Fact check: Ofgem and National Gas plan will prevent tight supplies this winter

Ofgem is Britain’s energy regulator. It assesses risks in the gas system and consults on arrangements that affect network capacity. National Gas operates the UK’s gas grid. It manages the system that receives gas from production fields, terminals, storage sites and European pipelines, then supplies it to users.

Their roles meet in the current pipeline plan. National Gas arranged a deal to keep an interconnector’s capacity from falling by 25 million cubic metres per day. Ofgem released a consultation on October 20 to help compensate National Gas for that deal. The aim is to preserve supply capacity during severe winter conditions.

This does not create new gas supplies. It keeps an existing route open at its current capacity. With the reduction prevented, potential supply during the article’s most severe modelled scenario rises from 403 to 428 mcm/d. Ofgem says this should cover the modelled cold-day demand of 408 mcm/d, although further government measures are still needed.

Ofgem modelled peak demand of 408 million cubic metres per day on an unusually cold day. This is a forecast for consumption, not a measure of how much gas Britain uses every day. The figure helps test whether the system could meet demand when temperatures are especially low.

The gas grid could potentially receive up to 505 mcm/d from its available sources, assuming suppliers have gas available. Those sources include UK and Norwegian North Sea production, LNG terminals, storage sites, and pipelines to Belgium and the Netherlands. The figure describes capacity rather than actual flows.

In the rarest scenario, two Welsh LNG terminals go offline during the cold snap and the European pipeline also loses capacity. Supply would then be 403 mcm/d, below demand by 5 mcm/d. Keeping that pipeline unchanged raises the scenario’s potential supply to 428 mcm/d, above both 408 mcm/d and 417 mcm/d.

Normal capacity is higher than normal peak demand, but gas systems also plan for serious faults during extreme weather. Ofgem tested a scenario combining an unusually cold day with the loss of Britain’s biggest single gas source. This precaution asks whether the grid can cope when demand is high and supply suddenly falls.

The model assumes two neighbouring LNG terminals in Wales go offline, removing 77 mcm/d. It also assumes a planned 25 mcm/d reduction in an interconnector’s capacity. Under those conditions, potential supply falls to 403 mcm/d, while demand reaches 408 mcm/d. That creates a calculated shortfall of 5 mcm/d.

The combination is described as very rare because both events must happen together. Ofgem’s plan is intended to prevent the pipeline reduction, lifting potential supply in the same terminal-failure scenario to 428 mcm/d. The warning therefore describes a stress test, not an expectation of routine shortages.

The affected pipeline is the INT interconnector, which links Britain with European gas networks. Its capacity was 73 million cubic metres per day in 2020 and had fallen to 61 mcm/d. A further 25 mcm/d reduction was planned for October, which would have reduced the amount of gas that could enter or leave through that route.

That reduction matters most in Ofgem’s stress test. Overall potential supply would fall from 505 to 480 mcm/d if the pipeline change went ahead. If the two Welsh LNG terminals then failed during an unusually cold period, available supply would fall further, to 403 mcm/d.

Ofgem released a consultation to help National Gas be compensated for a deal that keeps the pipeline’s capacity unchanged. The arrangement is intended to prevent the 25 mcm/d cut this winter. That leaves potential supply at 428 mcm/d in the terminal-failure scenario, above the modelled 408 mcm/d demand.

The change is simple: the pipeline keeps carrying its current capacity instead of losing 25 million cubic metres per day. Ofgem’s figures start with 505 mcm/d of possible supply across all sources. A pipeline reduction would lower that total to 480 mcm/d.

The stress scenario then removes 77 mcm/d because two neighbouring LNG terminals in Wales go offline. With the pipeline cut, 480 minus 77 equals 403 mcm/d. Without the cut, the full 505 mcm/d remains available before that fault, so 505 minus 77 equals 428 mcm/d.

The extra 25 mcm/d is therefore preserved capacity, not newly produced gas. It changes the outcome of the modelled emergency. Supply rises above the 408 mcm/d unusually cold-day demand estimate, and also exceeds the 417 mcm/d figure for a repeat of the Beast from the East. The arrangement is a medium-term fix.

A shortfall would mean modelled gas demand was higher than the amount the grid could supply. In the specific Ofgem scenario, demand reaches 408 million cubic metres per day while supply is 403 mcm/d. The gap is 5 mcm/d, but the article does not describe exactly how the system would respond.

Andrew Bowie said such a situation could mean homes were not warm, lights did not come on, or industry did not function. Those were political claims about what the warning meant. The article also reports that Kemi Badenoch said Britain might not handle a single peak winter day. Neither statement provides a confirmed operational outcome.

The article explicitly says Ofgem’s report does not explain the real-world impacts of this shortfall. It does say National Gas lays out more detail, but the supplied text ends before that detail appears. The current proposal is intended to prevent the gap by raising potential supply to 428 mcm/d.

Britain’s gas system can receive supplies from UK North Sea production, Norwegian North Sea production, LNG terminals, storage sites, and pipelines to Belgium and the Netherlands. Ofgem adds the possible capacity from these sources to estimate how much gas could flow into the grid. The article puts that combined figure at up to 505 mcm/d.

When demand rises, the system compares this potential supply with expected consumption. It also tests what happens if a major source fails at the same time. In Ofgem’s example, two Welsh LNG terminals go offline, removing 77 mcm/d. A planned pipeline reduction would also remove 25 mcm/d, leaving 403 mcm/d against demand of 408 mcm/d.

Keeping the pipeline unchanged leaves 428 mcm/d available after the LNG failure. That exceeds the unusually cold-day estimate and the 417 mcm/d Beast from the East figure. The article describes this as capacity, not guaranteed actual flows, because suppliers must have gas available.