Life cycle greenhouse gas analysis of bioenergy generation alternatives using forest and wood residues in remote locations: A case study in British Columbia, Canada

Abstract

Utilization of forest and wood residues as bioenergy feedstock in some remote communities could reduce environmental burdens and increase development opportunities. In a thorough bioenergy project planning, in addition to the economic performance, the potential greenhouse gas (GHG) emissions from investment alternatives should be considered. We present an economic assessment and a life cycle analysis of GHG emissions of alternative bioenergy systems, which include four combustion and gasification technologies with different capacities (0.5 MW, 2 MW and 5 MW), in two remote communities in British Columbia, Canada. In the analysis, all stages from harvesting to energy production are included, and the GHG emissions of the baseline system in each community (the current situation with all the products and services it provides) is used as the reference for comparison. Results of this study show that for small scale alternatives (0.5 MW and 2 MW), cogenerating plants using boiler/steam turbines generate the cheapest electricity, while for larger scale alternatives (5 MW), the most economical plant alternative is a gasification cogeneration system. In the community where all energy needs are currently satisfied using fossil fuels, and all biomass residues (forest and sawmill residues) are currently disposed by burning, net reductions of up to 40,909 t of CO 2 equivalent GHG emissions could be achieved with the installation of a 5 MW boiler/steam turbine cogenerating heat and electricity. In the community where the current energy mix is mostly supplied from other renewable sources (i.e. hydro), and where forest residues are disposed by burning and sawmill residues are landfilled, the net GHG emission reductions that can be achieved with a bioenergy system are considerably lower (2,535 t of CO 2 equivalent emissions with a 5 MW cogenerating gasification system) or null, since the carbon capture of current biomass disposal in landfill outweighs the carbon emission reduction of most bioenergy alternatives.

Environmentally optimal wood use in Switzerland—Investigating the relevance of material cascades

“…The method chosen by most studies to assess environmental impacts of wood processing and wood products is life cycle assessment (LCA) (Werner and Richter, 2007;Rüter and Diederichs, 2012;Sathre and González-García, 2014;Cambero et al, 2015). Klein et al (2015) reviewed LCA studies of wood production and utilisation published in the past 20 years and concluded that, despite significant differences in the results, LCA is a well-established methodology to assess environmental impacts of the wood value chain.…”

Biomass Residues to Renewable Energy: A Life Cycle Perspective Applied at a Local Scale

“…Furthermore, Paredes-Sánchez et al [26] studied the valorization of residues in Asturias, Spain, where the use of biomass offers the opportunity to create a new path to economic development with a reduction of CO2 emissions. A similar topic has been discussed, regarding the wood residues in British Columbia (Canada) [27]: for small scale community cogenerating plant the use of wood residues generated the As depicted, the use of wood residues leads to considerable benefits in terms of climate change (considering a 100-years perspective) and of fossil fuels depletion, −41% and −40%, respectively. Similar GHGs mitigation trend was already outlined by previous works [7,8], which suggested the importance of using wood-based appliances to reduce climate change effects.…”

“…Furthermore, Paredes-Sánchez et al [26] studied the valorization of residues in Asturias, Spain, where the use of biomass offers the opportunity to create a new path to economic development with a reduction of Energies 2016, 9, 922 10 of 15 CO 2 emissions. A similar topic has been discussed, regarding the wood residues in British Columbia (Canada) [27]: for small scale community cogenerating plant the use of wood residues generated the cheapest electricity. Wolf et al [7], studying the energetic use of wood in a German region, outlined that the magnitude of mitigation can vary greatly depending on the current thermal energy mix.…”

A critical review on biomass gasification, co-gasification, and their environmental assessments

“…Life cycle analyses of GHG emissions of bioenergy systems including combustion and gasification technologies -with different capacities -in British Columbia were investigated by Cambero et al (2015). Their results implied that in the community where all energy needs were satisfied with fossil fuels and biomass residues were disposed of by burning, net reduction of up to 40,909 t of CO2 equivalent GHG emissions could be achieved.…”