Energy efficiency of ethanol production from cellulosic feedstock

Biofuel can be a potential supplement to fossil fuel and help in meeting increasing energy demand of the USA as well as rest of the world. However, it is important for the biofuel to be economically competitive and energy efficient to be established as a promising energy source. There has always been an argument about energy efficiency of biofuel production. Some studies have claimed that it requires more energy to produce ethanol then it actually produces as an output. The objective of the study is to determine energy efficiency of growing two potential cellulosic feedstock; switchgrass and Miscanthus and conversion them in to cellulosic ethanol. Energy efficiency was determined by calculating Net Energy Value (NEV), the difference between output energy obtained by ethanol and input energy used in producing ethanol. Input energy consisted of energy required to produce the cellulosic biomass, transporting it to the ethanol processing facility and processing cellulosic biomass in to ethanol. The analysis showed positive The NEV for both switchgrass and Miscanthus. NEV for Miscanthus (12.41 MJ/l of ethanol) was higher in compared to the switchgrass (7.90 MJ/l of ethanol). Monitory benefits of energy savings were also estimated to determine the impact of energy saving to the society. Results from this research showed both switchgrass and Miscanthus as potential biomass feedstock for cellulosic ethanol production. Published by Elsevier Ltd.