every necessary precaution," says Knudsen.
"We've now succeeded in delivering yet another top quality, fast-track project on schedule and well inside the budget," says Kjetel Digre, senior vice president for the fast-track and subsea project portfolio in Technology, Projects & Drilling (TPD).
"We've worked more than 100,000 offshore hours on Oseberg South without a serious incident, and at a cost level that makes us competitive on a global basis. Nor have there been project changes since the concept phase, and all this has resulted in a major saving for Statoil and the licence holders. This proves that we are doing the right thing with our fast-track and standardisation strategy."