Oil sands emissions 6 pct above other oil -study

* IHS CERA figure lower than that of environmental groups

* Emissions would need to be be halved to meet standards

CALGARY, Alberta, Sept 21 (Reuters) - Emissions from Canada’s oil sands, from crude production to end use, are 6 percent higher than from other oil imported into the United States, a study said on Tuesday.

While that is well below the levels cited by some environmental groups, meeting new rules on carbon emissions would still mean an unlikely halving of greenhouse gases from oil sands crude over the next 10 years, according to the study by energy think tank IHS CERA.

Those hefty emission cuts, borne by oil sands producers as more North American governments adopt tougher environmental standards, would be impractical without other carbon offsets, the study said.

California and other jurisdictions have set fuel policies calling for a 10 percent drop in life-cycle greenhouse gas emissions within a decade. Canada’s oil industry is concerned about the impact on costs and access to markets as more governments follow suit with low-carbon standards.

“It will be difficult to meet those,” said IHS CERA director Jackie Forrest, an author of the report, called “Oil Sands, Greenhouse Gases, and U.S. Oil Supply: Getting the Numbers Right.”

IHS CERA got its life-cycle average from the results of 13 government, academic and industry studies that put oil sands emissions at 5 percent to 15 percent above other crudes.

From production through to use in vehicles, the suppliers control 20 percent to 30 percent of emissions, so they would have to cut what they emit from extraction, processing and distribution by a third to a half to meet the overall 10 percent drop, the study said.

As an offset, capacity to provide and use alternative low-carbon energy sources, such as ethanol and electricity, would have to double from current levels, it said.

“On the supply side there are going to be issues as well as the consumption side,” Forrest said.

Canada’s oil sands are the largest crude reserves outside the Middle East, but have been tagged as a high-carbon fuel source due to the extra energy needed to mine the heavy crude or pump steam into the earth to allow it to be pumped to the surface.

Canada is already the top foreign supplier of oil to the United States. The industry and Alberta government have mounted an intense lobbying campaign in Washington to sell the benefits of the oil sands as a secure source and to show that companies are working to improve their environmental performance.

Numerous environmental groups seek to counter that, saying the oil sands are Canada’s fastest-growing source of carbon emissions due to the rapid expansion of the industry.

Indeed, groups including the Pembina Institute and the Toxics Watch Society of Alberta asked regulators on Tuesday to adjourn a hearing into Total SA's TOTF.PA Joslyn North oil sands mine, saying the company did not adequately assess its environmental impact when added to other companies' plans in the region.

IHS CERA said not all oil sands shipped to the United States has the same carbon emissions. As much as 55 percent is bitumen mixed with lower-emission lighter hydrocarbons. The remainder is light synthetic crude, which was processed within Alberta at plants that emit greenhouse gases.

One environmental group criticized the report, saying its own studies, examining many of the same sources, showed life-cycle emissions to be 8 percent to 37 percent higher than other crudes processed in the United States.

The National Resources Defense Council said it took issue with the calculation from diluting bitumen with light diluent and said IHS CERA left out some life-cycle impacts, such as land use and energy inputs to oil sands facilities. (Editing by Rob Wilson)