After Germany's gamble, the European Union finally validated the principle of the end of thermal engine cars in new cars from 2035. Following Berlin's refusal to vote on this text, Brussels has also paved the way for vehicles running on synthetic fuels, called e-fuels, or electrofuels. Enough to save a few more years the technology of the thermal engine, where Europe excels much more than China, which quickly went electric.
Are synthetic fuels a credible alternative to electric? Some environmental NGOs consider them still polluting because they do not suppress nitrogen oxide (NOx) emissions. "They can play a useful complementary role for the large number of existing cars and niche segments", such as the very high end, commented for his part Oliver Blume, during the presentation of the 2022 results of Porsche, at the beginning of March.
From a technical point of view, the principle consists in replacing gasoline and diesel with a new fuel obtained without petroleum so as not to have to change equipment, be it engines and current vehicles. In a March 2022 paper, the International Council on Clean Transportation (ICCT), an independent NGO that aims to provide unbiased research and technical and scientific analysis to environmental regulators, explains the mechanism for making e-fuel. They are produced chemically by combining carbon dioxide (CO2) and hydrogen from the electrolysis of water.
If we want to use green hydrogen, it is necessary to carry out the electrolysis thanks to renewable electricity which would come from solar energy or wind turbines. “To capture CO2, we can, for example, treat industrial fumes. That of the atmosphere too, but it is more complicated, because it is not concentrated, "explains Florence Delprat-Jannaud, director of the energy products results center at IFP new energies (IFPEN). "Producing green hydrogen by electrolysis of water is a known process," continues the expert. However, it has the disadvantage of requiring a lot of energy. »
The price criterion for synthetic fuels will determine the extent of their success. For now, they are still expensive. Roughly speaking, three times more expensive than a liter of conventional gasoline at the pump. They are not yet produced in large quantities and are the subject of experimentation by industrial groups such as the German manufacturer Porsche, the Volkswagen subsidiary which has opened a manufacturing center in southern Chile, in the strait of Magellan, or the tanker Aramco. Porsche is talking about a price of 2 euros excluding tax per liter in 2030.
According to a recent study by the Institute for Climate Research in Potsdam (Germany), “to achieve cost parity with fossil fuels would then require CO2 prices in the region of 1,000 euros per tonne. In the long term, production costs of less than one euro per liter of e-fuel can probably be achieved." Much more reasonable amounts. “Costs are high today because there is no industry. But wind energy was expensive 10 years ago and today it is competitive. We must develop the sector so that prices settle down, ”notes Florence Delprat-Jannaud.
Especially since it is not necessary to limit oneself to noting the price when refueling, explain the specialists. E-fuels have a great advantage, especially as long as the electric charging infrastructures are not sufficiently developed. They make it possible to work with existing equipment, whether engines, thermal vehicles or service stations.
They also remain a very interesting solution for air transport and maritime transport, which emit a lot of carbon dioxide. “There is no alternative solution like the hydrogen and battery-powered plane to decarbonize long-distance flights. Synthetic fuels therefore have real potential for long-haul flights in particular,” said Florence Delprat-Jannaud.
According to her, energy sources, battery, hydrogen, e-fuels or biofuels, can complement each other. “The challenge is decarbonization. It is better to respect a principle of technological neutrality and not to put solutions in competition in order to have a portfolio of solutions”, explains the specialist.
