One important measure to mitigate climate change is to emit less greenhouse gas. The transport sector in particular can make a significant contribution here, for example by replacing gasoline derived from fossil petroleum with bioethanol made from renewable raw materials, like Miscanthus.
A significant reduction in greenhouse gas is feasible. This is the conclusion reached by researchers at the University of Hohenheim in Stuttgart. The trick: A combination of bioethanol production from renewable resources with carbon capture and storage technologies. Depending on the calculation approach used, a reduction of more than 100 percent compared to the EU benchmark for fossil fuels is thus likely—meaning there can even be a negative CO2 balance. The processes uses the giant grass miscanthus, which has successfully proven its suitability for this form of biofuel production within the European EU joint project GRACE.
How this already established technology can be further optimized is currently being investigated by researchers within the joint project “Growing Advanced industrial Crops on Marginal Lands for Biorefineries” (GRACE) in a new approach: “If you combine the production of bioethanol with carbon capture and storage technologies, you could help remove carbon dioxide (CO2) from the atmosphere,” stated project coordinator Dr. Andreas Kiesel from the Department of Biobased Products in the Bioeconomy at the University of Hohenheim.
According to Dr. Jan Lask, who is in charge of this subproject at the University of Hohenheim, the location offers two major advantages: “For one thing, the refinery is in close proximity to depleted oil reservoirs that can be used for CO2 storage and these reservoirs are, according to experts, stable over the long term for the next 1,000 years and beyond.”
Miscanthus—more than just an alternative to fossil raw materials
The researchers are paying special attention to Miscanthus x giganteus. “Miscanthus can be cultivated on so-called marginal land that is not suitable for profitable cultivation of other crops. In this way, unused land can be cultivated again without competing with food and fodder crops or other products,” explained Dr. Lask. Once established as a permanent crop, miscanthus not only reduces the risk of erosion and stabilizes the soil, it also effectively suppresses the growth of weeds.
Not only a promising energy crop
According to the researchers’ calculations, bioethanol production from miscanthus in combination with carbon storage can contribute significantly to reducing greenhouse gas emissions in the European transport sector: Depending on the approach for calculating biological carbon storage used, a reduction of more than 100 percent compared to the EU benchmark for fossil fuels is thus likely—meaning there can even be a negative CO2 balance.
Despite their enthusiasm for the possibilities of bioeconomy, the partners also want to test whether there could be negative effects for people and the environment and which intensity of biomass cultivation is safe and sensible. A possible negative effect would be if more intensive cultivation of biomass were to force out other uses of the land, for example. In the best case scenario, jobs would be created, especially in areas of Croatia that have been deserted since the Balkan conflict.