Turning biomass wastes into a viable carbon-negative fuel
“The carbon will be sequestered for a hundred years or more.”
Fossil fuels still dominate our economy and power most of our cars, airplanes and heavy goods vehicles. If Europe is to fully make the transition towards greener transportation – and a greener economy overall – then cost-effective carbon-neutral alternatives need to be found. To this end, the EU-funded NET-Fuels project is investigating whether biofuels produced from low-value agricultural residues could hold the key. The initiative, led by Andrea Contin from the University of Bologna in Italy, is developing a novel method of treating agricultural waste at high temperatures without oxygen. This produces a charcoal-like biochar, an oil similar to biodiesel, and a mixture of hydrogen and carbon monoxide called syngas. “Plants and crops take carbon out from the atmosphere as they grow,” explains Contin. “The biochar produced in this process retains this carbon. This can then be used in the soil, where the carbon will be sequestered for a hundred years or more.” Contin says this will enable the NET-Fuels process to be carbon-negative. In the second phase of production, the volatile syngas is separated from hydrogen and combusted with pure oxygen. The resultant CO2 is then mixed with the hydrogen and converted into methane by bacteria. “A key aim of ours is to see if we can produce methane this way, from CO2 and hydrogen,” adds Contin. “This will be a challenge, as bacteria are sensitive even to small levels of contaminants. This has only been tested in labs up until now.” If successful, the NET-Fuels project could represent a significant step forward in the production of economically viable and carbon-negative biomethane. The hope is that the process will create a new revenue stream for agricultural businesses, sequester CO2 in soil efficiently while fertilising it, and produce biomethane in sufficient quantities. “We will certainly be looking at the economic potential of this process,” says Contin. “This is one piece of a much larger puzzle.” The project also plans to set up a certification system for carbon sequestration to create an attractive market for biochar production.
Keywords
biomethane, biogas, natural gas, sustainability, renewable fuels, green energy transition, REPowerEU, Research and Innovation, renewable technologies, biomethane technologies, solar energy