The Supreme Judicial Court delivered the coup de grace to Cape Wind opponents in their efforts to halt permitting of the controversial Nantucket Wind farm project. In a 4-2 decision, the majority ruled Tuesday that the state Energy Facilities Siting Board acted appropriately in approving Cape Wind Associates’ 2005 petition to build and operate two electric transmission lines to connect the proposed wind farm to the regional onshore power grid.

Unlike the wind farm itself, which would sit in federal waters and requires federal approvals, the transmission lines traverse about six miles of Lewis Bay and Nantucket Sound and require additional local and state approvals. The Cape Cod Commission, the town of Barnstable, and the Alliance to Protect Nantucket Sound petitioned the high court to reverse the state siting board decision, as well as invalidate a related Department of Environmental Protection regulation.

With the validation of the siting board permit, the project has now secured all necessary state and local permitting approvals. The justices’ ruling effectively ends further permitting challenges under Massachusetts law.

“I am gratified that the Court has upheld the state’s actions and regulations with regard to Cape Wind and brought to an end numerous legal challenges,” Secretary of Energy and Environmental Affairs Ian Bowles said in a statement. “With the high court’s approval, this important renewable energy project is free to go forward.”

However, Chief Justice Margaret Marshall and Justice Francis Spina concurred with parts of the decision, they also voiced this dissent:

The siting board, however, does not have, and was not intended by the Legslature to have, the right to act as fiduciary on behalf of the people with regard to Commonwealth tidelines or to approve energy projects up and down the coastline of Massachusetts in Commonwealth tidelands.

It may be that the Legislature or the Legislature’s expressly authorized designee…would conclude that transmission cables stretching across Commonwealth tidelines from the shore to the Commonwealth’s seaward boundary should be approved. But that authorization has not occured.

The court’s rulling to the contrary establishes a danagerous and unwise precedent, which has far-reaching consequnces. A wind farm today may be a drilling rig or a nuclear power plant tomorrow.

Those objections encouraged Cape Wind opponents like Audra Parker, president of the Alliance to Protect Nantucket Sound. She called the majority ruling an “outrageous violation of community rights for cities and towns throughout Massachusetts” on energy facility siting decisions.

Yet Parker didn’t see the SJC decision as a “green light for Cape Wind.” Even though the court decision closes the door on state and local permitting challenges, she viewed the controversy over the projected price of the electricity generated by Cape Wind as a major obstacle to the project.

“Over the last few months, there’s been a huge change in people’s understanding that wind is not free,” Parker told me. “[Cape Wind] excessively burdens businesses and households throughout Massachusetts.” Parker would like to see the state Department of Public Utilities deny the wind farm project because “it doesn’t make any sense to spend billions when other green energy sources are available at fraction of the cost.”

Cape Wind still has more challenges to face in the federal courts. There are federal permits pending action, with four different lawsuits by 10 different parties pending on those permits.

Clarification:  The four different lawsuits by 10 different parties are pending against several federal agencies, including the Department of the Interior and the Federal Aviation Administration. Federal permits have yet to be issued.

If and when federal permits are issued, unless a federal judge issues an injunction, Cape Wind can move forward with construction at its own risk. However, should any opponents prevail in a federal lawsuit, Cape Wind could be forced to stop construction or have its permits invalidated.

Gabrielle covers several beats, including mass transit, municipal government, child welfare, and energy and the environment. Her recent articles have explored municipal hiring practices in Pittsfield,...