The key facts
- Peak gas demand — 493 million cubic metres/day (+2% year-on-year), reserve — 99 million cubic metres/day
- Electricity capacity margin — 5.9 GW (9.5% of peak demand), higher than the June estimate
- UK gas storage — 48% of capacity, the lowest in Europe according to Entsog
Sufficient supplies, but strained days ahead
The UK energy systems, according to forecasts by operators National Gas and National Energy System Operator (Neso), will be able to meet peak gas and electricity demand throughout winter 2026/27, but 'some tight days' are possible in December and January. Neso expects 'a small number of days with a low margin', when standard balancing tools will be required, such as electricity margin notices. The operator stressed that such notices signal the need for additional generation and do not indicate a risk of power supply disruptions.
Price rises amid the war
Since the start of the American-Iranian war in February 2026, month-ahead gas prices have risen by about 180% and electricity prices by 120%, which, according to The National, will increasingly be reflected in consumer bills.
Deal with the Belgian interconnector
On Thursday, National Gas agreed with the Belgian interconnector operator to expand gas import capacity, providing an additional 5% of forecast demand and greater network flexibility. The regulator Ofgem approved the agreement and will announce a consultation on recovering the costs of this capacity. Gas imports via interconnectors with Europe have declined in recent years due to the costs of maintaining them, including the two-way Belgian-British interconnector. At the same time, reduced gas stocks in Europe — also a consequence of the war — are likely to restrain imports, and disruptions on the global LNG market could further affect supplies.
Gas and electricity figures
Peak gas demand this winter is expected at 493 million cubic metres per day — 2% higher than last year, mainly due to greater demand from power stations; overall demand will fall by 1% due to consumers switching. Peak supply capacity is estimated at 592 million cubic metres per day, leaving a reserve of 99 million cubic metres; under a 'highly unlikely' stress scenario — the failure of the largest element of the transmission system — the reserve would fall to 18 million cubic metres. For electricity, the capacity margin will be 5.9 GW, or 9.5% of peak demand, in a typical cold period — a level comparable with recent winters and wider than during the 2022 energy crisis. Higher peak demand is offset by battery build-up, gas generation and wind energy; the margin is higher than the June estimate, as Neso now expects more wind generation during peak periods.
Low storage and operators' assurances
According to the European gas operators' network Entsog, storage levels in the UK are the lowest in Europe: 48% of capacity. Glenn Bryn-Jacobsen, National Gas's director of energy systems and resilience, said the analysis shows sufficient gas supply capability to cover demand throughout winter 2026/27 'even across a range of highly unlikely high-stress scenarios'.
