Carbon dioxide emissions from the proposed Keystone XL pipeline and the Canadian oil sands are far higher than current estimates because of the impact of a byproduct from the oil refining process, according to a new study being released this morning.

The report from Oil Change International, an anti-fossil fuel group, finds that the TransCanada pipeline's projected annual emissions are 13 percent above current projections from the U.S. State Department.

That is because current analyses are not accounting for the carbon dioxide that would be released from burning petroleum coke, a coal-like solid that is produced from refining heavy oil, like that found in Canada and Venezuela.

If fully built from Alberta to Texas, the Keystone XL pipeline would lead to the vproduction of enough carbon-rich petroleum coke to fuel five coal-fired power plants, the analysis says. In total, proven reserves in the Canadian oil sands could produce enough petcoke via the refinery process to fuel 111 U.S. coal plants through 2050, it states.

"Bitumen yields more petroleum coke than any other type of oil," said Lorne Stockman, research director at Oil Change International. "We are saying that these emissions cannot be forgotten with the Keystone XL pipeline."

Fifteen to 30 percent of a barrel of oil sands crude can be turned into petroleum coke, according to the report. That compares to 1 percent or so from many light oils, Stockman said.

Additionally, petroleum coke typically yields more carbon dioxide than coal, he said. Because coke is cheap, it could provide some incentive for some Midwestern power plants to stay economical for a longer period of time, according to the report.

"Petcoke produced in U.S. refineries and Canadian upgraders is increasingly being blended with coal in coal-fired power plants in the U.S. and abroad," the report says.

In anticipation of a greater supply of Canadian oil, refineries on the Gulf Coast invested heavily in equipment to produce petroleum coke over the past decade, Stockman said.

'Act of desperation'?

Petcoke production capacity in the United States grew from less than 90,000 daily tons in 1999 to more than 150,000 tons in 2011, the report states.

Sixty percent of U.S. petcoke is exported, with Asia a growing market. According to an Energy Department analysis, petcoke growth "was a major contributor to the United States becoming a net exporter of petroleum products in 2011 for the first time since 1949."

In the environmental impact statement for the original Keystone XL pipeline proposal in 2011, the State Department concluded that the higher CO2 emissions associated with Keystone XL in comparison to traditional oil essentially were irrelevant, since Canadian oil would be extracted regardless of the construction of the pipeline (ClimateWire, July 25, 2011).

Yesterday, supporters of the oil sands and Keystone XL said the petroleum coke analysis doesn't change that dynamic.

"This is an act of desperation by a group bent on halting all oil and natural gas production while destroying jobs and our economy. They have to keep changing their message and resorting to these kinds of stunts because they lack substance on this issue," said Cindy Schild, senior refinery manager at the American Petroleum Institute.

She said the industry "is not increasing volumes; we are offsetting the imports from places like Venezuela." Another analyst agreed, saying that "the emissions argument is silly, because the petroleum coke would just come from other heavy oils without Keystone XL."

Shawn Howard, a spokesman for TransCanada, added that research from two climate scientists last year published in Nature Climate Change found that emissions from the oil sands are small in comparison to those from coal (ClimateWire, Feb. 21, 2012).

Pressure on State Department

Stockman said he did not disagree that oil from Keystone XL could offset other heavy oils. The point, he said, is that the CO2 emission numbers associated with the TransCanada project and the Canadian oil sands are far too low.

Additionally, the building of pipelines like Keystone XL allows the Canadian industry to reach its long-term production goals, he said. Via new proposed pipelines to move crude out of Alberta, the industry is planning for a more than doubling of oil sands production by 2030.

The new pipelines -- if they are not blocked from opposition -- could then lead to much more petroleum coke production down the road via an investment signal, said Stockman. Without the pipelines, the industry could stall, he said.

The analysis is part of a continued environmental push for the State Department to include climate change in an upcoming draft environmental impact statement of the northern segment of the TransCanada project, which would run from Canada to Steele City, Neb., where it could connect to another oil line into the Gulf Coast.

Today, Stockman and representatives from the Natural Resources Defense Council, Canada's Pembina Institute and the University of Toronto will hold a press conference discussing the new research, including an additional paper finding that Canada's oil industry can't grow to its desired 2030 production levels without Keystone XL and several other large, proposed oil projects that are facing strong opposition.

The environmental research comes on top of a second letter sent from prominent climate scientists this week to President Obama, urging him to reject the pipeline because of its climate impact.