Life cycle assessment of ethanol derived from sawdust Poritosh Roy ⇑ , Animesh Dutta ⇑ School of Engineering, University of Guelph, Ontario N1G 2W1, Canada highlights  The life cycle of ethanol derived from sawdust is evaluated considering two scenarios.  The net energy consumption, CO 2 emission and production cost are estimated.  Competitiveness of production cost remains doubtful unless Feed-in Tariff (FiT) is considered. article info Article history: Available online 14 August 2013 Keywords: Sawdust Ethanol Life cycle assessment (LCA) Net energy consumption GHG emissions abstract The life cycle of ethanol derived from sawdust by enzymatic hydrolysis process is evaluated to determine if environmentally preferable and economically viable ethanol can be produced. Two scenarios are con- sidered to estimate net energy consumption, greenhouse gas (GHG) emission and production costs. The estimated net energy consumption, GHG emission and production costs are 12.29–13.37 MJ/L, 0.75– 0.92 kg CO 2 e/L and about $0.98–$1.04/L, respectively depending on the scenarios of this study. The result confirmed that environmental benefit can be gained with present technologies; however, economic via- bility remains doubtful unless Feed-in Tariff (FiT) is considered. The production cost of ethanol reduces to $0.5/L, if FiT is considered to be $0.025/MJ. This study indicates that the implementation of FiT program for ethanol industry not only helps Ontario mitigate GHG emissions, but may also attract more invest- ment and create rural employment opportunities. Ó 2013 Elsevier Ltd. All rights reserved. 1. Introduction The growing concerns about climate change, rising costs of fos- sil fuels and the geo-political uncertainty associated with possible interruption of current fossil fuel-based energy supplies have moti- vated nations to seek clean and renewable substitutes to reduce their greenhouse gas (GHG) emission. Renewable energy reduces the reliance on foreign oil, improves energy security, provides sig- nificant environmental benefits and enlarges rural economies. Lig- nocellulosic ethanol is a widely recognized alternative to fossil gasoline, and its production and use have been emphasized be- cause it is highly reproducible and does not compete with food. According to the Renewable Energy Regulation (SOR/2010-189), Canadian fuel producers and importers of gasoline require to have renewable fuel content of at least 5% of distillates (by volume) that they produce and import yearly (Environment Canada, 2010), which creates huge demand, especially on lignocellulosic ethanol. The potential sources of renewable biomass in Canada include waste products from forestry and agricultural residues, municipal solid waste, and energy crops. In Canada, the amount of lignocellu- losic biomass production is reported to be approximately 9.4  10 6 t/year. Residual lignocellulosic feedstock could provide up to 50% of Canada’s 2006 transportation fuel demand (Mabee and Saddler, 2010). Forestry products, particularly sawdust, forest thinning and trimming are potential feedstock for ethanol produc- tion (Kadam et al., 2000; Mu et al., 2010). The life cycle GHG emis- sions from biofuels and their ability to reduce GHG emission are dependent on choice of feedstock, agricultural practices, and con- version technologies with differing socioeconomic and environ- mental impacts (Luo et al., 2009; Kaufman et al., 2010). Although many researchers have evaluated the life cycle of lignocellulosic ethanol produced by enzymatic hydrolysis process, ethanol from sawdust received only limited attention (Slade et al., 2009; Sandi- lands et al., 2009), their research deals with thermochemical con- version (gasification-synthesis). This study evaluated the life cycle of ethanol produced by enzymatic hydrolysis and considered two scenarios to determine if environmentally preferable and eco- nomically viable ethanol can be produced from sawdust in Ontario, Canada. 2. Methodology Life cycle assessment (LCA) is a tool that evaluates the environ- mental impacts of each stage of a product, process or activity’s life. LCA is widely used to evaluate environmental performance of 0960-8524/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.biortech.2013.08.057 ⇑ Corresponding authors. Tel.: +1 519 824 4120x52441; fax: +1 519 836 0227. E-mail addresses: poritosh@uoguelph.ca (P. Roy), adutta@uoguelph.ca (A. Dutta). Bioresource Technology 150 (2013) 407–411 Contents lists available at ScienceDirect Bioresource Technology journal homepage: www.elsevier.com/locate/biortech