Norway's oil and gas authorities face a balancing act over whether to meet future gas sales contracts through producing associated gas from currently operating fields or by developing new gas reserves.
Odd Raustein, manager of field development and operation at Norwegian Petroleum Directorate (NPD), said there may arise conflicts of interests for operators of existing fields and new development prospects.
"Norway has a surfeit of mature gas reserves ready to be developed," said Raustein, "but it may be cheaper to recycle gas from older fields for production at a later date and produce sales gas from new fields."
Norway currently reinjects a total 16 billion cu m/year of gas in producing oil and gas/condensate fields. This amounts to one third of total Norwegian gas production.
NPD expects gas export volumes to rise from 28 billion cu m in 1995 to 54 billion cu m in 2000. Raustein said gas injection is also expected to double in this period, so it will still amount to one third of gas produced.
Injection boosts oil recovery
NPD said gas injection projects in Oseberg and Statfjord fields have been successful and will result in increased oil recovery factors.
Norsk Hydro AS, operator of Oseberg, has had to campaign hard to win a concession to sell any gas from the field, and will begin limited sales in 2000.
"NPD has recommended to the ministry that gas production from some fields should be reduced in favor of water-alternating-gas injection," said Raustein. "Oseberg is a case in point."
Norway's Ministry of Industry & Energy initially approved development of Aasgard gas fields off central Norway in preference to production of Oseberg gas to help open up remote Norwegian Sea finds (OGJ, Oct. 9, 1995, p. 29).
Gas injection status
Nine Norwegian fields currently operate gas injection projects. Raustein said that by 2000 gas injection is expected to take place in 18 fields and will total 35 billion cu m/year.
Gas injection has helped Norway raise its average oil recovery from 34% of reserves in place to 41%. This is reckoned to have added 400 million cu m of oil to the reserves base.
NPD said there is potential to add a further 400 million to 1 billion cu m of oil to Norway's reserves through methods including gas injection.
Raustein said the issue of which new fields will be developed and which gas reserves in existing fields will be reinjected, is the focus of talks by the operators' Gas Negotiating Committee. "The business element will be most important in determining gas injection plans," he said.
Copyright 1996 Oil & Gas Journal. All Rights Reserved.
