The development of the Åsgard subsea gas compression was approved in the Storting (Norwegian parliament) on 27 March 2012. This signals the start for implementation of one of Statoil’s most demanding technology projects aimed at improving recovery.
Åsgard subsea gas compression will increase recovery from Mikkel and Midgard by around 280 million barrels of oil equivalents, or as much as the entire Snorre field. The technology represents a quantum leap that can contribute to significant improvements in both recovery rate and lifetime for a number of gas fields.
“Åsgard subsea gas compression is a profitable and robust project. Development of the world’s first compression facility for gas under water is a challenging task,” says Astrid Jørgenvåg, production director for the Åsgard area. “As time passes, the pressure from Midgard and Mikkel will be too low to maintain stable flow and high production to the Åsgard B platform. To compensate for this, we will install compressors on the seabed near the wellhead to increase pressure in the production flowlines.
Prior to the approval of the Plan for Development and Operation (PDO), Statoil notified the authorities of a cost increase in the project.
Preliminary assessments show that the growth lies within the range of uncertainty of about 20 per cent of the total investment amount set last summer. There are two main issues that have impacted the cost scenario. One is a tighter supplier market within marine operations. Rates have gone up, particularly within the installation segment in the period after we submitted the PDO last year. The other factor is changes made during the design work to ensure high regularity, maximum recovery and even more robust production. These changes have lead to certain design modifications and weight increases on modules.
“The higher costs we are now seeing are unfortunate. They show the complexity of such a pioneering project as Åsgard subsea gas compression. We are working hard to reduce costs while safeguarding quality,” says Anders Opedal, who leads the project in Technology, projects and drilling (TPD).
Project progressing on schedule
All of the major contracts in the Åsgard subsea compression project have already been awarded, and most of the detailed engineering is complete. This spring Statoil will also start assembly of modules at Aker Solutions’ yard in Egersund. According to plan, Åsgard subsea gas compression will be ready for start-up in the first half of 2015. For the most part, the project will be the first user of technology never before applied under comparable conditions. For this reason, a very extensive and thorough qualification program has been implemented for the new technology, including a program for continuation with realistic sea tests at our test facilities at Kårstø, K-lab, during the course of the year. So far, the tests are showing good results.
“Subsea gas compression is an important step on the road towards our ambition of installing the elements for a subsea plant by 2020. Processing on the seabed could open up areas that are not currently accessible with traditional technology,” says Opedal.
Partners on the Åsgard field: Petoro AS (35.69 per cent), Statoil (operator) (34.57), Eni Norge AS (14.82), Total E&P Norge AS (7.68) and ExxonMobil Development Norway (7.24).
Source: Statoil, March 27, 2012