The Minnesota Public Utilities Commission (PUC) has given the green light to plans by Canadian oil company Enbridge Energy to expand the capacity of its Alberta Clipper pipeline running through the state, amid opposition from environmental and Native American organizations, Energy Global reported.

Calgary-based Enbridge submitted plans for boosting the capacity of the pipeline in an effort to ensure the transportation of more crude oil from Alberta's tar sands to the United States. Critics of the expansion have been opposing the project for months, fearing that an increase in pipeline capacity would accelerate the development of Alberta's oilsands. The production of oil from oilsands is estimated to produce three times more greenhouse gases than conventional oil production. Environmentalists had been hoping that demonstrations would slow down or even stop the production and import into the United States.

However, the Minnesota Commerce Department, responsible for evaluations of the state's energy projects, approved the plans for the expansion, pointing out that it would be beneficial for the economy and would result in a "reliable cost-effective supply" of crude oil to the U.S. Midwest and beyond. The most likely alternative — moving crude by train — would lead to 7,000 tank cars traveling through the state, which would go against the state's carbon emission reduction plans.

Enbridge's project for increasing the Alberta Clipper pipeline capacity at the Minnesota section is part of a large-scale plan by the company to upgrade its pipelines across the United States and in Canada. The company announced it planned to invest about $40 million to overhaul three major pumping stations in Minnesota — Viking, Clearbrook and Deer River. Upgrading them would allow up to 27 percent more oil to flow through the 1,000-mile Alberta Clipper pipeline. After the capacity boost, the the pipeline will be able to transport up to 570,000 barrels per day. According to Enbridge officials, construction work on the three pumps could begin as early as next month.

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Meanwhile, the U.S. State Department is carrying out an environmental review of the broader Enbridge expansion plan because the project also requires a permit from the Obama administration to increase oil shipments from Canada into the United States.

While the Minnesota PUC was debating Enbridge's proposed upgrade, a group of about 50 protesters tried to interrupt the discussion several times, asking to give testimony. State lawmakers refused to hear any of the protesters, explaining that earlier in the year two separate public hearings on the matter had taken place. Commissioners unanimously voted in favor of the expansion, citing the economic benefits of the project as a motive for their ruling, Energy Global said.

According to an analysis carried out by the Canadian Association of Petroleum Producers in June, Canadian oil output is projected to more than double to 6.7 million barrels per day in 2030, with Alberta oilsands accounting for a large proportion of this increase.