'Flex SAF’ Redesign at Starling

Carbon Neutral Fuels Unveils ‘FlexSAF’ Design to Boost Project Starling SAF Output by 70% to 42,000 Tonnes per annum

• Innovative FlexSAF architecture enables simultaneous eSAF and advanced bioSAF production on a single brownfield site in West Cumbria.

• Redesign increases total facility output from 25,000 to ~42,000 tonnes per annum (tpa) SAF output, reducing production costs per tonne.

• Process optimisation recycles naphtha and tail gas by-products to maximise high-value jet fuel output.

• Engineering is under way with io consulting ahead of full planning submission in Spring 2028 and targetfirst fuel in Q4 2031.

Carbon Neutral Fuels (CNF) has unveiled ‘FlexSAF’, a flexible plant design that enables the production of both eSAF and advanced bioSAF at a single facility.

Debuting at CNF’s flagship Project Starling site in Workington, West Cumbria, the FlexSAF design’s higher output contributes to solving the SAF supply gap, where industry professionals are concerned that statutory UK and EU SAF mandates are rising faster than dedicated production capacity can be built.

By integrating dual feedstock pathways (eSAF from biogenic CO2, water, renewable electricity, and advanced bioSAF from biomethane), FlexSAF gives Project Starling a more diverse feedstock base. Both pathways feed into a single, shared Fischer-Tropsch (FT) synthesis and upgrading line, increasing SAF target output to approximately 42,000 tonnes per year. This shared infrastructure is expected to significantly lower the production cost per tonne of fuel while offering flexibility within plant parameters to adjust the production mix in response to feedstock availability and market demand.

Process optimisation work has expanded target SAF production by 70%, taking Project Starling from 25,000 to approximately 42,000 tonnes of SAF annually. By recycling by-products (naphtha and tail gas) back into the syngas stream, virtually all output is converted directly into aviation-grade jet fuel. This commercial scale hybrid design is expected to be a UK-first.

Following the signing of a Planning Performance Agreement with Cumberland Council in June 2026, CNFwill host a public drop-in session for the local community on 15 October 2026. A full planning applicationwill follow in Spring 2028, targeting first fuel production in Q4 2031.