The Minnesota Public Utilities Commission unanimously approved plans Wednesday by Enbridge Energy to boost the capacity of its Alberta Clipper oil pipeline in Minnesota as environmental and Native American protesters chanted in opposition.

The Enbridge project, like TransCanada's proposed Keystone XL pipeline in western states, has drawn protesters who oppose transporting more crude oil from the tar sands region of Alberta to the United States.

But the Minnesota Commerce Department, which reviews energy projects, supported the upgrade, saying it would ensure "a continued, reliable cost-effective supply of crude oil to Minnesota and the region from a consistent and stable supply region." The department projected that a likely alternative if the pipeline isn't built — shipping crude by railroad — would require 7,000 tank cars traveling through the state.

"There is no need for this pipeline," John Munter, who lives with his family in Warba, Minn., about 4 miles from the Enbridge line, said as he stood outside the PUC's offices with a sign that said, "No Tar Sands Genocide."

Munter was the first anti-pipeline protester to show up for the St. Paul meeting, but was later joined by about 50 others, many of whom wanted to speak to the PUC, which didn't allow testimony. The protesters included activists from MN350.org, a climate-change advocacy group, and Honor the Earth, led by Winona LaDuke of the White Earth Reservation in Minnesota. (In 1996 and 2000, LaDuke was the Green Party's vice presidential candidate on the ticket headed by Ralph Nader.)

Commissioners, after a brief discussion that was repeatedly interrupted by protesters, voted that the project is needed, citing its favorable economics. Regulators declined to take additional testimony — having sponsored two public hearings earlier this year — and did not address environmental concerns.

Separately, the U.S. State Department is conducting an environmental review of the Enbridge expansion plan because the project also requires a Presidential permit to expand oil shipments across the border. The proposed Keystone XL pipeline, which also requires a Presidential permit, has attracted significant opposition from environmental groups.

The Minnesota project is part a broad plan by Enbridge to upgrade pipelines in the United States and Canada to ship more Canadian oil to the Midwest and beyond. The Canadian Association of Petroleum Producers last month projected that Canadian oil output will more than double by 2030 to 6.7 million barrels per day, with most of the increase from the Alberta oil sands.

Enbridge intends to spend $40 million to upgrade three Minnesota pumping stations, at Viking, Clearbrook and Deer River, allowing them to push 27 percent more oil through the 36-inch Alberta Clipper pipeline, which runs 1,000 miles from Hardisty, Alberta, to Superior, Wis.

When it constructed the line four years ago, Enbridge says, the pipe was oversized with the intention of possibly increasing throughput later. With the upgrade, the line could carry 570,000 barrels per day. Enbridge officials said they hope to begin construction of the larger pumps next month.

Climate-change activists have been campaigning against Canada-to-U.S. pipelines, hoping that stopping them will slow or halt production in northern Alberta. The Natural Resources Defense Council says producing oil from tar sands releases three times more greenhouse gases than conventional oil production. The oil industry disputes those claims.

Protesters in St. Paul were disappointed by the PUC outcome, though not particularly surprised.

"Our goal is to keep tar sands crude in the ground," said Tom McSteen of MN350.org, which helped organize the protest and now plans to press the environmental case with the State Department.

David Shaffer • 612-673-7090 • @ShafferStrib