Carbon-Neutral Liquid Fuels From Sunlight and Air

What is carbon-neutral, you may ask?

Also called carbon neutrality, CO2 neutral is a principle that’s based on the fact that carbon emissions, regardless of their place or source of origin, has the same impact on the world’s climate. Similarly, any greenhouse gases (GHGs) emission cuts, no matter where or how they occur, would benefit the global climate system at large.

Many states, corporations, organizations, and even individuals are actively working to offset their carbon emissions, hoping to achieve true carbon neutrality or zero carbon footprint, eventually.

One of the promising ways to remove as much carbon dioxide as possible from the atmosphere are synthetic hydrocarbons known as carbon–neutral fuels.

The Solar Refinery: Sustainable Carbon-Neutral Fuels

Conventional oil refineries transform crude oil into a variety of useful products that enter into many industries, such as gasoline, diesel, and other fossil fuels.

Researchers at ETH Zurich University in Switzerland thought about a revolutionary concept for a solar mini-refinery that works exclusively on sunlight and air to produce carbon-neutral fuels.

Now installed on the roof of Machine Laboratory building at ETH Zurich, this solar plant looks like a parabola that extracts water and carbon dioxide directly from ambient air. Using solar power, the system splits water and CO2 into syngas, a mixture of hydrogen and carbon monoxide, that can be then processed into synthetic liquid hydrocarbon fuels like kerosene.

Aldo Steinfeld is a Professor of Renewable Energy Carriers at ETH Zurich, and he led the present research.

“This plant proves that carbon-neutral hydrocarbon fuels can be made from sunlight and air under real field conditions. The thermochemical process utilizes the entire solar spectrum and proceeds at high temperatures, enabling fast reactions and high efficiency,” said Prof Steinfeld.

This is a significant step toward making carbon-neutral fuels a commercial reality, and help polluting industries, like aviation and maritime transport, offset their emissions and work on a more sustainable basis.

ETH researchers have done the legwork. Other researchers and engineers can take this solar plant concept and spin it into different iterations. They could make a sizeable parabolic structure, or a network of mini-solar refineries, whatever suits the needs, to produce solar fuels and cut carbon emissions.

Professor Steinfeld and his team are planning the construction of a large-scale replica of their solar plant in a solar tower near Madrid, Spain.

This technology comes as part of the larger Sun-To-Liquid EU project. Already, there are two official spin-offs of Steinfeld group’s mini-refinery. The first is Synhelion, which commercializes the technology for CO2-neutral drop-in fuels, and the other is Climeworks, a Swiss company, which markets its carbon capture technology.