Turbines in the Bull Hill Wind project in Township 16 in Hancock County rotate in the breeze in this May 2018 file photo. Developers for the proposed Weaver Wind project a few miles away are offering to conserve 5,800 acres of land in eastern coastal Maine to mitigate the impact that 22-turbine project is expected to have on birds. Credit: Bill Trotter

The state has approved a $147.5 million industrial wind-to-energy facility proposed for Hancock County after a four-year delay caused by concerns about the project’s impact on area bats and birds.

The Maine Department of Environmental Protection announced its awarding of a site permit to Longroad Energy’s 22-turbine Weaver Wind project in Eastbrook and Osborn on Friday. Opponents have 30 days to appeal to the Maine Board of Environmental Protection, spokesman Mark Bergeron said.

Attempts to contact Longroad were not immediately successful on Friday.

First proposed in December 2014 by developers First Wind and then by SunEdison, which withdrew its DEP application in 2015, the project survived opposition from the Department of Inland Fisheries and Wildlife over concerns that it would kill birds and bats and disrupt nesting grounds.

But state officials “and the applicant have worked closely in consultation with us to work out those issues,” Bergeron said Friday.

Each of the 22 turbines would be nearly 600 feet tall from ground to the highest tip of each blade, and would be rated for 3.3 megawatts of generating capacity for a total power capacity of nearly 73 megawatts. Fourteen would be in Osborn and eight would be in Eastbrook, Longroad has said.

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To allay state concerns, Longroad agreed to set aside 5,791 acres for bird habitation in Hancock north of the Downeast Sunrise Trail and in Whiting near Holmes Bay. Longhorn will work with naturalists to create a land management plan to help the birds and bats survive, according to the permit approval.

To help protect bats, Longhorn will curtail turbine operations nightly from April 15 to Sept. 30 for at least 30 minutes before sunset and after sunrise when ambient temperatures are above 32 degrees Fahrenheit, depending on certain wind conditions. Turbines will only operate at wind speeds exceeding 6.0 meters per second from April 15 to July 15 and Sept. 16-30 and at speeds exceeding 6.5 meters per second from July 16 to Sept. 15. Turbines will be feathered during the curtailment and turn at no more than one revolution per minute to minimize risks of bat mortality, the approval states.

As part of the project, Longroad will build an operations center near Route 9 in Aurora and would connect to the grid at an Emera substation near the 34.5 megawatt Bull Hill wind farm in Township 16, which was developed by First Wind but now is owned and operated by TerraForm Power.

Longroad would likely wait until the appeal period lapses before beginning construction, Bergeron said.

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