A shift in framing but not yet in physics

Electro-sustainable aviation fuel (eSAF) is increasingly presented in Europe as more than a decarbonisation pathway for aviation. With the launch of the European eSAF Coalition, formed by Arcadia eFuels, INERATEC, Norsk e-Fuel, SkyNRG, and ZAFFRA, the narrative has expanded into something broader: energy security, industrial competitiveness, and defence readiness.

The Coalition calls on EU institutions, national governments, and NATO partners to treat eSAF as strategic infrastructure, not a niche climate solution. Its central argument is direct: “Fuel sovereignty is becoming a strategic necessity for Europe. The ability to produce critical fuels domestically is essential for maintaining connectivity, industrial competitiveness, and defense readiness in an increasingly uncertain world.”

This is an important shift in framing. However, it does not change the underlying physical reality of the system. eSAF remains fundamentally a hydrogen-based synthetic fuel pathway, and its scalability is still constrained by the same bottlenecks.

eSAF is structurally a hydrogen system

At its core, eSAF is produced through a Power-to-Liquid (PtL) process:

renewable electricity → electrolysis → green hydrogen → CO₂ conversion → synthetic kerosene

Hydrogen is not a secondary input in this chain. It is the central energy carrier that enables the conversion of electricity and carbon dioxide into liquid hydrocarbons suitable for aviation.

In practical terms, hydrogen performs three roles at once. It stores renewable electricity in chemical form, supplies the hydrogen atoms needed to build hydrocarbons, and enables the chemical reduction of carbon dioxide into fuel molecules.

This is why many engineers in the sector increasingly describe eSAF plants as hydrogen systems with a fuel output, rather than fuel plants with a hydrogen input.

As one senior process engineer involved in European PtL development put it: “We are not building fuel plants. We are building hydrogen systems that end in jet fuel.”

The real constraint is not fuel synthesis

Technically, the synthesis of synthetic kerosene via Fischer–Tropsch or related pathways is well understood. The challenge lies elsewhere.

The key constraint is the production of green hydrogen at scale.

Electrolysis is energy-intensive and depends entirely on the availability of low-cost renewable electricity. On top of that, hydrogen requires compression, storage, and transport infrastructure, all of which add cost and complexity. These upstream requirements determine whether eSAF facilities can operate at scale or remain limited to demonstration and early industrial volumes.

A senior hydrogen industry executive summarised this constraint clearly: “We do not have a hydrogen technology problem. We have a renewable electricity and infrastructure problem.”

A sector dominated by announcements, not assets

Europe accounts for more than 60% of announced global eSAF production capacity. However, most of this capacity remains at early development stages, with many projects still pre-final investment decision.

The European eSAF Coalition reflects both the ambition and the constraint. It represents a multi-billion-euro pipeline of projects across France, Germany, the Nordics, Spain, and other aviation hubs, but also a sector struggling to convert announcements into financed construction.

To address this, the Coalition has identified four priority actions: treating eSAF production as strategic infrastructure, creating bankable demand signals, bridging the cost gap with fossil jet fuel, and opening access to Europe’s jet fuel market infrastructure to enable new entrants.

These priorities are not primarily about fuel chemistry. They are about investment conditions for hydrogen-based industrial systems.

A senior sector participant described the situation succinctly: “The molecules are not the problem. The problem is whether hydrogen demand can become bankable at industrial scale.”

INERATEC and the first step toward industrial reality

Within the Coalition, INERATEC represents one of the clearest examples of early industrial deployment. The company is developing modular Power-to-Liquid systems that convert green hydrogen and captured carbon dioxide into synthetic fuels, with operational and near-operational facilities in Germany.

This places INERATEC among the few European actors moving from demonstration-scale production into early industrialisation.

However, even in this case, scaling remains dependent on hydrogen availability. Without sufficient renewable electricity and electrolyser capacity, production growth is structurally limited.

In simple terms, the bottleneck does not sit in fuel synthesis. It sits upstream in hydrogen production.

Other Coalition members reflect the same structural reality

Norsk e-Fuel is developing large-scale synthetic fuel projects across the Nordic region, where abundant renewable electricity offers a potential advantage. Arcadia eFuels is advancing flagship developments such as its Danish project, aiming to establish commercial-scale PtL production. SkyNRG combines established sustainable aviation fuel operations with emerging eSAF initiatives such as SkyKraft in Sweden.

ZAFFRA, a joint venture between Topsoe and Sasol, focuses on industrial integration and project delivery from development through to operations, bringing refinery-scale execution capability into the sector.

Across all of these players, the same constraint appears: hydrogen production capacity and renewable electricity availability ultimately define scale.

Policy is moving faster than physical infrastructure

The European regulatory framework, particularly ReFuelEU Aviation, is creating binding demand for sustainable aviation fuels, including eSAF. This provides long-term certainty on consumption volumes.

However, upstream hydrogen infrastructure is not yet aligned with this trajectory. Electrolyser deployment, renewable generation build-out, and grid integration remain uneven and capital constrained.

This creates a structural mismatch: demand is increasingly mandated, while supply is still exposed to market risk and infrastructure bottlenecks.

A European Commission official working on fuel regulation summarised the issue clearly: “We can mandate demand for eSAF, but we cannot mandate the hydrogen infrastructure required to produce it.”

The rise of energy sovereignty as the dominant narrative

A noticeable change in the sector is the way eSAF is now being framed. The Coalition explicitly links synthetic fuels to energy sovereignty, supply chain resilience, and geopolitical stability.

This reflects a broader shift in European energy policy thinking. eSAF is no longer only about reducing aviation emissions. It is also about reducing dependence on imported fossil jet fuel and strengthening domestic fuel production capability.

In this framing, hydrogen becomes the enabling infrastructure for strategic fuel independence, not just a decarbonisation tool.

This shift matters because it influences how projects are justified, how funding is prioritised, and how governments assess infrastructure needs.

Hydrogen competition across the wider economy

Hydrogen is not a dedicated resource for aviation. It is a shared input across multiple sectors, including steel production, ammonia, chemicals, shipping fuels, and power systems.

eSAF sits at the more complex end of hydrogen use cases. It requires hydrogen not as a final product, but as an intermediate step in a multi-stage transformation process that ultimately produces liquid hydrocarbons.

This creates an allocation question at the centre of Europe’s hydrogen strategy: how should limited renewable hydrogen be distributed across competing sectors?

The answer to that question will strongly influence whether eSAF becomes a meaningful industrial pathway or remains a constrained niche.

Conclusion: eSAF depends on hydrogen more than aviation

The launch of the European eSAF Coalition marks an important moment in the sector’s development. It signals greater industrial coordination, stronger policy engagement, and a clearer framing of synthetic fuels as part of Europe’s energy security architecture.

However, the underlying system has not changed. eSAF remains a hydrogen-mediated fuel pathway, and its scalability depends primarily on the pace at which Europe can build out green hydrogen production and expand renewable electricity supply.

As one industry participant summarised: “If hydrogen scales, eSAF scales. If hydrogen stalls, eSAF remains a demonstration technology.”

The future of aviation fuels in Europe will therefore be determined less by fuel synthesis innovation than by the speed and scale of the hydrogen economy that underpins it.