PUC approves Aqua Ventus wind-power contract

Courtesy / Maine Aqua Ventus The Public Utilities Commission yesterday approved a contract that allows Maine Aqua Ventus, an offshore wind energy demonstration project, to move forward. Here, a worker at Cianbro's Brewer facility checks on a prototype offshore wind platform.

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By Laurie Schreiber

The state Public Utilities Commission voted unanimously Tuesday to approve a 20-year contract under which Central Maine Power Co. will purchase electricity generated by Maine Aqua Ventus at an offshore wind energy site 2.5 miles south of Monhegan Island.

Aqua Ventus is a deep-water wind power research initiative by the University of Maine and partners including Cianbro Corp. Project plans call for up to two floating wind turbines to be located in the Gulf of Maine, according to a news release.

"The contract provides Maine Aqua Ventus the opportunity to demonstrate the commercial viability of the technology, while also providing Maine with a new clean renewable energy resource,” PUC Chairman Philip Bartlett said in the release.

The project also has the potential to provide significant benefits to Maine’s economy.

UMaine has estimated that Aqua Ventus will produce nearly $152 million in economic output and more than 1,150 Maine-based jobs, including ones in design and construction. Operations and maintenance are expected to create additional economic output of about $30 million over 20 years.

But the project stalled in 2018 when the three-member commission agreed to reconsider terms of the Aqua Ventus 2014 power purchase agreement with CMP.

In June 2019, Gov. Janet Mills signed into law LD 994, a measure sponsored by state Sen. David Woodsome directing the PUC to approve the contract.

Floating wind turbines

Aqua Ventus generates power with “VolturnUS 1:8”, a 65-foot-tall floating turbine prototype that is one-eighth the scale of a planned six-megawatt turbine with a 450-foot rotor diameter.

VolturnUS is the first grid-connected offshore wind turbine in the Americas, and incorporates 30 pending patents for its semi-submersible concrete hull technology. The turbine was designed and built at UMaine, assembled at Cianbro’s facility in Brewer, and launched in May 2013 with more than 2,000 people watching.

From Brewer, the turbine was towed nearly 30 miles by a Maine Maritime Academy tugboat, and was tested in Penobscot Bay, off of Castine, in 90 feet of water. In June 2013, VolturnUS delivered electricity through an undersea cable to the CMP grid.

Based on the success of the 1:8 scale pilot, the U.S. Department of Energy has awarded UMaine $40 million to construct a full-scale prototype.

When scaled, the VolturnUS technology may be capable of producing power at a “levelized cost” of less than $70 per megawatt-hour, according to Habib Dagher, principal investigator of the project and executive director of UMaine’s Advanced Structures and Composites Center.

Levelized energy cost refers to a measure of a power source that allows comparison of different methods of electricity generation on a consistent basis.

Dagher is optimistic about technology's potential. "Interest from offshore wind developers is very strong,” he told Mainebiz.

In October, the U.S. Department of Energy announced a $5 million award to UMaine to upscale the hull design using a larger 10-megawatt to 12-megawatt turbine.

“Once all permit approvals are in place, the goal is to start construction in 2021,” Dagher said.

Jeff Thaler, associate University of Maine counsel, noted there is still much work to be done, including many local, state and federal regulatory reviews of the environmental and related impacts of the project.

Reaction to PUC

In a prepared statement, Mills applauded the PUC’s approval of the contract and called Aqua Ventus “a first-of-its-kind floating offshore wind pilot project.”

“The PUC’s approval of this contract is a major milestone for our state’s clean energy future,” Mills said. “Thanks to the innovative work of the University of Maine, Aqua Ventus is poised to become the first offshore wind project in the country to feature a floating platform, an advancement that cements our state’s leadership in offshore wind development and that puts Maine on the map for clean energy technology.

"With this key and long-overdue approval, this cutting-edge demonstration project is now on track to move forward and allow us to harness our own clean, renewable source of energy, create jobs, and strengthen our economy.”

University of Maine President Joan Ferrini-Mundy said in an email to Mainebiz: “The approval today by the Maine Public Utilities Commission of a power contract for the Maine Aqua Ventus floating offshore wind demonstration project is an important step in our long effort to show how our patented floating platform technology will greatly benefit our environment and economy.

“As this sector changes rapidly, we remain committed to bringing to fruition a research-based, new, sustainable technology that can yield positive economic and environmental benefits for Maine and the country."