Tar Sands and GHG Emissions: Setting the Record Straight

As I laid out in a previous blog, after years of academic studies and environmental impact statements showing tar sands being significantly dirtier that conventional crude oils, the government of Alberta and the oil industry are fighting back with their own consultant studies.

The latest salvo from the oil industry comes from IHS CERA’s report “Oil Sands, Greenhouse Gases, and U.S. Oil Supply,” purporting that a review of the literature shows tar sands emit  “only” 5 to 15% more emissions.[1]   However, in reviews conducted by NRDC in 2008 and 2010 on much of the same body of literature,[2] the results showed a range of 8 to 37% greater emissions.[3]   

This Wednesday (November 17th), IHS CERA comes to Washington, D.C. as part of the overarching campaign being waged by the industry and Alberta government to clean-up their image. The strategy has mainly been to argue that emissions from tar sands are not as bad as previously thought and that the industry will clean-up over time, a myth my colleague Susan Casey-Lefkowitz has debunked. This battle over perception however is reflective of a much larger, broader campaign now being waged to prevent the U.S. from adopting policies like a low carbon fuel standard that would significantly reduce U.S. oil dependency and hence, the need for Canadian tar sands.

Policymakers should rightfully remain wary of CERA’s message in terms of GHG emissions and tar sands, particularly given the lack of transparency in their report.  Instead, policymakers should ensure we truly level the playing field for the fuels market and account for the environmental impact of our infrastructure investment decisions, such as with the Keystone XL pipeline. At minimum, all petroleum fuels should be  held to the same level of evaluation and lifecycle reporting that is now the norm for alternative fuels. A full and complete lifecycle analysis should be performed for high carbon intensity crude oils, overseen by a neutral advisory committee of academics and neutral government agency officials wihout ties to vested oil interests.

Below, some of the problems of relying on the industry to come up with its own environmental assessments are shown.  (Some of the likely reasons for the low estimates from CERA that are summarized below are covered in this more detailed NRDC study.)

  • Mixing tar sands with other fuel sources: CERA considers mixed barrels of bitumen (tar sands) and natural gas condensates (called diluent). Because the emissions from the latter source are so much lower, mixing the two sources effectively lowers the apparent impact of Canadian tar sands. This approach is also used in several other studies relied upon by CERA.[4] Instead of reporting the results separately in terms of gasoline produced from bitumen and gasoline derived from natural gas liquids, the approach mixes the crude oil and natural gas sources, effectively making bitumen emissions appear lower by about 6% on a well-to-wheels basis.
  • Assumes lower amounts of steam used than the current industry average: Heating up the ground to extract a barrel of bitumen takes a lot of thermal energy (by way of steam). Current practices in industry range from 2 to 7 units of steam to produce each unit of oil (or steam-oil-ratio, SOR).  CERA cites the use of a SOR of 3, while several of the studies referenced by CERA consider cases where the SOR is either 2.5 or 3.[5] However, the current industry average steam usage is about 20% higher than the value used by CERA, at about 3.6 SOR rather than 3. Our estimate is that adjusting CERA results from 3 to 3.6 SOR would result in an additional 3% increase in lifecycle emissions.
  • Omits Direct Land Use Change Emissions:  Emissions from the removal of vegetation and trees, soil, and peatland are significant particularly for mining practices and should be included. In a study involving five major Canadian and U.S. universities, Yeh et al (2010) estimated that surface mining of tar sands resulted in between a 0.9 to 2.5% increase in the lifecycle emissions versus the U.S. average baseline. CERA recognizes that direct land use emissions could increase their estimate for surface mining by as much as 6% on a lifecycle basis but did not include these emissions in their calculations.
  • Fugitive emissions:  Fugitive emissions can come from sources such as leaks as well as from practices such as the creation of tailing ponds which release methane (CH4). The CERA report does not appear to add fugitive emissions into its estimates although this is difficult to verify. Some of the sources CERA relies upon include an emissions factor while others do not. Yeh et al (2010) estimated that fugitive emissions from tailing ponds (mining) could add 0 to 9% emissions compared to the baseline.[6] The representative value reported by Yeh et al (2010) would result in an additional 2.8% increase in lifecycle emissions.
  • Venting and Flaring Emissions:  Venting and flaring emissions are not included in a number of the source studies relied upon by CERA, such as CAPP (2008), RAND (2008), and the U.S. Department of Energy’s GREET lifecycle model.[7] It is unclear whether CERA applied a factor for these emissions. Nevertheless, TIAX (2009) estimated that the range of between 0.5 g/MJ (for mining) to 3.3 g/MJ (for in-situ) would result in a 0.5 to 3.6% increase in well-to-wheel emissions versus the baseline.   
  • Emissions from Production of Natural Gas and Electricity: CERA states that indirect emissions are not included in its evaluation. Significant amounts of emissions can be associated with imports of natural gas, electricity, and other products. The Jacobs (2009) study estimated that the inclusion of these emissions would add about 4.3 to 5.7% to total lifecycle emissions.

