718 Cayman GT4 RS

Make
Porsche
Segment
Coupe

It goes by many names - e-fuel, synfuel, synthetic fuel - and has featured in various news stories from Formula 1 in 2026 to Porsche keeping combustion alive. Most recently, the European Union's legislation for the 2035 ban on combustion was reworded to allow for the combustion engine to live on, with synthetic fuel posed as a potential enabler of this. Porsche, Bentley, Hyundai, and even Aston Martin have all been heavily pro the development of synthetic fuels, with the former running a 718 Cayman GT4 RS on the stuff as a demonstration of its capabilities, and other manufacturers are likely to get on board soon too.

But what is synthetic fuel/e-fuel? Why is it important? And crucially, why should you give a damn?

The TL;DR version is that synthetic fuel is carbon neutral gasoline that could keep gas pumping for decades to come and prevent the extinction of the combustion engine. The full explanation is a little more detailed than that.

What Is Synthetic Fuel?

Modern synthetic fuel is essentially the same as fossil fuel (gasoline, diesel, etc) in that it gets burnt by a combustion engine in exactly the same way. But the big differentiator is in how it's made. Instead of refining oil to create gasoline, eFuel - Porsche's name for synthetic fuel - is created by harnessing carbon dioxide (CO2) from the atmosphere, for example, from production plants, and hydrogen, earth's most abundant element, by means of electrolysis. These are then added together to create hydrocarbons - which is the same basic chemical structure of regular gasoline and diesel.

By using CO2 from the atmosphere that has already been emitted as pollution, the damage has already been done. Crucially, when burnt, the carbon emissions of synfuel do not add anything to the atmosphere that wasn't already there to begin with. This makes synthetic fuel carbon neutral in the combustion process, only emitting the CO2 that was used to create it in the first place; CO2 that was already polluting the atmosphere.

The caveat to this is that while the combustion process is effectively carbon neutral, the refinement of e-fuels isn't necessarily so. Harnessing CO2 and hydrogen from the atmosphere is energy-intensive - which has always been one of the big hindrances to the widespread adoption of hydrogen fuel-cell vehicles. That means that the creation of synthetic fuel is only carbon neutral if renewable energy sources - solar, wind, hydro-electric power, for example - are used in its refinement.

What Are The Benefits Of Synthetic Fuel?

The pros of using synthetic fuels should immediately be apparent to those of us with gasoline in our veins, the biggest of which is that our high-revving combustion engines can live on and that electric vehicles don't have to become the only means of buying a new car. Because the burning of e-fuels yields no additional carbon emissions, there is no need to ban combustion or rid the world of the combustion engine.

Because of this, we wouldn't have to trash the combustion engine, the efficiency and performance of which we have been honing for more than a century.

And, because synthetic fuels take the same form as regular gasoline and diesel, they could be distributed through regular gas stations - no need for new infrastructure and EV charging stations, or changes to our regular refueling routines. In global economies where infrastructure is already strained, retaining the network of gas stations we already have would prove invaluable.

Up to a lifetime mileage of 160,000 kilometers, the total cost of ownership of a hybrid running on synthetic fuel could be less than that of a long-range electric car, depending on the type of renewable energy used.

-Bosch

It really is that simple, as there are no changes needed to an engine or its fueling system to accommodate e-fuel. So long as the fuel is created in an environmentally sustainable manner - which is becoming more and more viable as many manufacturing plants across all industries are finding ways of powering operations in a carbon-neutral fashion - synthetic fuels are guilt-free.

There are other benefits. Bosch - a long-time supplier of automotive componentry and one of the companies involved heavily in developing synthetic fuels - has calculated that running a hybrid car like the Toyota Corolla Hybrid on synthetic fuel would have a lower total cost of ownership up to a mileage of 100,000 miles than a comparable EV, despite the fact that EVs are becoming more affordable to buy.

What Are The Cons Of Synthetic Fuel?

With every good, there's a bad. While synthetic fuels are not exactly a new concept - their history dates back to before World War II - the technology and developments required to produce them in an efficient manner are still in their relative infancy. At this point in time, volume, cost, and cleanliness (due to renewable energy during its refinement being essential to its carbon neutrality) remain the three biggest concerns.

How Much E-Fuel Do We Need?

According to the United States Energy Information Administration (EIA), about 135 billion gallons of gasoline were used in 2021 in the USA alone. That's not taking into account gasoline and other fossil fuels used to power trucking, shipping, and industry. How much synthetic fuel are we currently capable of producing?

