Record North Sea Decommissioning and Declining Output Test Pending Supply Boost Claims
Pending North Sea projects could add a quarter of UK annual gas output by 2030, but record decommissioning costs and declining production complicate the math.
UK North Sea decommissioning spending reached a record £2.6 billion ($3.5 billion) in 2025, the North Sea Transition Authority confirmed in a report on Thursday (2026-08-13), as the basin's operational wind-down gathered pace alongside falling production. Full-year output totalled 401 million barrels of oil equivalent, down 10 million boe from the previous year, with average daily production running at approximately 1.1 million boe per day.7,6
Efficiency gains cushioned the fall. NSTA operations director Tom Wheeler noted that a 1% improvement in production efficiency translated into an additional 21,000 boe per day, generating roughly 7.5 million extra barrels over the year. Production efficiency reached 76%. But plant failures remained the dominant drag, accounting for 83 million boe of losses, or 73% of the basin's total 114 million boe shortfall in 2025.6
Analysts have nonetheless been sizing what pending North Sea projects could deliver for UK gas supply. Wood Mackenzie, in analysis published by Montel on July 1st (2026-07-01), estimated a Labour administration could unlock approximately 330 billion cubic feet of gas from new discoveries by 2030, equivalent to roughly a quarter of the country's current annual production, if policy conditions were right.4
The most clearly defined new supply in the pipeline sits in Norwegian waters. Norway's energy ministry approved development plans on Tuesday (2026-05-19) for three southern North Sea gas fields, Albuskjell, Vest Ekofisk, and Tommeliten Gamma, after three decades of inactivity. ConocoPhillips, the operator, told Montel production should begin in the fourth quarter of 2028, at a daily rate of 5.7 million cubic metres, which it described as roughly 1.5% of average daily regional production. Combined reserves are expected to yield 90 to 120 million barrels of oil equivalent, mainly gas and condensate, equating to 150-211 TWh, backed by total investment of approximately EUR 1.8 billion.1
German analysts urged caution on the pricing implications. Speaking to Montel, they said the Norwegian restart would likely have "minimal impact" on gas prices under normal market conditions — but could "tip the scale" in an emergency supply crunch. They also flagged a risk of oversupply if Atlantic LNG imports into Europe increase at the same time as Norwegian volumes come onstream.2
Broader UK North Sea gas sentiment was already negative before those caveats were aired. An analyst told Montel in the week of August 3rd (2026-08-03) that the market mood was "bearish." BP's decision to sell its North Sea business was not the driver; the analyst attributed the pessimism to the basin's cost structure, calling North Sea gas "a high-cost product."5
ICE Endex TTF front-month gas was trading at €65.83/MWh on Friday (2026-08-21). For high-cost North Sea developments, that price sets the competitive reference, and any sustained softening in European gas would further pressure project economics where capital recovery depends on prices holding. [LIVE PRICES]
The decommissioning pipeline signals the pace of exit. CNR International, a Canadian oil firm, issued a tender in June (2026-06-01) for diving support vessels to dismantle the Toni and Thelma fields and associated central North Sea infrastructure, with work expected to begin in the first quarter of 2027, in a contract valued at up to £25 million.3
Wood Mackenzie's 330 billion cubic feet figure is conditional on policy support that has yet to be confirmed, and the Norwegian fields do not flow until late 2028. In the interim, plant failures will continue drawing down output from fields already in production. How far pending supply gains can outrun that decline rate, and at what TTF level those projects remain fundable, is the live calculation for operators holding undeveloped acreage across the basin.4,1,6