From Stranded Assets to Active Production: Making Mature Fields Work Harder

The UK North Sea has historically been a cornerstone of the UK's energy security, providing a significant portion of the nation's oil and gas production. However, as many fields in the North Sea reach maturity, production has begun to decline, resulting in increased technical challenges, ageing infrastructure, and the high cost of maintaining and operating offshore facilities, means that wells with ongoing production potential are progressively being shut-in, as shown in Fig. 1. The proportion of shut-in wells is significantly above the North Sea Transition Authorities (NSTA) target of 10% of well stock and is trending upwards, as shown in Fig. 2. Without significant investment in intervention activities, these reserves are destined to be left unrecovered. It is estimated that £10 billion (Woodmac, 2024) in pre-tax value remains locked within existing assets in the UK North Sea, offering substantial opportunities for those able to implement effective intervention strategies. Operators across the North Sea face mounting financial and regulatory pressures, including windfall taxes and evolving compliance requirements, which are constraining new infrastructure investment. New wells can no longer be relied on to maintain basin production; well intervention activities must form part of the ongoing strategy for the North Sea. The value of well intervention is particularly pronounced in mature fields, where operators seek cost-effective ways to boost production from existing assets at a lower cost per barrel than through new development. According to the NSTA, well intervention could bring hydrocarbons back online at an operational cost as low as £12 per Barrel of Oil Equivalent (BOE), on the face of it a compelling alternative to more capital-intensive drilling campaigns.