Title: A life cycle greenhouse gas emissions perspective on liquid fuels from unconventional Canadian and US fossil sources

Authors: Jennifer M. McKellar, Alex D. Charpentier, Joule A. Bergerson, Heather L. MacLean

Addresses: Department of Civil Engineering, University of Toronto, 35 St. George St., Toronto, ON, M5S 1A4, Canada. ' Department of Civil Engineering, University of Toronto, 35 St. George St., Toronto, ON, M5S 1A4, Canada. ' Department of Chemical and Petroleum Engineering, ISEEE, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N 1N4, Canada. ' Department of Civil Engineering, University of Toronto, 35 St. George St., Toronto, ON, M5S 1A4, Canada

Abstract: The life cycle Greenhouse Gas (GHG) emissions associated with the production and use of transportation fuels from conventional and unconventional fossil fuel sources in Canada and the USA are investigated. The studied pathways include reformulated gasoline and low sulphur diesel produced from oil sands, oil shale, coal and natural gas, as well as reference pathways from conventional crude oil. comparison of Life Cycle Assessments (LCAs) completed for these fuels indicates considerable uncertainty in these emissions, illustrating the need for further LCAs with particular attention to completeness and transparency. Based on the considered studies, only one unconventional pathway has better GHG emissions performance than the conventional pathways: Fischer-Tropsch diesel from natural gas. However, the limitations of the data used here and other factors that may restrict a switch to natural gas must be considered. Furthermore, there are considerable opportunities to reduce emissions from the unconventional pathways. There is significant potential to produce liquid transportation fuels from unconventional Canadian and US fossil sources. However, to avoid significant increases in GHG emissions, the life cycle GHG implications of almost all pathways will need to be reduced to respond to upcoming regulatory initiatives and to move towards a more sustainable transportation sector.

Keywords: oil sands; oil shale; coal-to-liquids; CTL; gas-to-liquids; GTL; natural gas; life cycle assessment; LCA; greenhouse gases; GHG emissions; transportation fuels; global warming; fossil fuels; Canada; USA; United States; reformulated gasoline; low sulphur diesel; sustainable transport; sustainability; sustainable development.

DOI: 10.1504/IJGW.2009.027087

International Journal of Global Warming, 2009 Vol.1 No.1/2/3, pp.160 - 178

Published online: 14 Jul 2009 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article