Two cold waves swept across much of Spain in quick succession during January and February, driving temperatures downward and pushing natural gas consumption far beyond typical winter expectations. Enagás, the operator of the Spanish gas system, activated the gas network’s security measures as demand surged in homes and businesses due to the cold.
The sharp rise in use, coupled with reduced injections into storage tanks during the cold season, led gas operators to draw on stored reserves that had built up earlier in the winter. The government acknowledged an extraordinary state of security of supply, estimating that existing reserves could cover all residential and commercial gas needs for about 40 days even if imports were interrupted completely.
Three underground storage facilities in Spain currently hold more than 27,500 gigawatt hours (GWh), about 78% of their total capacity. Regasification plants, which receive gas from ships, maintain roughly 12,600 GWh in reserve with a filling level near 55%.
shielded gas consumption
Gas stored in underground tanks equates to about 29 days of national demand, while storage plants cover roughly 15 days. The energy sector applies adjustments in evaluating security of supply coverage, since reserves do not simply translate across all deposit types due to differing withdrawal rates. Accordingly, the minister of energy estimates that all storage and grid reserves together correspond to about 36 to 40 days of national demand.
The unexpectedly high demand during the cold season led Spain to use around 15% of its current gas reserves in a single month, pushing warehouse occupancy below 80% for the first time in seven months. This level had been exceeded again in August, as part of ongoing EU strategies to shield energy systems from potential supply disruption, including concerns over Russia.
pre-winter highs
Three underground storage tanks in Spain reached occupancy above 96.6% with a peak of around 34,000 GWh in November, a level that prompted Enagás to delay some gas deliveries. Storage facilities shed about a quarter of their reserves from pre-winter highs. By late January, the cold spell pushed occupancy down to 90%, and by late February the level fell below 80%.
Even with the drop in utilization, Spain remains among the EU leaders in storage occupancy, maintaining an average around 55% of continental storage capacity. Regasification plant tanks show about 55% capacity filled. In the last two weeks, occupancy rose from 46% after the most recent cold wave, but still trails the 80% peak reached in November.
Enagás declared an extraordinary operating state in response to the January 22 to February 4 cold wave. Gas records show demand deviated by more than 13% from forecasts under normal weather, with consumption 934 GWh above initial estimates. In the later emergency declared from February 26 to March 4, extraordinary demand rose by 1,695 GWh in a single week, a deviation close to 41% above earlier projections.
anti Putin shield
The European Union has pursued a strategy to reduce its heavy reliance on Russian gas and strengthen energy security for this winter and next. Brussels proposed creating a shield to guard member states against supply shocks, including an obligation to gradually fill gas tanks. The plan envisioned storage levels above 80% by November 1 of the current year and above 90% into 2026. Most member states have exceeded their targets. Despite higher winter demand, EU storage is around 59% full, while the continental average stood near 95% before any renewed fuel burn prompted by colder weather.
Spain began building an anti-Putin shield at the onset of the Ukraine conflict, out ahead of EU measures, and by late March last year—shortly after the war began—raised safety stock requirements for gas retailers from 20 to 27.5 days of firm consumption.