BANGOR, Maine — A Penobscot County jury last week awarded Eastern Maine Electric Cooperative more $13.6 million in lost profits in a breach of contract lawsuit against First Wind Holdings and four of its subsidiaries.

Sigmund Schutz, the Portland attorney who represented the cooperative, called the damage award “among the largest jury verdicts ever awarded in Maine.”

The cooperative is a consumer-owned electric utility headquartered in Calais. It serves about 12,500 customers in portions of Aroostook, Penobscot and Washington counties.

“The defendants’ breach denied the cooperative of the benefits of the deal, and forced the cooperative to take legal action,” Scott Hallowell, the cooperative’s chief executive officer, said Monday in a press release. “We are extremely pleased with the verdict, as it vindicates the cooperative’s position that the wind companies did not negotiate in good faith.”

Efforts to reach attorneys for First Wind to determine if an appeal might be filed were unsuccessful Tuesday.

The 2011 contract required the wind power companies to act in good faith to finalize the sale to the cooperative of a 12.54-mile section of transmission line connecting two wind farms located on Stetson Mountain in northern Washington County and another on Rollins Mountain near Lincoln in Penobscot County to the electric power grid, according to a press release issued Monday by the cooperative.

The parties had agreed that the three wind farms would pay for costs, including repairs and upgrades to the line, which is standard in the industry, the release said. The final contract was never signed.

The cooperative in October 2014 sued First Wind and its subsidiaries in Penobscot County Superior Court. The following month, First Wind moved the case to U.S. District Court in Bangor.

In May 2015, a federal judge sent the case back to state court after denying a motion to dismiss it. The case then was assigned to the Business and Consumer Court, which is based in Portland but holds proceedings in courthouses throughout the state.

Evidence was presented to a jury of nine Penobscot County residents over four days last week, according to the court clerk’s office. Jurors deliberated for about two hours Friday before unanimously ruling in the cooperative’s favor.

In addition to the $13.6 million the cooperative demanded in its lawsuit, the jury awarded it legal fees and costs along with pre- and post-judgement interest, which will be determined at a later date by Superior Court Justice Michaela Murphy, who presided over the trial.