Carbon from oil sands growing, but not ‘game over’
Want a real climate villain? Try coal
Some oil sands critics assert that oil sands development is “game over” for the world’s climate. James Hansen, a NASA scientist, argues that oil sands development would increase the concentration of carbon dioxide (CO2) in the Earth’s atmosphere by 120 parts per million, or ppm (his value was a revision from an earlier estimate that put the number as high as 200 ppm).
Assuming that each oil sands barrel has life cycle greenhouse gas (GHG) emissions of 517 kilograms of CO2 equivalent (life cycle emissions include carbon from extracting, refining, transporting and ultimately consuming the fuel), then 1.7 trillion oil sands barrels must be produced before 120 ppm of carbon equivalent would be added to the world’s atmosphere.
This is impossible. With existing production methods, only 10 per cent, or 170 billion barrels, of the entire oil sands resource can be produced economically. Even if you assume that higher recovery rates are possible, then about 315 billion barrels is a more likely ultimate production volume; this would be equivalent to about 20 ppm of carbon dioxide equivalent in the Earth’s atmosphere or 17 per cent of Hansen’s estimate.
However, the choice of crude type (oil sands or conventional oil, for instance) is less important than the volume of crude oil the world ultimately consumes, since 70 to 80 per cent of the total life cycle emissions result from the combustion of fuel, such as gasoline.
Combustion emissions do not vary with the crude oil used to produce the fuel. If you assume that, in the absence of oil sands development, the world consumes the same volume of oil, then oil sands’ real contribution to global GHG emissions is even less significant. Instead of adding 20 ppm of carbon dioxide equivalent to the Earth’s atmosphere, the value is under one ppm (or less than one per cent of Hansen’s estimate).
In fact, the oil sands are far from the largest source of GHGs in the world, or even in Canada. In 2010, oil sands production made up less than 0.2 per cent of global GHG emissions, or seven per cent of Canada’s emissions.
Domestically, emissions from transportation (28 per cent), total emissions from the energy extraction sector (27 per cent), of which the oil sands account for seven per cent, and electrical generation (15 per cent) each constitute a larger portion of total Canadian emissions than oil sands production.
And even if oil sands emissions are removed from the annual totals, between 1990 and 2010 Canadian GHG emissions still grew by 12 per cent. In other words, Canada would not have met its GHG emission reduction targets under the Kyoto Protocol (the accord called for a six per cent decrease by 2012, compared to 1990 levels) irrespective of the oil sands.
Still, oil sands-related emissions could climb from seven per cent of the Canadian total today to between 14 to 21 per cent by 2030 (a low case development scenario assumes 3.1 million barrels per day of production, while the high case assumes 5.7 million barrels per day of production).
While the GHG intensity of each barrel of oil sands production is assumed to decline, growth in the number of barrels produced is expected to exceed efficiency gains, resulting in emissions growth. By 2030, in the high case development scenario, emissions from oil sands could be near or at par with Canada’s electrical generation sector, but still lower than emissions from the transportation sector. In absolute terms, the emissions resulting from oil sands by 2030 could range from the equivalent of 70 to 160 million tonnes of CO2.
How do emissions from oil sands compare with other sources? The U.S. currently produces six million barrels per day of crude oil domestically, creating the equivalent of about 55 million tonnes of CO2 each year. Natural gas-fired electricity generated in the U.S. results in more than 360 million tonnes of CO2 equivalent per year. U.S. emissions from transport and for generating electricity from coal each total about 2,000 million tonnes of CO2 yearly. Ask yourself, then: Which is the real “carbon bomb”?