Statfjord: Norway’s drive to maximise recovery rates from her mature fields In the oil and gas industry today, 70 per cent of the world's oil reserves are located in mature fields – assets where production has reached its peak and has started to decline. As things stand that accounts for in excess of 63 million barrels-worth of oil production per day. Nowhere are the challenges presented by mature fields more acutely felt than on the Norwegian Continental Shelf (NCS), where the majority of the 69 fields in production today are classified as mature. In 2001, production on the NCS reached a peak of 3.4 million barrels per day. As of January 2013, Norwegian assets were producing only 1.4 million barrels of oil per day – roughly a 5 per cent year-on-year decrease over a 12 year period. Oil hunger Norway is reliant on and addicted to oil. The marginal tax rate on net profits within the petroleum sector is 78 per cent and in 2012, 30 per cent of total State revenue was derived from the hydrocarbon industry. In Q2 2013, crude oil and natural gas accounted for 41 per cent of all Norwegian exports and 35 per cent of the growth in Norway’s economy could be directly attributed to oil activity. The country’s oil fund is the world’s largest at NOK 4.52 trillion ($750 billion) and is set to grow by a further 50 per cent by 2020. The oil and gas industry dwarfs every other sector in the national economy. Moves are being made to wean the country off of its oil craving with tax cuts to bolster other industry sectors. That said, the prosperity of this 5 million-strong Scandinavian nation will always be largely linked to its ability to exploit hydrocarbons. That is where enhanced oil recovery – the range of techniques used to extract every last drop of crude oil from an oil field - comes into its own on the NCS, and how the Statfjord Late Life Project (SFLL) is a microcosm of Norway’s economic future. The Statfjord Story The Statfjord oil field holds the record for the highest daily production ever recorded for a European oil field outside of the Russian Federation. 26 years after peak production was achieved, the three condeep concrete production platforms, A, B and C are producing 8000 times less oil than in their heyday. With more than 60 per cent of the oil in place already produced and the end of the field’s commercially-viable life in sight, Statoil initiated the SFLL in 2005 to extend production of the well to 2019 to squeeze a further eight per cent out of declining reserves. From oil to gas Statfjord is currently an oil field with associated gas - the late life project will transform it into a gas field with associated oil. The main aim of the project is to reduce pressure in the reservoirs and on the three platforms to make possible the recovery of large volumes of gas (injected into the well during secondary oil recovery) whilst simultaneously liberating gas from the remaining unrecoverable oil. This methodology will increase the gas recovery factor by 21 per cent to almost 75 per cent. The SFLL plan is comprised of three pillars: . Drilling and recompletion of 70 new oil, water and gas wells. At the beginning of 2013 50 of these were completed. Modifying platforms to handle larger volumes of gas under lower pressure . Installation of the 23.1 kilometre Tampen Link pipeline between Statfjord and Britain’s Far North Liquids and Associated Gas System (FLAGS) to carry gas to St Fergus in Scotland. This was completed in Q4 2007. Giving this new lease of life to a field does not come without its price though. As of the beginning of 2012, NOK 65.3 billion ($10.9 billion) had been spent on the project with a further spend of NOK 9.7 billion ($1.6 billion) still planned in the coming years. EOR on the NCS In the words of the incumbent Norwegian Minister of Petroleum and Energy, Ola Borten- Moe: “We know that one of the biggest challenges we have on the Norwegian Shelf going forward is to manage the resources we already have in a better way, that is, to get more out of existing fields. Therein lies the greatest value and the greatest challenge.” According to the latest estimates from the Norwegian Petroleum Directorate (NPD), the total discovered and undiscovered petroleum resources on the Norwegian Continental Shelf amount to approximately 13.6 billion Sm³ (85.5 billion barrels). Of that amount 44 per cent has already been exploited at a recovery rate of 46 per cent. The hope is that EOR techniques will be able to prolong the profitable production of a number of fields on the NCS and unlock a further 2.5 billion Sm³ of oil (15.7 billion barrels) up to 2050 at a recovery rate above 60 per cent. In January 2013, NPD Director of Environment & Energy, Arne Holhjem, stated that EOR technologies had “a promising, but unproven technical and economic recovery potential on a reservoir and field level”. With this in mind, the Statfjord Late Life Project - in success and failure - will be the blueprint for a life extension and EOR policy to shape the future of an entire nation’s fortunes. Linda K. Høiland, Head of Petroleum Technology, Statfjord A Platform, Statoil will be delivering the keynote presentation at the Mature Fields Stavanger conference specifically on The Statfjord Late Life Programme. To book your place now contact us on 0800 652 2363 or +44 (0) 20 7368 9300 or email [email protected] now! .