New energy crop giant cane (Arundo donax L.) can substitute traditional energy crops increasing biogas yield and reducing costs

Giant cane is a promising non-food crop for biogas production. Giant cane and corn silages coming from full-scale fields were tested, in mixtures with pig slurry, for biomethane production by a continuous stirred tank lab-scale-reactor (CSTR) approach. Results indicated that giant cane produced less biomethane than corn, i.e. 174 +/- 10 N m(3) CH4 Mg (1) TS (1) and 245 +/- 26 N m(3) CH4 Mg (1) TS (1), respectively. On the other hand, because of its high field biomass production, the biogas obtainable per Ha was higher for giant cane than for corn, i. e. 12,292 N m(3) CH4 Ha (1) and 4549 N m(3) CH4 Ha (1), respectively. Low energetic and agronomic inputs for giant cane cultivation led to a considerable reduction in the costs of producing both electricity and biomethane, i. e. 0.50 (sic) Nm (3) CH4 (1) and 0.81 (sic) Nm (CH41)-C-3, and 0.10 (sic) kW h(EE)(1) and 0.19 (sic) kW h(EE)(1) for biomethane and electricity production, and for giant cane and corn mixtures respectively. (C) 2015 Elsevier Ltd. All rights reserved.