WASHINGTON – Building the Keystone XL pipeline could lead to as much as four times more greenhouse gas emissions than the State Department has estimated, according to a study published in the journal Nature Climate Change that uses different calculations about oil consumption.
Emissions of heat-trapping carbon dioxide became central to the Obama administration’s review of a federal permit for Keystone XL after the president announced in June 2013 that he would let the controversial project proceed only if “it does not significantly exacerbate the problem of carbon pollution.”
The study’s authors based their calculations on the premise that increased supplies of petroleum through the pipeline would push down global oil prices marginally, and that would lead to an increase in consumption and thus pollution.
“We find that for every barrel of increased production, global oil consumption would increase 0.6 barrels owing to the incremental decrease in global oil prices,” the study said.
In its final environmental impact statement last February, the State Department estimated that the proposed pipeline, which would ultimately carry 830,000 barrels of oil daily, could increase emissions of heat-trapping greenhouse gases by 1.3 million to 27.4 million metric tons annually.
The new study estimates that emissions could be 100 million to 110 million metric tons every year, “or four times the upper State Department estimate,” the authors wrote.
“The sole reason for this difference is that we account for the changes in global oil consumption resulting from increasing oil sands production levels, whereas the State Department does not,” wrote authors Peter Erickson and Michael Lazarus, scientists based in Seattle with the Stockholm Environment Institute, a nonprofit research organization.
The $5.3 billion pipeline would run from Hardisty, Alberta, to Steele City, Neb., where it would tie into a southern leg that has already been built and that runs to refineries along the Texas Gulf Coast.
Because the project crosses the U.S. border with Canada, it needs a federal permit.
The State Department concluded in its final environmental impact statement that Keystone XL would not lead to greater greenhouse gas emissions because it would not spur a marked increase in production of petroleum from Alberta’s oil sands.
The State Department determined that increased rail capacity and other proposed pipelines would deliver the oil even if the pipeline were not built.
Although rail usage is growing, it remains a more expensive option. Further, other proposed pipeline projects from Alberta to the East and West Coasts have been slowed by local resistance.
Last month, the city of South Portland in Maine voted to ban the export of crude oil from its waterfront, effectively barring the possibility of reversing the flow of an existing import pipeline into Canada to ship crude out of the country.
In June, the Canadian Association of Petroleum Producers issued an annual outlook that scaled back projections for growth in oil sands output, in part because of delays in pipeline projects, including Keystone XL.
The slowdown seems at odds with the State Department’s conclusion that green-lighting Keystone XL would have little effect on production and, with it, the emissions that stoke climate change.
In April, the Obama administration said it would delay its decision on granting a permit to the pipeline because of a Nebraska court decision invalidating part of the project’s route. The Nebraska Supreme Court will review the case this fall.