State hears competing offshore wind proposals 

The developer of the nation’s first offshore wind farm proposed to the state on Wednesday a multi-phase wind project in conjunction with the owner of Northfield Mountain Pumped Storage Project and National Grid.

Responding to a call by the Massachusetts Department of Energy Resources for companies to supply at least 400 megawatts of offshore wind power to Massachusetts’ utilities, Deepwater Wind, which built five turbines off a year ago, submitted a proposal Wednesday to build a scalable project that would be partnered with an offshore transmission backbone touted as the “first of its kind” through partnerships that would make it “capable of delivering clean energy when it’s needed most, during peak hours of demand.”

Providence-based Deepwater Wind is vying with Bay State Wind and Vineyard Wind for lucrative contracts, as the state is requiring electricity distribution companies Eversource, National Grid and Unitil to purchase 1,600 megawatts of power from offshore wind by 2027, roughly enough to power up to 1 million homes. A decision by the state is expected next year.

Deepwater’s Revolution Wind proposal would be pared with a transmission backbone developed in partnership with National Grid.

Also part of the package, Revolution Wind would partner with FirstLight Power, whose Northfield Mountain hydroelectric project stores energy in the form of water that’s pumped to a mountaintop reservoir for release through underground turbines when there is peak demand for generation.

“We are proposing a next generation renewable energy project. It’s the first of its kind in the world, and that’s why we call it Revolution Wind,” said Deepwater Wind CEO Jeffrey Grybowski, explaining that the company’s two submitted proposals call for about 25 turbines generating 200 megawatts of power as well as a 50-turbine operation generating 400 megawatts. “Our offshore wind solution can replace power plants of prior generations that are now retiring. Offshore wind produces a massive amount of clean energy and we can now deliver that power even when the wind is not blowing,” through contracts with FirstLight.

“Plus, building an offshore transmission backbone that multiple offshore wind projects can connect to over the coming years means we’re building a smart system that won’t duplicate costs from multiple projects.”

Deepwater’s Massachusetts vice president, Matthew Morrissey, explained that Deepwater’s contract with FirstLight provides for a share of the proposed off-peak wind generation to help “conceptually power those pumps” at Northfield Mountain, which stores that energy for later, when it’s most needed.

“We’re very excited to collaborate with Deepwater Wind and National Grid to help Massachusetts reduce greenhouse gas emissions and reach its environmental goals,” said John Shue, FirstLight Power Resources’ senior executive. “Pairing clean energy storage at Northfield Mountain with offshore wind energy will ensure that the people of Massachusetts capture the greatest environmental benefit they can, in the most efficient manner possible.”

The wind-farm project, includes “overbuilding a large enough substation foundation platform to accommodate substations from future projects and then permitting one corridor that would accommodate multiple lines from future projects,” Morrissey said.

Deepwater Wind plans to build its new submarine transmission connection between Revolution Wind to a Brayton Point substation in Somerset, giving National Grid the right to purchase the completed transmission connection from Deepwater and operate the 1,600 megawatt corridor for future projects to avoid having to build additional substations.

“We’re not building one giant 1,600 megawatt line right now,” Morrissey said. “We’re building the ability to easily connect with this larger substation, and future projects would run their own line in a corridor that’s already permitted.”

Deepwater Wind, which is vying with Vineyard Wind and Bay State Wind, is proposing wind farms for federal waters about 30 miles from the mainland and about 15 miles from Martha’s Vineyard. All three firms have secured federal water development rights off Martha’s Vineyard.

(This article incorporates Associated Press reporting.)