Summary
- Synthetic fuels can power traditional internal combustion engines (ICEs) with minimal changes to infrastructure, offering a lower-emission alternative.
- Automakers like Porsche are investing in synthetic fuels to preserve ICE vehicles as the world moves toward greener transportation.
- High production costs make synthetic fuels significantly more expensive than fossil fuels, limiting their mass-market viability.
- Synthetic fuels reduce CO₂ emissions by around 85%, but they are still not zero-emission and cannot match battery electric vehicles (BEVs) in efficiency.
- Due to energy demands and limited supply potential, synthetic fuels are likely to serve niche roles, complementing rather than replacing BEVs
Synthetic fuels also known as e-fuels, are generating a lot of buzz as a possible stepping stone towards decarbonization, providing a clean way to power internal combustion engines (ICEs) without the need for completely overhauling fueling infrastructure. Synthetic fuels offer several appealing benefits, including compatibility with conventional internal combustion engines and traditional service stations, as well as the use of renewable feedstocks like captured carbon and green hydrogen. Yet, despite the benefits, synthetic fuels are not the magic solution to making transportation carbon-neutral nor a replacement for battery electric vehicles (BEVs).
The process of producing these fuels remains costly and energy-intensive, leaving an efficiency cap on production. Moreover, although synthetic fuels do help lower emissions, they are not 100% carbon-neutral and don’t come close to the zero-tailpipe emissions that BEVs offer. But in the race for a sustainable transport future, synthetic fuels simply cannot compete with electric vehicles, so even if they offer some advantages, this is bad news, as this article explores.
The Familiar Fuel with a Future Twist
Carmakers like Porsche, BMW, and Toyota are embracing synthetic fuels as a sustainable solution for internal combustion engines (ICEs) in an increasingly electrified world. These fuels do not require ICE engines to be modified, allowing gasoline car owners to continue using their vehicles, as they are produced from carbon capture and the use of renewable hydrogen. Furthermore, with minor modifications (a simple pump change), we can use synthetic fuels in the current refueling infrastructure. In contrast, hydrogen requires storage at high pressures (approximately 700 atmospheres) and a completely different and more complex fueling infrastructure.
Among these car manufacturers, Porsche in particular has also been leading the charge, setting up a synthetic fuel production pilot plant in Chile (and other initiatives). The company promotes synthetic fuel as a means to maintain the thrill of ICEs without the fossil fuel carbon penalties. Toyota has also expressed interest, in backing synthetic fuels as a low-carbon complement to BEVs and providing consumer choice in cleaner technologies. Compatible with existing infrastructure and able to fuel existing vehicles, synthetic fuels offer the hope of a future where ICEs can exist alongside an ice-compliant planet (but can they scale?).
The Price Tag of Clean Combustion
Here, synthetic fuels hold an attractive green promise—but at a premium. The reliance on renewables makes carbon capture and electrolysis costly. However, despite projections from the eFuel Alliance suggesting that the costs could drop to between €1.38 and €2.24 per liter ($1.63 to $2.64) by 2050, other experts remain unconvinced. Bosch asserts that the price of synthetic fuel could drop to as low as €1.20 ($1.41) by 2030, but it is more likely to hover around €3-4 ($3.54 to $4.72) per liter, or more than $13 per U.S. gallon equivalent.
That’s a significant difference from the average U.S. price of gasoline, which is approximately $3.10/gallon as of now. These exceptionally high prices are the primary reason synthetic fuels won’t work for the vast majority of consumers, particularly with lower electric prices for BEVs. While this gap may close over time as technological advances and scaling production lower the cost of these fuels, synthetic fuels are likely to remain a specialty commodity for the foreseeable future, constraining their uptake.
From CO₂ and Hydrogen to Synthetic Fuel: A Complex Recipe
Synthetic fuels are created by combining captured CO₂ with hydrogen produced via renewable energy-driven electrolysis. This chemical process produces hydrocarbons similar to those in traditional fuels but offers a lower-emission alternative for internal combustion engines. According to Porsche’s VP Dr. Frank Walliser, synthetic fuels can reduce CO₂ emissions by around 85% compared to fossil fuels, offering a cleaner combustion profile that could help ICE vehicles contribute to emissions reduction goals. However, the current supply projections fall significantly short of what would be needed for widespread adoption.
For example, Porsche’s Chilean plant aims to produce just 55 million liters by 2024 and around half a billion liters by 2026. To put this into perspective, the U.S. alone consumed 467 billion liters of gasoline in 2020. Even with increased production, synthetic fuels would cover a fraction of global demand, meeting just 0.4% of projected EU road transport fuel needs by 2030. This shortfall underscores the challenge of relying on synthetic fuels to decarbonize large vehicle fleets on a global scale.
Efficiency in Question: Why Batteries Still Win the Race
While synthetic fuels may offer a low-carbon option for ICEs, they are far less efficient than battery electric vehicles. The production of synthetic fuels involves a multi-step process that consumes large amounts of electricity to capture CO₂, produce hydrogen, and synthesize these into fuel. This process results in an efficiency loss that is around four times greater than that of charging an electric battery.
In practical terms, this inefficiency means that powering a fleet of vehicles with synthetic fuel would require up to four times the electricity generation capacity needed for a comparable fleet of BEVs. By contrast, BEVs offer a direct, streamlined use of energy with minimal losses, maximizing the impact of renewable electricity. For countries aiming to reduce emissions and optimize energy usage, BEVs currently present a far more efficient and sustainable path forward than synthetic fuels, particularly on a large scale.
Looking Ahead
Synthetic fuels provide a potential pathway to lowering emissions from internal combustion engines by leveraging current infrastructure and fueling systems with minimal modifications. Going a step further, you could argue that with the support of automakers such as Porsche, they even contribute to keeping ICE vehicles roadworthy for longer in a sustainable way. Nevertheless, synthetic fuels have some drawbacks: high production and storage costs, limited scalability (certainly to displace petroleum), and efficiency three orders of magnitude lower than battery electric vehicles (BEVs). Synthetic fuels could find a place in niche markets, or complement electrification where BEVs fall short but likely won’t be a major future transportation solution. Instead, they underscore the importance of a balanced transition to cleaner mobility.
