What is e-Fuel
E-fuel is a synthetic fuel made by combining hydrogen produced from electricity with carbon-based feedstocks to create liquid hydrocarbons.
The “e” refers to electricity, because electrical energy is used to produce hydrogen before fuel synthesis begins.
In most cases, the hydrogen is produced from water molecules by electrolysis. There are emerging all-electric technologies that can crack green ammonia to provide low carbon-intensity (CI) hydrogen, as well.
e-Fuels are designed to function like conventional liquid fuels while reducing dependence on fossil carbon.
What makes a fuel an e-fuel?
A fuel is considered an e-fuel when electricity drives the hydrogen production step used in creating hydrocarbon molecules.
This typically means:
- Renewable electricity is supplied
- Water is split into hydrogen and oxygen in an electrolyzer
OR
ammonia is split into hydrogen and nitrogen in an electrified reactor - Hydrogen is combined with carbon
- Synthetic hydrocarbons are formed
The result is a fuel molecule that behaves like conventional hydrocarbon fuel.
How are e-fuels made?
Most e-fuels are produced through a power-to-liquids pathway.
The process includes:
Electrolysis
or electrified ammonia cracking
Electricity produces hydrogen from water
or from ammonia.
Carbon addition
Hydrogen is combined with carbon dioxide or carbon intermediates.
Fuel synthesis
Catalytic systems convert these inputs into hydrocarbons.
Product upgrading
The fuel is refined into target products.
See:
Are e-fuels the same as synthetic fuels?
e-Fuels are one type of synthetic fuel, but not all synthetic fuels are e-fuels.
Examples:
- gas-to-liquids fuels are synthetic fuels
- biomass-based synthetic fuels are synthetic fuels
- electricity-driven fuels are e-fuels (also a synthetic fuel)
The difference is whether electricity drives the hydrogen production stage.
What fuels can e-fuels become?
e-Fuels can be designed for multiple fuel markets depending on synthesis route.
Possible outputs include:
- sustainable aviation fuel
- synthetic diesel
- marine fuels
- chemical hydrocarbon intermediates
The hydrocarbon molecules are designed to fit existing infrastructure.
Why are e-fuels important for aviation?
Aviation is one of the sectors where e-fuels attract strong attention because aircraft require high-energy liquid fuels.
Battery systems are limited in long-haul aviation due to battery weight and energy-to-charge limitations.
e-Fuels offer a way to produce liquid fuel while using renewable electricity and carbon sources.
This makes them relevant to future sustainable aviation fuel strategies.
See:
Do e-fuels always use carbon dioxide?
Most e-fuel systems require a carbon source, often carbon dioxide.
Possible carbon sources include:
- captured carbon dioxide
- biogenic carbon dioxide
- carbon intermediates used in synthesis gas systems
The carbon source strongly affects overall fuel carbon intensity.
Are e-fuels available commercially?
e-Fuels are emerging commercially, but deployment remains early compared with established fuel pathways such as HEFA or Fischer-Tropsch synthetic fuel systems.
Growth depends on:
- renewable electricity cost
- hydrogen economics
- policy incentives
- carbon availability
How are e-fuels different from biofuels?
Biofuels begin with biological feedstocks, while e-fuels begin with electricity-driven hydrogen production.
Compared with biofuels:
- biofuels use plant- or waste-based carbon sources directly
- e-Fuels use hydrogen as the starting platform
Both can reduce fossil fuel dependence and mitigate scarcity of supply.
Frequently asked questions
Is e-fuel the same as power to liquids?
Power to liquids is the production pathway; e-fuel is the fuel category.
Are e-fuels renewable?
They can be renewable if powered by renewable electricity and low-CI carbon sources.
Can e-fuels power aircraft?
Yes. Synthetic aviation fuel is one of the main long-term targets.
Are e-fuels commercially available today?
Some early projects exist, but large-scale deployment is still developing.