Understanding the Canadian oil sands industry's greenhouse gas emissions

The magnitude of Canada's oil sands reserves, their rapidly expanding and energy intensive production, combined with existing and upcoming greenhouse gas (GHG) emissions regulations motivate an evaluation of oil sands-derived fuel production from a life cycle perspective. Thirteen studies of GHG emissions associated with oil sands operations are reviewed. The production of synthetic crude oil (SCO) through surface mining and upgrading (SM&Up) or in situ and upgrading (IS&Up) processes is reported to result in emissions ranging from 62 to 164 and 99 to 176 kgCO(2)eq/bbl SCO, respectively (or 9.2-26.5 and 16.2-28.7 gCO(2)eq MJ(-1) SCO, respectively), compared to 27-58 kgCO(2)eq/bbl (4.5-9.6 gCO(2)eq MJ(-1)) of crude for conventional oil production. The difference in emissions intensity between SCO and conventional crude production is primarily due to higher energy requirements for extracting bitumen and upgrading it into SCO. On a 'well-to-wheel' basis, GHG emissions associated with producing reformulated gasoline from oil sands with current SM&Up, IS&Up, and in situ (without upgrading) technologies are 260-320, 320-350, and 270-340 gCO(2)eq km(-1), respectively, compared to 250-280 gCO(2)eq km(-1) for production from conventional oil. Some variation between studies is expected due to differences in methods, technologies studied, and operating choices. However, the magnitude of the differences presented suggests that a consensus on the characterization of life cycle emissions of the oil sands industry has yet to be reached in the public literature. Recommendations are given for future studies for informing industry and government decision making.