Aviation fuel is made with air and solar energy

The prototype solar power plant is running from the roof of a university building. [Image: ETH Zurich / Alessandro Della Bella]

Air + Sol = aviation kerosene

Researchers at the Swiss Federal Institute of Technology (ETH) in Switzerland have developed a new technology that produces liquid hydrocarbon fuels exclusively from sunlight and air.

For the first time, they demonstrated the entire chain of thermochemical processes under real field conditions.

The solar plant produces synthetic liquid fuels that release as much CO2 during its combustion as the one previously extracted from the air for its production.

The chain combines three thermochemical conversion processes: First, the extraction of CO2 and water from the air; second, the thermochemical separation of CO2 and water; and thirdly, the subsequent liquefaction of the two compounds into hydrocarbons.

The solar radiation is concentrated in a parabolic mirror by a factor of 3,000, generating a temperature of 1,500 degrees Celsius inside the solar reactor. At the heart of the solar reactor is a ceramic structure made of cerium oxide, which allows a two-stage reaction - the so-called redox cycle - to divide water and CO2 into synthesis gas . This mixture of hydrogen and carbon monoxide can then be processed to produce liquid hydrocarbon fuels through methanol or Fischer-Tropsch synthesis.

"This plant proves that carbon-neutral hydrocarbon fuels can be made from sunlight and air in real field conditions.The thermochemical process uses the entire solar spectrum and occurs at high temperatures, allowing rapid reactions and high efficiency, "said Professor Aldo Steinfeld, the team's coordinator.

Solar Refinery

The mini-refinery solar, still in scale of prototype and under the prevailing climatic conditions in Zurich, produces about one deciliter of fuel per day.

The team is already working on a large-scale test of its reactor in a solar tower near Madrid, Spain. The next goal of the project is to scale the technology for industrial implementation and make it economically competitive.

"A solar plant that occupies an area of ​​one square kilometer could produce 20,000 liters of kerosene per day," said researcher Philipp Furler. "Theoretically, a plant the size of Switzerland - or one-third of the Mojave Desert in California - could cover the kerosene needs of the entire aviation industry. Our goal for the future is to produce sustainable fuels with our technology and to mitigate the global CO2 emissions. "

Source