So Why Should We Care About Emissions from Tar Sands? It’s because the current expansion of tar sands is potentially so large that it threatens to displace the gains the U.S. has made from the clean fuels industry, locking us into multi-decade investments that will keep us addicted to even dirtier forms of crude oil. 

To place it into context: The oil industry’s investments in dirty fuels production threatens to swamp all our clean fuel investments and then some, including those made by the advanced biofuels industry, from automakers producing plug-in electric vehicles, and from owners of truck and bus fleets converting from diesel to run on natural gas.    

All told, the U.S. oil industry is pushing to expand consumption of tar sands from 800,000 barrels per day (bpd) to 3,100,000 barrels through the development of the Keystone XL and Alberta Clipper pipelines over the next five to ten years. By 2025, the Canadian Association of Petroleum Producers forecasts production will grow to nearly 4 million barrels per day with most of this coming to the U.S. 

By comparison, the U.S. Renewable Fuels Standard (RFS) will result in 2.3 million bpd of biofuels when fully enacted.  At nearly twice the volume, the expansion of tar sands threatens to increase emissions by about 150 million tons of CO2-equivalent per year, more than enough to offset the CO2 reductions from the RFS as well as some of the benefits from vehicle efficiency.

We should be taking a hard look at not only GHG emissions from tar sands but at the direction the oil industry wants to take America.  The Low Carbon Fuel Standard – being enacted in California, the Northeast, Mid-Atlantic, other states and Europe – makes sure we move forward and not backwards, helping America  phase in cleaner fuels and phase out the dirtier ones.

[1] http://www2.ihscera.com/docs/Oil_Sands_Energy_Dialogue_0810.pdf

[2] Mui, S., D. Hannah and R. Hwang (2008), Life Cycle Analysis of Greenhouse Gas Emissions from Tar Sands, Natural Resources Defense Council, November 18, 2008; S. Mui, L. Tonachel, B. McEnaney, and E. Shope, GHG Emission Factors for High Carbon Intensity Crude Oils.

[3] The U.S. average 2005 gasoline and diesel baseline was determined by the U.S. Environmental Protection Agency together with the U.S. Department of Energy. For reference, see EPA (2010), Renewable Fuel Standard Program (RFS2): Regulatory Impact Analysis. February 2010, EPA-420-R-10-006.

[4] TIAX (2009), Comparison of North America and Imported Crude Oil Lifecycle GHG Emissions, Final Report, TIAX LLC and MathPro Inc, prepared for Alberta Energy Research Institute., Jacobs (2009), Life Cycle Assessment Comparison of North American and Imported Crudes, Jacobs Consultancy and Life Cycle Associates, prepared for the Alberta Energy Research Institute.

[5] TIAX (2009) and Jacobs (2009).

[6] Sonia Yeh et al. (2010), “Land Use Greenhouse Gas Emissions from Conventional Oil Production and Oil Sands, Environ. Sci. Tech. Accepted September 14, 2010.

[7] CAPP (2008), Environmental Challenges and Progress in Canada’s Oil Sands, Canadian Association of Petroleum Producers; RAND Corporation (2008), Unconventional Fossil-Based Fuels: Economic and Environmental Trade-Offs.

About the Authors

Simon Mui

Director, California Vehicles and Fuels, Energy & Transportation program

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