SEQUENTIAL cropping can produce additional biomass without negative impacts on land use or food production, according to the Italian Biogas Consortium.
In Europe, agricultural land is often left fallow during winter time, but Ecofys researchers have claimed that the right winter cover crop cultivated in addition to the usual summer crop can boost the productivity of the main crop, alongside delivering the additional income from the biomass.
Research focussed on a case study in Northern Italy, where maize silage was cultivated as a summer crop for animal feed, and triticale silage was grown as an additional winter crop for biogas, with the digestate residue fed back to the fields.
The researchers investigated how much additional biomass was produced and which impacts occurred on soil nutrients, soil erosion, water availability, on-farm biodiversity and the carbon balance, using a methodology developed for the European Commission.
The results suggested that the crop mix was promising – crop yields for animal feed and additional biogas feedstock were both increased, providing additional income to farmers without displacing existing feed production or creating other negative environmental impacts.
“Seeing that low cost biomethane can be produced with positive environmental impacts and no negative land use change risks is encouraging, as biofuels are needed in much greater quantities than today to decarbonise the transport sector," said bioenergy consultant Daan Peters. "It would be exciting to see whether this concept can be rolled-out throughout Europe.”