E-fuels and piston engines

    Diesel and petrol engines can run climate-neutral, too

    E-fuels are on the verge of a breakthrough. They can be used in all of the approximately 1.5 billion cars with ICEs that will still be on the road around the world in 2030 and can be distributed via the existing gas station network. E-fuels will thus become an integral part of climate-neutral mobility.

    E-fuels are on the verge of a breakthrough. They can be used in all of the approximately 1.5 billion cars with ICEs that will still be on the road around the world in 2030 and can be distributed via the existing gas station network. E-fuels will thus become an integral part of climate-neutral mobility.

    Developing a European hydrogen network

    Electrofuels (e-fuels) are produced from 100% renewable electricity, water (electrolysis), and CO₂. From this, standardized fuels can be produced using power-to-X technology. Renewable electricity and thus hydrogen are thus the basis of every e-fuel. A very ambitious further expansion of renewable energies – either domestically or as imports – is therefore absolutely necessary. Liquid fuels and consequently e-fuels have a high energy density, and are easy to store and transport. In addition, a distribution network already exists by way of which e-fuels can be made quickly available everywhere. Unlike electrical energy, there is no loss of power when transporting over long distances or storing it for longer periods of time. Furthermore, there is a high demand for chemical energy sources not only in transport but also in industry.

    The German Association of the Automotive Industry (VDA) considers relevant sustainable, regenerative fuels as advanced biofuels (according to the new Renewable Energy Directive, RED II), hydrogen, and e-fuels. For the direct use of renewable hydrogen in vehicles, a comprehensive expansion of the European hydrogen infrastructure is imperative. Due to their volumetric energy density, liquid hydrogen and e-fuels offer great opportunities for climate-neutral long-distance transport. E-fuels are climate-neutral because exactly the same amount of CO₂ is bound in the fuel during production as is later emitted during use in the vehicle. The advantage is  that climate protection is ensured in the existing fleet.

    Energy demand of e-fuels

    E-fuels are expensive, but they will become much cheaper: The National Platform for the Future of Mobility assumes production costs of one to two euros per liter by 2030. These production costs already include the efficiency losses inherent in production. The efficiency losses can be put into further perspective if the utilization of renewable energies is considered in a global context: Photovoltaic and wind power plants have a two to four times better capacity utilization at optimal locations than those located in Germany. Thus, globally, the same number of wind power and photovoltaic plants are needed per kilometer driven for battery electric vehicles (BEV) and vehicles powered by e-fuels.

    Sustainable, regenerative biofuels from residual and waste materials, which therefore do not compete with agricultural land, should also be promoted. Conventional biofuels are rightly limited to a maximum of seven percent in RED II, and a further expansion of palm oil production is thus definitely ruled out.

    Ideally, e-fuels are produced exclusively with renewable energies. Put simply, hydrogen from electrolysis powered by renewable electricity is combined with carbon dioxide, for example from industrial waste gases or the air, to form a hydrocarbon that is neutral in terms of greenhouse gases. The terms power-to-chemicals (PtC), power-to-liquid (PtL), or power-to-gas (PtG) have become generally accepted for these power-to-X processes. In contrast to conventional biofuels from cultivated biomass, e-fuels are not in competition with food (tank to plate discussion).

    Another key advantage is that synthetic fuels are technically no different from their conventional counterparts. They can even be used in vintage cars, distributed via the existing filling station network and mixed with fossil fuels in any ratio (so-called drop-in capability). But the production of synthetic fuels is still comparatively complex and costly due to the small quantities involved. With the ramp-up, however, economies of scale would ensure a massive increase in efficiency. Thus, e-fuels could become a permanent fixture in transport in the future and make an important contribution to climate protection.

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