A conceptual comparison of bioenergy options for using mountain pine beetle infested wood in Western Canada Amit Kumar * Department of Mechanical Engineering, University of Alberta, 4-9 Mechanical Engineering Building, Edmonton, Alberta, Canada T6G 2G8 article info Article history: Received 22 January 2007 Received in revised form 27 April 2008 Accepted 30 April 2008 Available online 9 July 2008 Keywords: Beetle killed trees Biopower Bio-oil Bio-ethanol Techno-economic assessment abstract Biomass is nearly carbon neutral and can be used for the production of various liquid fuels and chemicals. Decisions on biomass utilization should be based on the most economical and mature route. This study analyzes mountain pine beetle (MPB) killed wood as the feedstock for production of bio-ethanol and bio- oil and compares it with the direct combustion route to produce electricity. The MPB infestation of British Columbia’s (BC), a western province of Canada, forest has reached an epidemic proportion and is spread over an area of 10 million ha. According to the current estimates of BC‘s Ministry of Forests and Range, about 1 billion m 3 of trees would be killed by MPB by 2013. This infestation would result in large scale loss of jobs and the standing dead trees are a fire hazard and if left unharvested will decay and release carbon back to the atmosphere. The cost of bio-ethanol production from a 2100 dry tonne/day plant using the infested wood for two locations (one remote and other near the industry) in BC is in the range of C$0.37–C$0.40/l (C$1.40–C$1.51/gallon). Similarly, cost of bio-oil production from a 220 dry tonne/day plant using the infested wood for same two locations in BC is in the range of C$0.27–C$0.29/l (C$1.02– C$1.09/gallon). The cost of producing electricity using this bio-oil is above C$100/MWh which is higher than the current power price in BC. This cost is also higher than the cost of production of electricity by direct combustion of infested wood in a boiler (C$68–C$74/MWh). Ó 2008 Elsevier Ltd. All rights reserved. 1. Background and overview Biomass is a renewable fuel and is considered nearly carbon neutral. There are myriad of applications for its usage and it is important to evaluate different bioenergy options. Apart from the use of biomass for electricity production, it can be used to pro- duce liquid fuels such as bio-ethanol and bio-oil. It is important to evaluate various options before making an investment decision. This paper is a comparison of the following three bioenergy op- tions for using mountain pine beetle infested wood: electricity production by direct combustion; bio-ethanol production by hydrolysis and fermentation; and, bio-oil production by fast pyrolysis. British Columbia (BC) is one of the western provinces of Canada. Large areas of the province are covered by forest. Therefore, forest industry is one of the main revenue generating industry in the province. BC’s forest consists of coniferous (lodgepole pine, douglas fir, spruce, hemlock, cedar, and true firs) and deciduous tree spe- cies. Currently, the forest industry is facing a huge problem of infestation by mountain pine beetle. This beetle attacks mostly mature (80–100 years old) lodgepole pine by feeding on the sap- wood of the tree. The attack also has a symbiotic relationship with blue stain fungi that causes paralysis of immune system of the trees (Pacific Forestry Centre, 2005). According to the current esti- mates of BC Ministry of Forest and Range (MOFR), the infestation is expected to kill approximately 960 million m 3 of tree by 2013 (Clark, 2005) and it is expected that at least 200–600 million m 3 of wood would remain unharvested by 2013 (MoFR, 2003). Already by summer of 2005, an area of 10 million ha was infested (Clark, 2005). This infestation will result in large scale loss of jobs in the forest industry and is also a potential fire hazard. If the infested for- est is not harvested, it will decay and release carbon to the atmo- sphere (Cote et al., 2002). Utilization of this biomass resource for energy can mitigate these problems. Bio-ethanol is the name given to the ethanol produced from biomass. Biomass feedstock can include a wide range of materials such as corn, bagasse, agricultural residues (straw or corn stover) or woody biomass (softwood or hardwood). Production of alcohol is not a new concept. Many plants around the world produce bio-ethanol from corn. Annual production capacity of ethanol in the United States is about 4330 million gallons/yr (Ethanol Produc- ers and Consumers, 2006) and additional capacity of 1750 million gallons/yr is under construction and expansion. In Canada about 63 million gallons of bio-ethanol is produced annually (Agriculture and Agri-Food Canada, 2001). Most of the bio-ethanol produced to- day is based on grain. Research is in progress in the area of produc- tion of bio-ethanol from woody biomass. Several authors have 0960-8524/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.biortech.2008.04.077 * Tel.: +1 780 492 7797; fax: +1 780 492 2200. E-mail address: Amith.Kumar@ualberta.ca Bioresource Technology 100 (2009) 387–399 Contents lists available at ScienceDirect Bioresource Technology journal homepage: www.elsevier.com/locate/biortech