Study says Keystone XL would raise greenhouse-gas emissions four times more than top federal estimate

A study published in the journal Nature Climate Change says the controversial Keystone XL pipeline could increase greenhouse-gas by as much as 110 million metric tons every year, about four times more than the maximum estimate of the State Department, Neela Banerjee reports for the Los Angeles Times. (Washington Post graphic)

In February the department estimated that the 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," Banerjee writes. Authors of the study say their numbers are higher are because "We account for the changes in global oil consumption resulting from increasing oil-sands production levels, whereas the State Department does not.” 

"The study’s authors based their calculation 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," Banerjee writes. The study said, "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." (Read more)

In April the department said it was delaying its final decision on the pipeline until it could get a better idea on how legal challenges to the route in Nebraska will be settled. A judge said in February that when legislators allowed Gov. Dave Heineman to decide the route, rather than the Nebraska Public Service Commission, they violated the state constitution.