Well, Porsche, which has been one of the biggest advocates for its development, is building a synthetic fuel plant in Chile with Siemens, Enel, and AME. Predictions from these companies suggest this one plant will be capable of producing 14.5 million gallons of synthetic fuel by 2024 - approximately the same amount used by the state of Texas in 2021 - ramping up to 145 million gallons by 2026. That's 1,000 times less than the US requirement alone.

Yes, other plants and other producers will also come online to boost production, with Bosch, Aramco, and many others joining in, but we're facing an uphill battle to produce enough synthetic fuel to power our cars, let alone our aircraft, ships, and industrial machinery.

In the meantime, supporters of e-fuels such as the eFuel Alliance are proposing an increasing admixture over the next three decades, starting with 4% supplementation of regular gasoline in 2025 and working up steadily to 42% by 2035, 80% by 2040, and 100% by 2050. The eFuel Alliance suggests this would also be an ideal way to mitigate cost increases, as the more we're able to produce e-fuels, the cheaper they will become.

How Much Does Synthetic Fuel Cost?

If produced on an industrial scale, prices of less than $2 per liter ($7.57 per gallon) could be possible.

-Oliver Blume, Porsche CEO

The rising cost of gasoline has been frightening since the start of 2022. At the time of publishing, a gallon of gasoline averages $4.605 in the USA according to the AAA, up by more than a dollar compared to a year ago. But at present, e-fuels are estimated to cost approximately $38 a gallon. All new technology is expensive. The same was true of EVs, and without government and state incentives, EVs would still be pretty pricey today.

But there's hope yet. Porsche CEO Oliver Blume recently went on record saying that the price of e-fuel could come down drastically. "If produced on an industrial scale, prices of less than $2 per liter ($7.57 per gallon) could be possible," said Blume, speaking of the 2026 production goal of 145 million gallons. That's still expensive, but others are more hopeful still. The eFuel Alliance believes costs could come down to at most $5 per gallon by the time we use 100% e-fuel in 2050, using the sliding admixture scale mentioned above.

Are E-Fuels The Answer?

BEVs aren't the right answer for the whole world right now. They are for certain parts of the world but not everywhere.

- Gill Pratt, CEO Toyota Research Institute

The truth is, there is no silver bullet when it comes to climate change. There is no one-size-fits-all answer that can reduce our impact on the environment. Casting aside our rose-tinted glasses, combustion really isn't that efficient. Using a combustion engine as a generator for electric motors is a vastly more effective way of using contained dinosaur-juice explosions, for example, and using solar power to recharge a battery is even more efficient still.

But EVs are not the only solution either. Gill Pratt, CEO of the Toyota Research Institute recently went on record with Autocar speaking of the consequences of the construction of EVs. "They're made using rare, mined materials - in contrast, an engine is made using more common materials - and weigh a lot," said Pratt, before suggesting that diversity could be good and that we don't need to jump on the hype train of a solely EV future.

So no, e-fuels are not the answer, or rather not the only answer, but that doesn't make them any less important.

The CarBuzz Take: E-Fuels Are Just As Important As Electrification

Personally, as much as I love combustion and want to see it last as long as possible, I also love seeing technological advancement. I also have a rational enough mindset to understand that for most of the population, a vehicle is a personal mobility appliance. For those people, there is no reason why a car shouldn't be electric - especially once range and charging capabilities remove the inconvenience factor.

But I'm a gearhead. Gasoline flows through my veins, my weekends are spent tinkering and autocrossing my two Mazda Miatas, and the sound of a high-revving V10 at full song evokes a response in my nether regions that my ex-girlfriends wish they could. And I'm not alone in wanting to see the combustion engine live on. Because driving for me, and many others, isn't about getting from A to B. Driving is an experience, and the combustion engine, the noise it makes, the way it builds and delivers its power, and the delicate balance of throttle application to get the most out of a million micro-explosions are experiences I simply can't imagine my life without.

For me, and those like me, synthetic fuels are a godsend.

No, they aren't the only answer. Nor do they need to be.

Since when did we settle for this idea that everyone needs to use the same technology? The old adage of variety is the spice of life rings true here, and bashing the personal choices of a group of individuals when it comes to what they drive is childish. We don't mock someone for driving a convertible instead of a practical station wagon. We don't all wear the same beige clothing because it's cheaper to manufacture and less offensive on the eye. We don't all eat the same food. So why should we begrudge someone for choosing an EV, or a hybrid, or a hydrogen vehicle that suits their lifestyle?

Synthetic fuels unlock yet another avenue, giving us choice. How would you like to be green? EV? Hydrogen fuel cell? Hydrogen combustion? Synthetic fuel? As long as no one is getting hurt and the environment isn't being damaged, who cares which you choose? Choose the solution that best fits your needs, and let others do the same.