E-fuel – everything you need to know about the synthetic hope for combustion engines

The European Parliament on Tuesday formally approved a law to effectively ban the sale of new petrol and diesel cars in the European Union from 2035, aiming to speed up the switch to electric vehicles and combat climate change.

The only exception to the rule is that combustion engines could continue to be registered after 2035 – if they use fuels that are carbon neutral. 

So what are they and how much sense it actually makes? 

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The broadest definition of a synthetic fuel (or e-fuel) is quite simple – that the liquid fuel that is not derived from natural occurring crude oil. This is not limited to automotive fuel though, the use of synthetic fuels is also possible, for example, in aircraft engines as an alternative to current kerosene. In February 2021, the Dutch airline KLM made the world’s first commercial passenger flight using synthetic jet fuel produced from a sustainable source. Synthetic fuels are also mistakenly labeled as biofuels that are made from biomass, but it is not the same. 

A study by Bosch has shown that synthetic fuels used as an alternative to electrification could save up to 2.8 gigatons of CO2 by 2050. 


Synthetic, or carbon-neutral, fuels capture CO₂ which is, in many cases, a byproduct in the manufacturing process (some companies are already using CO2 to make vodkadiamonds and activewear with more to come). The much-shamed greenhouse gas then becomes a “raw” material, from which dieselgasoline, and substitute natural gas can be produced with the help of electricity from renewable sources


The history of e-fuels, or synthetic fuels, can be traced back to the early 20th century, when researchers began exploring alternative sources of energy and fuel production methods. E-fuels have evolved over time, with various methods and technologies being developed and refined

The genesis of synthetic fuels can be attributed to the 1920s when German chemists Franz Fischer and Hans Tropsch devised the Fischer-Tropsch (F-T) process. This innovative method transformed a mixture of hydrogen and carbon monoxide (synthesis gas) into liquid hydrocarbons suitable for fuel applications. Initially, the F-T process was predominantly employed to generate synthetic fuels from coal or natural gas.

World war II

Amid World War II, Germany experienced acute oil scarcities and relied on synthetic fuels, synthesized from coal using the Fischer-Tropsch process, to satisfy its fuel requirements.

Post WWII and the oil crisis:

After the war, synthetic fuels lost prominence largely due to the abundance of cheap oil. However, interest in synthetic fuels was revived during the oil crisis of the 1970s, when countries sought alternatives to petroleum-based fuels.

The rise of renewables

With the growing awareness of climate change and the need for sustainable energy sources, researchers began focusing on producing e-fuels using renewable energy. In the 21st century, advances in electrolysis, carbon capture, and fuel synthesis technologies have enabled the production of e-fuels using green hydrogen and captured CO2.

Current state

Today, e-fuels are being developed and tested as potential alternatives to fossil fuels for transportation and other applications. While they are not yet commercially viable on a large scale due to high production costs and technical challenges, continued research and development aim to improve efficiency and reduce costs. E-fuels have the potential to play a significant role in reducing carbon emissions and achieving global climate goals, particularly for sectors where direct electrification is challenging, such as aviation and maritime transport.

How are synthetic (e-fuels) made?

They are produced through a process that typically involves the following steps:

  • Electrolysis: Electricity, ideally from renewable sources, is used to split water into hydrogen and oxygen. This process results in the production of “green” hydrogen.
  • Carbon dioxide capture: CO2 is captured from the atmosphere, industrial emissions, or biomass sources. The captured CO2 can be purified and concentrated for further use in the process.
  • Synthesis: The green hydrogen and captured CO2 are combined in a chemical reaction, often facilitated by a catalyst, to produce hydrocarbons or alcohols. Common e-fuels include methanol, ethanol, and synthetic diesel or gasoline. The Fischer-Tropsch process, for example, is a well-known method for synthesizing hydrocarbons from hydrogen and CO2.
  • Refining: The synthesized fuel may undergo additional refining steps, depending on the required specifications for its intended use. This can involve processes like dehydration, distillation, or desulfurization to meet fuel quality standards.

What needs to happen before synthetic fuels become viable and established?

Getting synthetic fuels commercially viable and widespread will take some time and a lot of support (read subsidies and pressure) from local governments. What should make it easier that the expected price of renewable energy should decline over time, the process should get more efficient, and the current infrastructure (fuel pumps) can be reused. All this should help establishing the synthetic fuels gradually in the wider system. 

