Are low-carbon combustion fuels for vintage engines the answer?
In the UK, classic cars hold a cherished place in the hearts of enthusiasts, with over 1.5 million registered vehicles supporting a thriving industry valued at £18.3 billion and employing over 100,000 people. However, as mainstream mobility trends towards decarbonization, classic car owners are increasingly seeking sustainable options. While electric conversions are gaining traction, concerns about authenticity and environmental impact persist. As an alternative, low carbon fuels are emerging, offering a potential solution.
Companies like Coryton Fuels are pioneering sustainable fuels, leveraging bio hydrocarbons from agricultural waste to create ethanol-free alternatives tailored for classic cars. Through a two-stage catalytic process, ethanol is broken down into constituent parts, resulting in hydrocarbons that mimic traditional fossil fuels without the associated emissions. This process, while carbon-intensive, ultimately recycles CO2 absorbed during feedstock growth, potentially making it carbon-negative.
Furthermore, the production process exhibits synergies with other industries, such as utilizing waste heat from bakeries and capturing CO2 emissions for reuse in different sectors. With careful development and adoption, these sustainable fuels could pave the way for classic cars to embrace sustainability without compromising their unique charm and heritage.
How does it work?
The production of sustainable fuels involves blending bio-derived hydrocarbons to create a petrol-like substance. However, key additives like octane boosters are typically sourced from fossil fuels, raising questions about the true sustainability of these blends. While bio-derived alternatives exist theoretically, they currently rely on fossil-derived chemicals in their production process.
To address this challenge, the industry employs a method called mass balancing, which allows for the co-processing of sustainable and fossil feedstocks in a known ratio. This enables a portion of the fuel to be certified as fossil-free, even if it contains fossil-derived components. While this approach has faced criticism for potentially enabling greenwashing, it offers practical benefits, such as repurposing fossil-derived components for non-fuel applications.
While mass balancing may be suitable for mass-market applications like sustainable aviation, it raises concerns in niche sectors like classic cars, where precise control over fuel composition is feasible. As the industry navigates these complexities, transparency and collaboration will be crucial in achieving meaningful progress towards sustainable fuels.
What else?
In addition to bio-derived hydrocarbons, sustainable fuels for classic cars incorporate various additives to enhance performance and prevent degradation. These include oxidation stability improvers, metal deactivators, and biocides to maintain fuel quality during storage. A detergency package is also included to prevent engine deposits.
Notably, these fuels omit tetraethyl lead, a once-common additive now recognized as harmful. Coryton, the fuel producer, opts against lead substitutes due to potential engine compatibility issues and environmental concerns. Instead, restoration companies often address valve seat wear during engine rebuilds.
While e-fuels, synthesized from atmospheric carbon and hydrogen, are explored, bio hydrocarbons currently offer scalability and availability advantages. Though fossil-derived content may be present in initial blends, Coryton aims for up to 80% renewable content in its upcoming fuel range.
Despite challenges and competition from alternative technologies like battery electric powertrains, sustainable fuels hold promise for preserving classic cars while reducing emissions. As the automotive industry navigates toward net-zero goals, these fuels offer a viable solution for heritage motoring enthusiasts.
Final word
We live in a world of progress, there is no simple answer. Sometimes a solution for one use becomes a solution for another.