If the CO2 content in the atmosphere continues to rise the way it currently does, researchers predict a global temperature increase between 1.4 ° C and 5.8 ° C for the 21st century. According to the scientists, this will lead to rising sea levels and an increase in environmental disasters. Wouldn’t it be great though if we could remove excess CO2 from the atmosphere? Wouldn’t it be even better if this CO2 could be used to produce environmentally friendly fuel? What sounds like a utopia is currently being realized by researchers at the Karlsruhe Institute of Technology.
Production of fuel with CO2 from the atmosphere
From a chemical point of view, fuels such as gasoline, are structured like chains in which carbon atoms are lined up like pearls. CO2, or carbon dioxide, is similar to a single pearl, as the small molecule has little more than a carbon atom in its structure. In a chemical reaction, many of these individual molecules can be threaded into a chain.
How is carbon dioxide turned into a chain?
In the so-called Energy Lab 2.0, at the Karlsruhe Institute of Technology, researchers have found out how fuel can be obtained from the CO2 in the air. To do this, they pump air into the plant, which has the size of a ship’s container, and filter out the greenhouse gas. The carbon dioxide is then combined with hydrogen and both are processed into hydrocarbon chains. This process is performed in several, energy consuming reaction steps.
It’s all in the mix
Gasoline, diesel, or kerosene, all these fuels can be obtained in the plant and used in combustion engines. The difference between these fuels is the mixture of differently sized hydrocarbon chains. The researchers can control the length of the chains they produce and thus which fuel they develop by adjusting the ratio of the starting materials and the reaction conditions.
How environmentally friendly is the method?
However great it sounds, this form of fuel production alone is not sufficient to solve the CO2 problem, as the greenhouse gas is initially taken from the atmosphere but is blown back into the air when it is burned in the engine. In a cycle, the CO2 is filtered out the air and fed back into it. After all, this can prevent the amount of carbon dioxide from increasing in the atmosphere, which is an improvement compared to continued use fossil sources for fuel production.
That said, it would be even better for the climate if the atmospheric CO2 could be used as a basis to produce substances that do not end up in the atmosphere when they are used. This is actually possible with the Energy Lab 2.0. The researchers are working on producing plastic and cosmetics as well as chemicals from CO2.
Yet, a lot of energy is required to run the plant; this energy must be produced in a green way, just like the hydrogen for the reaction, to make the method environmentally friendly. At this point, the whole process is still quite expensive and has yet to be established as a bulk good, for the fuel to be produced cheaper.
How does CO2 fuel compare to other renewable energies?
The CO2-based fuel has fewer disadvantages than other renewable energies or means of transport.
• Bioethanol, which is added to fuel in some countries such as Germany, is controversial, as food is often used for its production. This does not seem right to many people when others are starving at the same time.
• The production of batteries for e-cars is so energy-intensive that the cars only become environmentally friendly after they were driven with renewable electricity for about 100,000 kilometers. In addition, a lot of lithium is required for the manufacturing of the batteries, the mining of which usually takes place under environmentally harmful, inhumane conditions.
Together with green-produced hydrogen, CO2-based fuels are promising options for environmentally friendly transport and more. The German company Thyssen-Krupp is currently experimenting with hydrogen-powered blast furnaces to produce steel in a climate-friendly way.
Hydrogen and CO2-based substances are ideal for storing environmentally friendly energy, the production of which is known to be subject to fluctuations. Thus, photovoltaic panels produce most energy midday, while we need energy throughout the day. The solar power could be used to produce hydrogen or CO2-based fuels, like in a battery, the energy would be stored until it is used in a car or production plant. A single Energy Lab 2.0 system fits into a sea container. Several of them can easily be placed at a solar park. The CO2 would not disappear out of our atmosphere with this solution, but the increase and thus the consequences of the climate crisis could be reduced drastically.
„Doktor Whatson“ on Youtube: https://www.youtube.com/watch?v=qq0fjl0LQXo
3sat Makro, Sendung vom 25.08.2020
https://www.pv-magazine.de/2019/11/12/thyssen-krupp-testet-den-einsatz-von-wasserstoff-im-hochofen/ vom 12.11.2019 Autor RALPH DIERMANN, gesichtet 11.09.2020