Production costs and residues evaluation of Crambe abyssinica as an energy feedstock

abyssinica grown in two variants (with and without herbicides). In addition, the quality of by-products (straw and cake) as energy feedstocks was evaluated. Costs of production of Crambe abyssinica seeds in the variant with herbicides were nearly 140€·ha-1 higher than in the variant without herbicides. The yield of pure seeds was by over 110kg·ha-1 higher in the herbicidetreated variant than in the treatment without weed control. However, the yield of straw was higher on fields without application of herbicides, but that straw had a higher moisture content due to the presence of weeds. The lower heating value of crambe straw was 15.3MJ·kg-1 on average and the straw content of ash was 5.68% D.M. The cake obtained from the crop had a much higher lower heating value (21.95MJ·kg-1) and ash content 6.41% D.M. Moreover, it was found to contain much more carbon and hydrogen, as well as five-fold more sulfur than straw. Production costs and residues evaluation of Crambe abyssinica as an energy feedstock*