The Monhegan test site was selected through a state-run process that included locations off uninhabited Boon Island and Damariscove Island. Monhegan was picked because it’s 12 miles from the mainland, has steady winds, a limited number of fishermen and extreme electric rates. The site selection was challenged in court by a conservation activist, but was upheld in 2011.

The 2009 law that designated the site allowed up to two turbines, a maximum capacity of 25 megawatts and one transmission cable to the mainland. In early meetings with island officials, though, the university promoted a one-third scale turbine, with no cable, and a test period of months. But over time, the scope of the project changed. Engineers decided to test a one-eighth scale model of the floating concrete platform off Castine, in more-protected waters. Maine Aqua Ventus also won a Department of Energy award for commercial-scale testing.

That led to an upgraded design for two 6-megawatt turbines on full-size platforms off Monhegan, with a cable to the mainland and the island. The test period grew to 20 years.

The opposition group Protect Monhegan formed last fall after it became clear that the full-scale project might become a reality. The group raised $40,000, some of it from visitors and summer residents, and hired legal and public relations help. That led to the bill aimed at relocating the project, heard by a legislative committee Tuesday.

By Tux Turkel, staff writer