The first dedicated independent study into the miscanthus carbon life cycle shows that the crop is net carbon negative, capturing net 0.64 tonnes of carbon (2.35 tonnes CO2e) per hectare, per year in the soil at the very least.
The peer-reviewed study substantiates the two known simultaneous carbon cycles of miscanthus, where the above ground biomass grows each year and recycles all the carbon that’s been produced through planting, harvesting and burning the crop for renewable electricity, and at the same time, the underground rhizome and decaying leaf litter fixes and stores carbon each year as it grows.
The results are crucial for farmers looking at carbon farming opportunities, and for the rapidly emerging bioeconomy, because there has been a lack of evidence-based research into carbon sequestration capabilities of crops, until now, according to the firm releasing the research, Miscanthus specialist, Terravesta, in collaboration with the University of Honenheim, and the international research project, GRACE (GRowing Advanced industrial Crops on marginal lands for biorEfineries).
The carbon sequestration research was conducted by Jan Lask, from the University of Hohenheim. The study separately considers the carbon relative to the growing crop in the field, attributable to the land, under net carbon capture, and the carbon associated with the biomass and its uses, under crop biomass.
“The results are conservative, and in reality, the carbon sequestration potential may be higher, and it will change from site to site,” says Jan.
“We looked at the above ground and below ground carbon life cycles separately, and calculated the carbon stored in the biomass and in the rhizome, and we also measured the miscanthus leaf litter that decomposes over time and becomes incorporated into the soil, contributing to the soil carbon.”
Miscanthus is already established on over 7,000 hectares of marginal land and counting in the UK, and is thought to have the potential to contribute significantly to the UK’s 2050 net zero target. It’s said to be a scalable solution that’s operational now, beneficial to the environment and profitable for farmers.
Dr Jason Kam, Terravesta research and development manager, outlines the reasons for conducting the study. “There has been a lack of understanding on how carbon is evaluated, and many unsubstantiated figures used,” he says. “The need to resolve this will be crucial in delivering the industrial, economic and societal changes needed to build a sustainable future.”