For some years now, experts have been intensively discussing the extent to which fossil fuels can be replaced by renewable synthetic fuels. Research has focused mainly on applications for which there are currently no battery-electric alternatives, i. e. primarily air and sea transport. This focus is necessary because e-fuels will remain an expensive and rare commodity for the foreseeable future. Furthermore, in the domain of road transport, electric vehicles are already significantly more energy-efficient than combustion cars, cost competitive, and widely available. Accordingly, while e-fuels can serve as a supplement to the direct use of renewable electricity, they are not an equivalent alternative. Even when e-fuel production in “sweet spot” regions with highly favourable production conditions is presumed, energy efficiency and sustainability will need to remain a top priority.
In this discussion paper, we summarize the current state of scientific knowledge regarding the potential offered by e-fuels. Compared to the German version of this paper that appeared in autumn 2023, we have added a new chapter on e-fuel policies in selected countries, and have generally expanded the paper’s international perspective. Our aim is to provide an evidence-based foundation for current policy debates. If policymakers wish to ramp up global e-fuel production, then associated decisions must be made over the near term based on an internationally concerted strategy that is informed by clear priorities. To this end, it is crucial to distinguish between viable options and mere wishful thinking – that is, to separate the substance from the hype.