Up until recently, a carbon-neutral combustion engine was the stuff of dreams. Now it may soon become reality. The secret lies in synthetic or carbon-neutral fuels, whose manufacturing process captures CO₂ — thereby making a significant contribution to limiting global warming.
How it works
For climate targets to be achieved, CO₂ emissions from traffic worldwide will have to be reduced 50 percent over the next four decades, and by at least 85 percent in the advanced economies.
After all, even if all cars were to drive electrically one day, aircraft, ships, and even trucks will still run mainly on fuel. Carbon-neutral combustion engines that run on synthetic fuels are thus a very promising path to explore — also for passenger cars.
2.8 gigatons of CO₂
could be saved by 2050 with the use of synthetic fuels.
Greenhouse gas becomes a raw material
Synthetic, or carbon-neutral, fuels capture CO₂ in the manufacturing process. In this way, this greenhouse gas becomes a raw material, from which gasoline, diesel, and substitute natural gas can be produced with the help of electricity from renewable sources. One further crucial advantage of the combustion engine using synthetic fuels is that the existing filling-station network can continue to be used.
The same applies to the existing combustion-engine expertise. Moreover, even though electric cars will become significantly less expensive in the years ahead, the development of these fuels may be worthwhile. Bosch has calculated that, up to a lifetime mileage of 160,000 kilometers, the total cost of ownership of a hybrid running on synthetic fuel could be less than that of a long-range electric car, depending on the type of renewable energy used.
Synthetic fuels - good to know:
Despite everything, considerable efforts are still needed before synthetic fuels can become established. The processing facilities are still expensive, and there are only a few test plants. The German Ministry for Economic Affairs and Energy is thus supporting synthetic fuels as part of its “Alternative energies in transportation” initiative. The widespread use of these fuels will also be helped by the increasing availability of, and thus falling prices for, electricity from renewables.
Synthetic fuels are made solely with the help of renewable energy. In a first stage, hydrogen is produced from water. Carbon is added to this to produce a liquid fuel. This carbon can be recycled from industrial processes or even captured from the air using filters. Combining CO₂ and H₂ then results in the synthetic fuel, which can be gasoline, diesel, gas, or even kerosene.
At the moment, producing synthetic fuels is a complex and expensive process. However, a production ramp-up and favorable electricity prices could mean that synthetic fuels become significantly cheaper. Present studies suggest that the fuel itself (excluding any excise duties) could cost between 1.00 and 1.40 euros a liter in the long run.
Synthetic fuels do not mean a choice between fuel tank and dinner plate, as biofuels do. And if renewable energy is used, synthetic fuels can be produced without the volume limitations that can be expected in the case of biofuels because of factors such as the amount of land available.
Synthetic fuels can make gasoline- and diesel-powered cars carbon-neutral, and thus make a significant contribution to limiting global warming.