Feasibility of Biogas Production from Napier Grass

The current study focused on the feasibility of biogas production from Napier grass. Napier grass, a tropical plant, can grow up in drought and dry conditions. Napier grass contains 30.9% total carbohydrates, 27% protein, lipid 14.8%, total ash 18.2%, fiber 9.1% (dry weight). Its organic compositions are an ideal feedstock for biogas production. The fresh grass was harvested after 5 week plantation, grounded in 0.5 to 1 mm diameter size before fermentation in mesophilic batch reactors, with varying solid concentrations of 5 - 15 %. The optimum condition for the biogas production was found at 5% solid concentration. Methane content, yield and production rate were 53%, 122.4 mL CH4/g TVS remove, 4.8 mL/ht at the optimum condition. Economic analysis of biogas obtained from the experiment with liquid petroleum gas (LPG) with benefit/cost ratio (B/C ratio) greater than 1 suggested that the Napier grass is considered as a potential energy crop. (C) 2014 The Authors. Published by Elsevier Ltd.