What are e-fuels?

Think the future is all about electric cars? Maybe not, because a new generation of man-made fuels could keep petrol and diesel cars on the road well beyond 2035...

fuel pump

Since the UK Government announced a ban on the sale of new petrol and diesel cars from 2030, it’s been clear that electric cars will be central to a more sustainable future. However, man-made e-fuels might also have a role to play.

The European Union recently agreed to exempt cars that run on e-fuel from its ban on new combustion-engined vehicles in 2035. This means these cars can still be sold in the EU after that date, provided they’re fitted with tech to prevent the use of fossil fuels in them.

So, what exactly are e-fuels? Are they a potential alternative to electric power, and are we likely to see them being used in the UK to power new or existing cars?

E-fuel production in Chile

What are e-fuels?

E-fuels – or electrofuels, to give them their full name – are a type of synthetic fuel suitable for use in combustion-engined vehicles. Unlike petrol and diesel, which are produced from oil, synthetic fuels are man-made from renewable resources.

E-fuels shouldn’t be confused with other synthetic fuels such as ethanol and biodiesel, though. Ethanol – which is made from plant materials – is used as a blending agent with petrol to increase octane and reduce carbon monoxide emissions, while biodiesel comes from vegetable oils and animal fats. E-fuels, on the other hand, are made by using electricity to combine hydrogen and carbon dioxide (CO2).

There are three steps in their production process. First, electricity (preferably from a renewable source such as wind, solar or hydro) is used to separate the hydrogen and oxygen atoms of water. Second, CO2 is captured from the air (or from industrial sources). Third, the hydrogen and CO2 are combined via chemical synthesis to create the e-fuels.


Are they clean?

In effect, e-fuels are carbon-neutral. This means the CO2 emitted while driving an e-fuel-powered car is offset by the fact that a similar amount is captured for the production process, so you’re not adding any additional CO2 to the atmosphere.

New BMW M240i Coupe engine

What are the pros?

  • E-fuels can power existing cars, vans and heavy goods vehicles (HGVs) without the need for modifications.
  • Refilling a vehicle takes only a matter of minutes, making it ideal for long-distance vehicles such as HGVs.
  • There’s no need to build new infrastructure; existing refineries, pipelines, fuel lorries and petrol stations can be used
  • E-fuels can be blended with fossil fuels to any ratio, in the same way that ethanol is blended into unleaded petrol (for example, ‘E10’ unleaded is made up of 10% ethanol).
Dramatic cuts in UK CO2 emissions

What are the cons?

  • E-fuels are currently very expensive to produce. A research and development executive at Porsche – a big investor in e-fuels – estimates that it costs £37.24 per imperial gallon at present, but he projects an eventual cost of £6.30.
  • E-fuels are not currently produced in large quantities.
  • Cars powered by e-fuels still emit harmful gases, thus contributing to pollution at a local level.
  • On a per-mile basis, it's argued that e-fuels require more energy – especially during the production process – than is needed to power electric cars
Audi Q4 Sportback e-tron charging socket

What does the UK Government say?

At present, the UK Government remains fully committed to the adoption of electric vehicles in the UK. When asked about the potential use of e-fuels here, a spokesperson told What Car?: “E-fuels are not proven technology, have expensive and complex supply chains, and emit much of the same pollutants as petrol and diesel. They might have a role for specialist vehicles, but we are not looking at them as a solution for normal cars and vans. We remain committed to helping people switch to electric vehicles, having invested £2 billion so far.”

The Secretary of State for Energy Security and Net Zero, Grant Shapps, cast further doubt over whether the UK will follow the same path as the EU, saying: “We are not in Europe; we don’t have to do what Europe does.” He also confirmed that the Government will hold firm on its ban on the sale of new petrol and diesel cars in 2030, along with the ban on hybrid cars in 2035.

However, the Government’s stance has been criticised in some quarters. A Transport Committee report by a group of cross-party MPs said the potential for synthetic fuels had been “overlooked” by the Government and an “exclusive focus on battery-electric vehicles risks failing to meet the UK’s climate goals”.

Porsche Taycan 2021 front

What does the car industry say?

Most car makers have already invested heavily in electrification, while ending development of new engines. Ford and Volvo, for example, have pledged to go fully electric by 2030, while Volkswagen intends for at least 80% of its global sales to be electric cars by that date.

On the other hand, some brands (such as Mazda and Porsche) have expressed interest in e-fuels. Porsche, for instance, has invested £62 million in Chilean firm Highly Innovative Fuels (HIF) – one of the world’s biggest producers of e-fuels.

While that’s pocket money compared with the £5.3bn Porsche invested in electrification last year, the brand clearly sees the potential benefits e-fuels, with research and development executive Michael Steiner saying: “The potential of e-fuels is huge. There are more than 1.3 billion vehicles with combustion engines worldwide. Many of these will be on the roads for decades to come, and e-fuels offer the owners of existing cars a nearly carbon-neutral alternative.”

In terms of output, HIF has an initial target of producing 130,000 litres of e-fuel annually, with this figure rising to 55 million litres by the middle of the decade. The firm also has plans to open two more facilities, one of which aims to produce 750 million litres annually.

However, while those figures show the potential for growth, the numbers are still tiny compared with the amount of fossil fuel consumed globally each year. The UK currently consumes 46 billion litres of fuel annually for road transport alone, according to the UK Petroleum Industry Association.

E10 biofuels fuel filling station labels

What Car? says...

E-fuels clearly offer potential as a viable sustainable alternative to electrification. However, there are currently big constraints in the form of price, scale and local-level pollution. As a result, we’re unlikely to see the widespread adoption of e-fuels any time soon (especially for new cars in the UK). But the EU exemption does leave the door open for the technology to be developed further, with it looking particularly suited to performance and classic vehicles.

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