PORTLAND, Maine — Ending a partnership challenged twice before state regulators and in court, Nova Scotia-based Emera has sold its interest in a $333 million joint venture with First Wind, which was purchased Monday by a Missouri-based renewable power developer.

Emera announced Monday that it has agreed to sell its interest in Northeast Wind Partners back to First Wind for $223 million.

The deal would end a legal challenge to that partnership, which Houlton Water Co. and a group representing industrial power users argued violated the intent of New England’s deregulation of its electricity market. But that money may be directed at other power generation resources in the region after the completion of the larger deal between First Wind and SunEdison subsidiary TerraForm Power.

That deal, announced Monday, is expected to close early next year.

“This transaction is essentially an unwinding of our original transaction with First Wind as they pursue a new direction and we seek to redeploy our capital in higher value assets and opportunities in other clean energy infrastructure investments, including electricity transmission and natural gas electricity generation in the Northeast,” said Chris Huskilson, Emera’s president, in a news release Monday.

Paul Gaynor, CEO of First Wind, said the partnership had been “fruitful” but said the split was a “positive move for all of the parties involved.”

Opponents of the partnership had won in a ruling earlier this year before the Maine Supreme Judicial Court, which found that state regulators did not properly determine whether the relationship between Emera and First Wind provides an incentive for the subsidiary of the utility, Emera Maine, to favor one power generator over another.

Regulators reviewed that decision a second time and approved it in a 2-1 vote in July, with Commissioner Mark Vannoy as the lone dissenting vote on the Maine Public Utilities Commission.

The uncertainty of the deal had brought additional scrutiny from the state’s Department of Environmental Protection, which questioned First Wind’s ability to finance decommissioning of its wind power projects without investment from Emera.

The deal announced Monday gives massive financial backing to First Wind, which has a backlog of about 1.6 gigawatts of wind development, including 384 megawatts across sites under construction in Oakfield, near Ellsworth and at a contested site in Bingham. The company has another 357 megawatts in the works from four other projects in development in Maine — by the project titles Weaver Wind, Bowers Wind, Molunkus Wind and Somerset Wind. The company has listed the Bowers project as still in development, despite denial of permits by the Department of Environmental Protection and on appeal by the Board of Environmental Protection.

The company appealed those denials to the Maine Supreme Judicial Court in July and a decision is still pending.

First Wind has five wind farms in operation in the state at sites in Mars Hill, two sites on Stetson Mountain, Rollins Wind near Lincoln and Bull Hill Wind near Eastbrook in Township 16.

Darren Fishell

Darren is a Portland-based reporter for the Bangor Daily News writing about the Maine economy and business. He's interested in putting economic data in context and finding the stories behind the numbers.