Keystone XL would not add to greenhouse gas emissions, according to a study published Thursday by an independent research group that echoed the findings of government-backed reports.

The study found that the addition of the new pipeline connecting Canadian oil sands fields with the U.S. Gulf Coast wouldn’t make a substantial difference in emissions because U.S. refineries would get similar crude from Venezuela or elsewhere.

Production, processing and transportation of Venezuelan heavy crude results in about the same greenhouse gas emissions as oil sands crude, according to the study from energy-focused information and research firm IHS CERA.

A prior report from IHS CERA said that Keystone XL would offer an alternative to Venezuelan and Mexican crudes.

Environmentalists have argued that Keystone XL would add to greenhouse gas emissions and therefore fail a key test for the pipeline set by President Obama.

Pipeline opponents also argue that if Keystone XL were not completed there would less interest in producing crude from Canadian oil sands, resulting in an overall environmental benefit. An analysis from investment bank Goldman Sachs supports that argument, said Anthony Swift, an attorney for the Natural Resources Defense Council.

The Goldman Sachs analysis estimated that there will be 230,000 barrels per day of excess Canadian oil sands crude production next year, since that production won’t be able to reach markets. The Keystone XL pipeline, if it is approved, could be completed in 2015, unloading some of that surplus, the Goldman Sachs analysis said. But in the absence of that pipeline and other options, the price of Canadian oil sand crude could fall dramatically, to as low as $50 per barrel – less than half of today’s U.S. benchmark oil price – possibly resulting in lower production, the Goldman Sachs analysis said.

“The reality is, the tar sands industry’s expansion plans are facing both short- and long-term constraints,” Swift said.

But the IHS CERA report said that even without the pipeline, production of oil sands crude in Canada would continue and would find other ways to markets.

“Given sufficient investment, our view is that the economics for moving heavy oil sands crude by rail could improve further, even approaching pipeline economics,” the report said. “Consequently, even without the Keystone XL pipeline, we believe that oil sands production would grow at a similar rate. Therefore (greenhouse gas) emissions will be unaffected by the fate of Keystone XL.”

Despite arguments from environmentalists to the contrary, IHS CERA found that rail transportation of oil sands crude is likely to be a cost-effective option for producers. The Goldman Sachs report also questioned the feasibility of moving Canadian oil sands crude, which could be complicated. But Goldman Sachs also predicted a rise in rail movements to move any oil out of Canada that couldn’t be shipped on pipelines.

Oil sands crude is made up mostly of bitumen, a solid, hydrocarbon-bearing material. To move it in pipelines, producers have to heat and dilute the bitumen, creating a substance called diluted bitumen. Diluted bitumen, or dilbit, is made up of 70 percent bitumen and 30 percent diluents, according to IHS CERA.

But oil producers and refiners could move pure bitumen by rail instead, making it more cost-effective, IHS CERA said.

“By railing pure bitumen (instead of dilbit in a pipeline or rail car) oil sands producers can avoid some expense—specifically cost for the diluent—plus there would be fewer barrels to transport (compared with dilbit, shipping pure bitumen decreases the total volume moved by 30%),” the report said. “These savings offset some of the extra costs associated with rail transport.”

If oil shippers were to take this route, they could make rail movements of bitumen just $6 more expensive than pipeline movements, making it worthwhile, IHS CERA said.

Movements of pure bitumen by rail would require new infrastructure, which companies have not pursued because they have expected pipelines like Keystone XL to meet their shipping needs, the study said.

“However, if producers anticipate that new pipeline capacity will not keep pace with oil sands growth, we expect that they will make investments in more efficient rail transport, including equipment for moving pure bitumen,” the study said. “These investments would narrow the gap between the economics of transporting oil sands by pipeline and by rail.”