Statoil and its partners have today submitted an amendment to the Plan for Development and Operations (PDO) for the Gullfaks licence to the Ministry of Petroleum and Energy for phase 1 of the Shetland/Lista development.
According to Statoil, phase 1 of the development is expected to add 18 million barrels of oil equivalent, and will help increase the resilience of the area for continued operation of the Gullfaks platforms in the North Sea.
“Targeted efforts are underway to cut costs and increase the profitability of our projects. By utilising the existing infrastructure we manage to recover new resources at a lower cost, thus sustaining profitable production and long-term activities on the Norwegian continental shelf (NCS),” says Ivar Aasheim, senior vice president for field development on the NCS.
The development concept is based on reuse of existing wells (a total of 15) from the Gullfaks platforms, and will not require any new infrastructure. The profitability of the project will thus be very good, Statoil emphasized.
Shetland/Lista has been producing under a test production licence since 2013. The submitted plan defines the more long-term development of these resources. This, however, is only the first phase of the development, which involves depressurisation down to bubble point pressure in the reservoir.
“Gullfaks has been a unique industrial venture. Since first oil in December 1986 the field has produced more than 2.56 billion barrels of oil and exported more than 70 billion standard cubic metres (sm3) of gas,” says Kjetil Hove, senior vice president for Operations West, Development and production Norway.
“The current recovery rate on the main Gullfaks field is 59 percent, and with a productive life towards 2036 our aim is to further increase this rate,” Hove says.
Shetland/Lista will add new valuable barrels. Investment costs are estimated at some NOK 900 million ($114.8 million).
Statoil continues its efforts to realise the next phase based on pressure maintenance, the company has said, adding that this is expected to significantly improve the recovery rate for Shetland/Lista.
The Shetland Group and Lista Formation have with different properties compared with the deeper deposits of the Brent Group, where the main Gullfaks reservoirs are located. The producing interval in Shetland/Lista consists of thin limestone beds that are fractured and thus contribute to good productivity.
Indications of hydrocarbons in the Shetland Group/Lista Formation have long been known, Statoil has said. It added that good productivity was initially established in December 2012 and has been confirmed through perforation in another three existing Gullfaks wells, warranting commercial development of the play.