As hard-to-abate sectors attempt to reduce CO2 emissions, the interest in efuels continues to rise. efuels, short for electrofuels, are a class of synthetically produced hydrocarbons which achieve lifecycle carbon savings compared to traditional reservoir-sourced hydrocarbon-based fuels. They approach carbon neutral following the consumption of CO2 in their production, which is then re-released into the atmosphere when combusted. Also known as power-to-liquid fuels, efuels have the same chemical structure as conventional fossil fuels so act as a drop-in replacement fuel, meaning they are interchangeable within current engines and fuel systems. The first Efuel World Summit took place in December 2022 and presented insights from across the value chain and political framework, which are both enabling and restricting the deployment of efuels.
why efuels?
Electrification of sectors such as heavy-duty transport, shipping and aviation is a challenge due to stringent energy density requirements as a result of space and weight restrictions. Efuels can provide the physical properties of traditional hydrocarbons without the emissions intensity, enabling low-carbon heavy-duty transportation.
Aviation in particular is driving efuel development with examples including the Airbus partnership with the SAF+ Consortium in Canada, the HyshiFT Consortium in South Africa and the Liquid Wind consortium in Scandinavia [3]. A controversial source of efuel investment has been the luxury car brand, Porsche. Porsche funded HIF Global’s Haru Oni demo plant in Chile, which produces efuels consumed in Porsche’s Experience Centres. Funding is generally positive for market uptake, but in this case it could result from a reluctance to EV’s. Cars are easily electrifiable and don’t require efuels to decarbonise and the consumption of efuels in cars deprives them from hard-to-abate which need them to decarbonise. Efuels must be prioritised in these sectors for society to experience the most climate benefits, an opinion also voiced by some Members of European Parliament at the summit [1]. Nonetheless, this case is fairly unique and may not present as much of a threat if governments follow the European Parliament’s vote to ban the sale of petrol and diesel cars by 2035 [4].
image sourced from Infinium
The source of CO2 can also present challenges. One pathway is through partnerships with industrial emitters to identify a high concentration CO2 stream to capture. Infinium’s partnership with ArcelorMittal to utilise captured CO2 from their steel plant in Dunkirk is a current example of this [1]. As sectors electrify, there may be fewer CO2 emission sources and efuel producers will have to implement technologies such as Direct Air Capture (DAC) and biomass which carry their own associated economic, operational and environmental challenges. DAC is an early-stage technology that requires scale-up, reduction of energy use, demonstrated industrial operation and cost reduction to commercialise. However, some advocate for DAC as key to an efuels ability to close the carbon cycle, whereas point-source CO2 capture will still contribute to atmospheric GHG accumulation [2].
There are also some uncertainties regarding the full extent of environmental benefits of efuels. In addition to the high energy consumption for the high temperature synthesis, producing green hydrogen is water intensive. This could present an obstacle to efuels being geographically independent in countries with scarce water. Furthermore, the combustion of efuels in internal combustion engines still produces NOx and particulates, leading to harmful effects on the environment and society. Efuels produced via FT lack aromatic molecules that prevent leaks in conventional aircraft fuel systems so need to be blended with kerosene for Sustainable Aviation Fuel (SAF) applications, further inhibiting its environmental credentials [2].
Market expansion will involve scaling of hydrogen electrolysis and DAC capacity which can be achieved through industry collaborations across the supply chain. The efuel business case is also enabled by government incentives, which need to be amplified for the sector to attract investment. The role of efuels in the broader context of the transition to a cleaner and more sustainable energy system must be further
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Presentations from the E-Fuel World Summit 2022 https://www.e-fuelworldsummit.com/
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Low-carbon fuels for aviation, A Fantuzzi, P A Saenz Cavazos, N Moustafa et al., Briefing Paper No 9 March 2023, Institute for Molecular Science and Engineering, Imperial College London, doi.org/10.25561/101834
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Sustainable Aviation Fuel – Ready for lift off? KPMG, Aviation 2030 https://assets.kpmg.com/content/dam/kpmg/uk/pdf/2022/11/sustainable-aviation-fuel.pdf
