Last-minute pressure from Germany and to a lesser extent from other countries, such as Poland and Italy, to prevent the European Union from banning the sale of new cars with internal combustion engines after 2035 has opened up a new scenario in the automotive industry. . While some companies have long defined a roadmap to stop producing vehicles with combustion engines, Germany and its allies have gotten away with it. Brussels has finally agreed to incorporate synthetic fuels or e-fuels into community regulations so that they can be used in vehicles with combustion engines as they are climate neutral because they only emit previously captured CO?.
The EU regulations, reluctantly accepted by the Twenty-seven -the Spanish vice president for the Ecological Transition, Teresa Ribera, is one of the most belligerent with the agreement-, will require that all new vehicles sold have zero CO? emissions to from 2035, and 55% less CO? emissions from 2030, compared to 2021 levels.
To comply with the standard, automotive companies will not be able to manufacture cars with internal combustion engines that run on diesel or gasoline as before, but must run on neutral fuels. In this sense, the European Union will allow the use of synthetic fuels or e-fuels but, on the other hand, leaves out biofuels -obtained from plant biomass- because they will always have a carbon footprint derived from agricultural practices.
Both synthetic fuels, also known as e-fuels, and biofuels are liquid fuels, such as gasoline or diesel. The difference is that while the latter are fossil fuels and come from non-renewable sources, artificial fuels are not obtained from oil, but through chemical processes and renewable raw materials.
The basis for obtaining synthetic fuels consists of mixing hydrogen with carbon dioxide, explains Xavier Giménez, professor of Environmental Chemistry at the University of Barcelona. “The mixture allows us to produce a liquid substance that is combustible, and that is the key: that said substance is not solid or gaseous, but that it is liquid. Because in this way, the fuel is very compact and allows us to have a car with a 50-60-liter tank to easily travel 1,000 kilometers or more”, adds Giménez.
The procedure begins with obtaining renewable hydrogen from electrolysis, a process that consists of breaking down water into hydrogen and oxygen using electricity from renewable sources. At the same time, CO? is captured and mixed with hydrogen at high temperatures to obtain liquid fuel, explains the UB professor.
Xavier Giménez admits that many different substances can be manufactured. That’s what refineries do. He cites butanol and biodiesel as examples. “But it turns out that if we produce biodiesel we can also obtain it from certain crops, such as soybeans and other types of cereals.” It is what is known as biofuels.
Biofuels are fuels that are obtained through renewable sources, such as plants and animals. As with e-fuels, when burned, biofuels release CO? with no net carbon emissions. However, the European Union has left biofuels out of the agreement, despite Italy’s reluctance, due to the carbon footprint generated by agricultural practices.
Biofuels are classified into four groups, depending on the origin of the raw material from which they come and the processes used to obtain them.
They come from agricultural crops, such as sugar cane, beets or molasses; cereals such as wheat, barley or corn; or oils such as palm or sunflower. Since its raw materials are also a source of food, an ethical debate on speculation about crops has sometimes been generated.
They are mainly produced from solid urban and agricultural waste, as well as from forest biomass. This type of biofuels generate greater savings in greenhouse gas emissions than first generation biofuels.
They are those that are produced from raw materials of aquatic culture, that is, algae and microalgae. To improve its performance and productive characteristics, the algae can be genetically modified. These biofuels are not yet commercialized.
They are those who seek to genetically modify microorganisms to improve the efficiency in CO? capture and storage. As with third-generation biofuels, they are not commercialized for the moment either, although there are pilot plants in Brazil and the United States.
This is practically the case, explains Giménez. “To get electrofuel we mix hydrogen with carbon dioxide in the refinery. Biofuels are obtained by chemically treating the oil that is extracted from certain cereals”.
Professor Giménez explains that both methods have a very similar cost from an economic point of view, although he specifies that there are many variants that must be taken into account. “For example, if you live in an area where there is a lot of land to cultivate, it turns out that biofuel may be very cheap because you save on transportation. But it is not easy because the arable surface on Earth is highly exploited”, the teacher qualifies.
An analysis carried out by the European Federation Transport
The chemist adds: “As long as the price of a barrel of oil remains around 60-65 euros, synthetic fuel is already viable. The price would be similar to what we now pay for a liter of gasoline, between 1.5 and 2 euros per liter. What makes e-fuel unfeasible is that the price of oil falls to 20-25 dollars per barrel”. However, Giménez considers that “within 30 years, when the electric car is fully developed and electricity comes from renewable sources, synthetic fuels will not be able to compete with other energies.”
