Starting from air and sunlight, it is possible to produce alternative synthetic fuels to fossil fuels to power ships and airplanes: this is demonstrated by the first drops of methanol obtained thanks to a mini refinery built on the roof of the laboratory by researchers from the Federal Polytechnic of Zurich (Eth).
The experiment, published in Nature, could pave the way for zero-carbon hydrocarbon production, provided the technique is further optimized for large-scale use.
The goal is to use these synthetic fuels to power aviation and maritime transport, which together contribute 8% to carbon dioxide emissions related to human activity. The Swiss research group led by Aldo Steinfeld tried to produce them with a small pilot plant made up of three components: the first unit extracts water and carbon dioxide from the air; the second unit transforms the two ingredients into a mixture of carbon monoxide and hydrogen (the so-called 'syngas'); finally the third unit converts the syngas into liquid hydrocarbons or methanol. The experimental mini refinery also operates stably with intermittent solar radiation, producing 32 milliliters of methanol over seven hours during the day.
After demonstrating the technical feasibility of this production process, the researchers defined how to expand the system to meet the global demand for kerosene for aviation (which in 2019 amounted to 414 billion liters).
According to estimates, the production plants should occupy a total of 45,000 square kilometers (equal to 0.5% of the surface of the Sahara desert) and would require a significant initial investment that should be supported with targeted policies.