Companies investing into synthetic fuels

Numerous companies operating in the synthetic fuel market are striving to secure or enhance their market share in the upcoming years by introducing new products or expanding their businesses.


Last December, the German car manufacturer Porsche opened a factory for the production of synthetic fuels in Chile. In the pilot phase, it should produce about 130,000 liters of synthetic fuels per year, and the plan is to expand the capacity to about 550 million liters per year, which is still a negligible amount on a global scale. In Germany alone, for example, passenger cars consume several tens of billions of liters of gasoline and diesel each year.

The Porsche plant built in the Punta Arenas area produces hydrogen using electricity obtained from wind farms and then combines it with carbon abstracted from atmospheric carbon dioxide. Carbon-neutral hydrocarbon fuel (in terms of “well-to-wheel” is said to be on the same level as an electric car) can be burned in engines without any modifications. By the middle of the decade, Porsche plans to increase annual production to more than 55 million liters, and in 2027 it should even be 550 million liters. Porsche does not state the price of the fuel produced in this way.

We recommend watching the awesome video below to see more. Credit: @seenthroughglass

Zero Petroleum

Another company heavily investing into synhetic fuels is London-based “ Zero Petroleum” in the UK. which is using a similar approach to Porsche’s. 

In 2021, Zero Petroleum set a Guinness World Record for powering a jet plane entirely with synthetic aviation fuel. The fuel used to power the engines was 100% fossil-free. It’s considered a “drop in” fuel which means it can be used as a substitute for fossil-derived jet fuels, without the need for engine modifications.


ExxonMobil uses “methanol to gasoline (MTG) process which selectively converts methanol to a single fungible liquid fuel and a small LPG stream“. The liquid product is supposed to be essentially  conventional gasoline with low sulphur and benzene.


Sasol produces catalysts based on Fischer-Tropsch (FT) and will deliver it to Ineratec. The new facilities will become the largest production plant for paraffinic synthetic fuels in the world. The plant’s output is estimated to reach up to 2,500 tons per year, starting as early as 2023. This is an example of the government support as the The German Government  provides funding of around 6 million euros within a funding program of the Federal Ministry for the Environment, Nature Conservation, Nuclear Safety and Consumer Protection 

Reliance Industries

Indian billionaire Mukesh Ambani’s Reliance Industries make no secret about their ambition to become the world’s top blue hydrogen maker. The operator of the world’s largest oil refining complex will re-purpose plant that currently converts petroleum coke into synthesis gas to produce blue hydrogen while they wait for the prices of green hydrogen to fall. 


Royal Dutch Shell , one of the world’s largest oil traders, said it plans to start producing low-carbon jet fuel at scale by 2025. 



Bosch sees a place for renewable synthetic fuels and hydrogen fuel cells alongside electrification and is investing heavily into synthetic fuels. 

Disadvantages of synthetic fuels

Some say that synthetic fuels are four times less energy efficient than batteries. So, powering combustion engine cars with synthetic fuel will require four times more electricity than EVs, which, arguably, makes no sense. Even if the electricity used is renewable, some experts are concerned synthetic fuels will place huge demand on the global energy grid. 

Some also say that synthetic fuels share the same chemical properties as conventional petrol and diesel, which will heavily depend on the process used to make it and is somewhat still TBC provided the development made in the past few years. 


It is somewhat essential to recognize that synthetic fuels do hold the potential to provide a smooth transition for internal combustion engine (ICE) vehicles as the world moves towards a fully electric future. Executed well, E-fuels offer a climate-neutral alternative to traditional fossil fuels, enabling existing ICE vehicles to continue operation while reducing carbon emissions while reusing the current infrastructure. This could be particularly advantageous in sectors where electrification is challenging, such as heavy-duty transport, aviation, and maritime industries. By allowing ICE vehicles to run on e-fuels, we facilitate a more gradual shift towards electric vehicles (EVs), giving the automotive industry time to further develop EV technologies and expand charging infrastructure. Thus, e-fuels could serve as a crucial bridge, ensuring a graceful landing for ICE vehicles on the path to an all-electric transportation ecosystem.

Martin Shaw
Martin Shaw

Martin is an automotive enthusiast with a deep passion for all things cars. He has spent the last decade immersing himself in the industry, reading up on the latest models, attending car shows, and tinkering with his own vehicles. Loves: family, all things cars (apart from selling them), pizza.

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