E-fuels for passenger cars, i.e. fuels synthetically recreated with the help of electricity, are repeatedly discussed. However, it is still unlikely that they will save the combustion engine from dying out. What exactly are e-fuels and what are their advantages and disadvantages?
The internal combustion engine is on the verge of extinction in Europe. From 2035, new cars with petrol or diesel engines will no longer be allowed to be registered. The hope of survival with the help of e-fuels has recently fallen again. Environmentalists welcome this, but parts of industry and politics consider it a mistake. What are the arguments?
What are e-fuels?
The "E" in e-fuels stands for "electric" and refers to production. The main ingredient is electrical energy, which is used to chemically recreate classic petroleum fuels from carbon and water. Unlike the so-called biofuels, the carbon does not come from biomass, i.e. plant or animal remains, but usually from CO2, which is taken from the atmosphere. This is available everywhere. The situation is different with the required water and green electricity. Above all, both cannot be found everywhere - just think of large solar parks in the desert. In addition, some definitions also include hydrogen under the term e-fuels. In this case, no addition of carbon is necessary during production.
Who will be able to refuel with e-fuels in the future?
Because e-fuels are synthetically reproduced diesel and petrol or kerosene, they can be used in all internal combustion engines that currently use comparable mineral oil fuels. A conversion of the motors is usually not necessary. Transport and filling station infrastructure could simply continue to be used.
Do e-fuels burn without emissions?
no Therefore, according to the current status, they are just as much subject to the EU ban on combustion engines as diesel and super. In addition to the usual pollutants such as NOx, particulate matter and CO, burning also produces CO2. Of the latter, however, only as much as was used in production. In terms of balance, e-fuels are therefore climate-neutral.
What other advantages do e-fuels have?
E-fuels could replace mineral oil fuel in everyday life relatively smoothly. Hardly anything would have to be changed in today's cars and the existing filling station infrastructure in order to meet the German, European and global climate targets. The conversion of road traffic to e-mobility would not be necessary, at the same time existing vehicles could continue to be operated relatively cleanly for decades to come. In addition, the synthetic fuel is in principle suitable for storing excess wind or solar power in a form that can be stored and transported.
Where can you buy e-fuels?
Availability is one of the big problems with e-fuels. The synthetic fuels are not available in large quantities either in Germany or anywhere else. The production of electricity-based fuels is currently barely going beyond the level of demonstration and pilot plants, and even the fastest imaginable expansion of refinery capacities could probably not close this gap in the foreseeable future. Even optimistic forecasts do not anticipate a significant production volume before 2030. 2050 seems more likely to many experts. From a purely technical point of view, at least, the synthesis does not appear to pose any major obstacles, even if, for example, development time is still needed for CO2 separation from the air on an industrial scale. Once the complete production chain is in place, it would even be possible to produce natural gas in this way, which is also suitable for operating car engines, in addition to diesel and petrol variants.
What do e-fuels cost?
The production of e-fuels is currently very expensive, and the fuel at the filling station would be correspondingly expensive. With increasing demand and favorable development of the electricity price, the price for synthetic fuels before energy taxes could fall by 2030. Optimists are assuming between 1.20 and 1.40 euros before taxes, but more cautious experts are also expecting values below two euros. That's less than half of current prices, but still a lot. For comparison: the share of production costs in the price of a liter of petrol is around 50 cents. Many studies therefore assume that consumer prices for e-fuels are always well above the respective level of conventional fuels.
What other disadvantages do e-fuels have?
Market ramp-up and more demand could shrink availability and price issues. But the real sticking point is something else: e-fuel mobility has a poor level of efficiency, which is mainly due to the energy-intensive production. From 1 kilowatt hour of invested energy, just 0.5 to 0.6 kWh liquid energy remains after hydrogen electrolysis, CO2 production, synthesis gas, crude oil and finally petrol production. If the electricity had been loaded directly into the electric car, at least 0.8 kWh would have ended up in the battery despite charging losses.
Because the electric motor also uses energy more efficiently, the overall comparison is even clearer in the end. The e-mobile generates a range of around 6 kilometers from 1 kWh of electricity. An e-fuel combustion engine would only travel around 1.5 kilometers with the same amount of energy input. Where there is currently one wind turbine, there will have to be four in the future in order to generate the additional amount of electricity for e-fuels. Some experts even assume that designer fuel has an energy balance that is six to seven times worse. The problem cannot easily be solved by relocating production to sunny areas. Because there, too, green electricity would first have to be produced for personal use in the interest of climate protection - not for export to Europe.
Why are e-fuels currently back in the discussion?
Most recently, the electricity-based designer fuels were discussed again as part of the EU ban on combustion engines. Parts of the automotive industry, the mineral oil industry and politics spoke out in favor of considering e-fuels in the strategy under the keyword "technology openness", but had little success. At the very least, the EU Commission should still examine the extent to which fuel could play a role in road traffic in the future. However, experts consider this clause to be fairly non-binding.
Who would benefit from a strong e-fuels role on the road?
Anyone living on any form of internal combustion engines or liquid fuels would have obvious benefits. So mineral oil companies and petrol station operators as well as parts of the motor vehicle industry including suppliers and workshops. Ordinary drivers could also benefit, although it is quite unclear who exactly and in what form. Whether e-fuels are a realistic option for commuters or residents of remote areas, or whether they would rather secure the operation of their automobile darlings for wealthy classic car collectors and hobby racers depends on many factors. As a normal consumer, however, you should probably not get your hopes up too much for a cheap and climate-friendly alternative to buying and operating an e-car.
What does the future of e-fuels look like?
It is undisputed that e-fuels will play an important role in the decarbonization of society. According to the current status, it is rather unlikely that they will do this in a private car. There, the significantly higher overall efficiency speaks for the battery electric car. As long as electricity from renewable sources is scarce, e-fuels in cars will compete with other electricity consumers - not only in industry and households, but also in other modes of transport. Because the designer fuels are also interesting for ships, airplanes and possibly also trucks. And there may be no alternative, because battery e-mobility is often not possible or only possible with difficulty given the necessary ranges in these areas.
