HALLOWELL — Less than two weeks ago, a Canadian energy company and a major wind power developer with turbines in Maine announced they had closed a deal worth hundreds of millions of dollars to expand wind power projects across the Northeast.

The announcement left out an important fact that could jeopardize the deal: legal appeals were filed just days before by the state’s Office of the Public Advocate and a Maine utility company. The appeals challenge a ruling by a state agency that cleared the way for the joint venture.

“I was somewhat surprised (to see the announcement that the deal had closed),” said Eric Bryant, the attorney in the public advocate’s office, who filed one of the appeals. “It’s unusual for a company to make a decision when there’s risk involved that it may have to undo it because of a legal matter.”

The partnership is between Emera, a Canadian energy company that owns electric utilities in the Northeastern U.S., Atlantic Canada and elsewhere, and First Wind, which develops, operates and owns utility-scale wind projects across the U.S. First Wind is the Northeast’s largest wind power developer and has four major wind projects in Maine, with a fifth, Bull Hill, under construction.

“The completion of the joint venture could lead to up to $3 billion in future economic investment in the region in the coming years,” the companies’ June 15 announcement said.

The deal means that First Wind, which failed to go public in 2010, will receive the money needed to build more wind turbines from Emera. Maine currently has 205 commercial wind turbines that can produce 400 megawatts of electricity. The Emera-First Wind venture could pave the way for construction of turbines producing an additional 1,200 megawatts.

The appeals by the public advocate and Houlton Water Co. argue that the state Public Utilities Commission should not have allowed Emera and First Wind to go ahead with the joint venture.

Those appeals were joined by a third, similar appeal filed June 20 by the Industrial Energy Consumers’ Group, which represents large energy users and advocates for lower electricity prices.

The PUC approved the joint venture in April, which cleared the way for the two companies to complete the process that led to the June 15 announcement.

The applicants to the PUC were actually Bangor Hydro and Maine Public Service, the regulated utilities in Maine that are owned by Emera. Commissioners gave their approval despite the PUC staff’s recommendation to reject the deal on grounds it posed a risk of higher prices to ratepayers.

The appellants in the case said that the proposal would violate the state’s landmark electricity restructuring act, which barred transmission companies like Bangor Hydro from owning electricity generation. The law prohibits utilities from owning both transmission and generation because it is seen as anti-competitive and contributes to high electricity prices.

“The commission committed an error of law, abused its discretion and failed to follow the mandate of the Legislature … in concluding that the ownership of generation assets in Maine by an affiliate of a transmission and distribution utility is not prohibited by the electric industry restructuring statutes,” Bryant wrote in his notice of appeal.

The appeals go further, claiming the PUC acted outside of its legal authority when commissioners imposed a long list of conditions on Emera and First Wind designed to mitigate any potential harms from the deal.

The problem with imposing those conditions was that technically, Emera, First Wind and Canadian company Algonquin Power & Utilities Corp. aren’t regulated by the PUC. As a result, the companies filed letters with the PUC saying they would submit to the commission’s jurisdiction.

First Wind’s letter says it “accepts the Commission’s authority to enforce the Order … including the Commission’s authority to enforce all conditions in the order applicable to First Wind, as if First Wind were a party to this proceeding.”

Appealing parties say the decision to extend the commission’s statutory authority cannot be made by simply saying so.

“The commission has, in order to make this deal reasonable, set forth a slew of conditions that apply to First Wind, Algonquin and Emera,” said Alan Stone, attorney for Houlton Water. “We argued you can’t do that because you don’t regulate those entities and they’re not parties to the case.”

Stone says that without the legal authority to impose and enforce the conditions, the conditions can be challenged at any time.

“The commission said, ‘Just sign a letter that you agree to them,’ and our position is that it’s not enough, you can’t invest the commission with powers it doesn’t have simply by signing an agreement,” he said.

A PUC spokeswoman, Pauline Collins, said “We don’t have any comment on the merits of the appeals. What we have to say will be in our brief (to the court).”

Both First Wind and Emera spokespeople declined to comment on the appeals.

The Maine Supreme Court is likely to consider the case in the fall, after the appellants file their briefs in August and the PUC files its response in late September.

Naomi Schalit and John Christie are senior reporters for the Maine Center for Public Interest Reporting, a nonpartisan, nonprofit news service based in Hallowell. E-mail them at mainecenter@gmail.com or visit the website at pinetreewatchdog.org.