French nuclear power reduction increases Spanish power exports, supports gas demand

Falling French nuclear power availability has increased demand for Spanish power, driving stronger gas-fired generation in Spain even as French pipeline gas continues to flow south across the border, according to an S&P Global Platts analysis Oct. 1.

The additional demand for power has added pressure to a Spanish gas system already tightened by sustained Combined Cycle Gas Turbine (CCGT) generation and declining LNG inventories, with stocks falling to particularly low levels toward the end of September.

LNG imports into Spain totaled 1.18 million mt over September, S&P Global Energy CERA data showed, compared to 1.21MMt imported in September 2025.

At the same time, Spanish LNG tanks were 52% full Sept. 30, according to Enagas. This was 12% lower year on year.

French pipeline exports to Spain averaged 2.8 million cu m/d over Sept. 1-30, compared with 1.7 million cu m/d in August, helping meet stronger Spanish gas demand as gas-fired plants increased generation to support power exports to France.

"Spanish LNG inventories fell sharply through September as LNG arrivals and Algerian pipeline imports declined, supporting PVB relative to PEG resulting in increased gas exports into Spain", according to Daniel Prichard, European gas analyst at S&P Global Energy CERA analytics.

"From what we've seen, Spain has been drawing down a lot of its LNG stocks, reaching 'record lows,' due to a supply curtailment at the Algeria-Spain Medgaz pipeline."

Platts, part of S&P Global Energy, assessed the October DES Mediterranean and DES Northwest Europe markers at $24.05/million British thermal units and $24.03/MMBtu, Sept. 30.

Meanwhile, the Spanish TVB month-ahead contract was assessed at $24.147/MMBtu, while Spanish PVB was assessed at $24.321/MMBtu, Sept. 30

Spanish PVB traded at an 89 euro cent/MWh premium to French PEG Sept. 30, after the premium widened to Eur1.15/MWh Sept. 29, its widest since October 2023. PVB last traded at a discount to PEG Sept. 8 before flipping to a premium the following day, Platts data showed.

The strength in Spanish gas demand had previously lifted the value of LNG held in the country's tanks, although that pressure has since eased as additional cargoes arrived. However, traders expect that France will continue to pull on Spanish power supply and Spain will need to supplement this with further gas and LNG imports.

The cross-border dynamic has effectively seen French gas move south into Spain before being used to generate power for export back north, highlighting the link between French nuclear availability and Spanish gas demand.

"In Spain, the current strength [in gas and LNG] above everything else is linked to the drought in France - right now power prices in Spain are below France and we are exporting a lot to France... The interconnector is large, so this changes the Spain-France balances," an LNG trader said. "Our CCGTs are running very high, so it will very much depend on France, and return of water to cool down nuclear."

"French are exporting gas to Spain, but if your tanks are empty, you need to pay whatever the price is to keep the plants running," another LNG trader said.

"As long as France doesn't recover nuclear output, the Spanish gas market will remain under pressure," the LNG trader said.

Nuclear production in France has averaged about 36 GW so far this month, a 10% decline compared to September 2025, system data showed.

This decrease was largely driven by low nuclear availability, with over 10 TWh of climate-related French nuclear power unavailable across 12 reactors.

Cross-border physical power flows from France into Spain have sat at over 400 GWh in September, much higher than the 150 GWh in September last year, Fraunhofer ISE data showed.

Power prices in Spain have more than doubled since September 2025, averaging at Eur143.26/MWh between Sept. 1-30, OMIE data showed.

"Spain has been running CCGTs 24/7 across summer. Spain says with solar, we only need minimal technical gas generation, but we've basically ran max capacity on both," a third trader said. "Not just LNG demand in Asia [to watch this winter] but watch nuclear output in France - this is relevant for Spain."