Dive Brief:

Eight different developers have proposed 36 transmission upgrades designed to help ISO New England address reliability issues created by the two-stage closure of Exelon's Mystic Generating Station in the early 2020s .

. The grid operator issued a request for proposals in December 2019, marking the ISO's first competitive transmission solicitation under the Federal Energy Regulatory Commission's Order 1000 framework. The process aims to yield more creative solutions to transmission needs that are not considered time-sensitive.

While the ISO is not releasing specific information about the projects, some developers have commented publicly. National Grid and Eversource submitted eight proposals including upgrades to existing properties. Developer Anbaric proposed the Mystic Reliability Wind Link, an underwater and underground transmission link into Boston that the company says would utilize existing infrastructure.

Dive Insight:

The New England grid operator will review dozens of transmission upgrade proposals in a two-stage process, with a final selection expected to be made next year.

An initial assessment of the projects will "screen out those proposals that do not solve the identified needs, are not feasible, or are not competitive with the other proposals," ISO spokesman Matthew Kakley said in an email. Those that meet the requirements "will progress to the second step of the process, in which developers must provide much more detailed information."

The ISO expects to make a final selection in the summer of 2021, Kakley said.

Among the projects is ​Anbaric's wind link, which officials say can be completed by 2024 to avoid the risk of continuing annual payments of $200 million to $300 million to keep the Mystic Generating Station operating.

Heading into ISO New England's 13th Forward Capacity Auction last year, Exelon announced plans to retire the Mystic plant Station in June 2022. While the ISO retained two of the Mystic units under rules that permit retentions for fuel-security reasons, they are scheduled to retire in 2024.

Mystic is a 2,000 MW gas- and oil-fueled power plant supplied by liquefied natural gas from the Everett facility which Exelon also owns. ISO New England concluded its closure could cause overloaded transmission lines and overall system instability.

Anbaric officials say their project aims to bring planned offshore wind power from Southeast Massachusetts directly to Boston, and avoids the need to upgrade existing onshore power lines through disruptive construction.

"Seeing Boston and how hard it is to get through the streets, we designed a project that utilizes the substation used to by Pilgrim and runs up to the Mystic substation," Theodore Paradise, Anbaric's senior vice president of transmission strategy, told Utility Dive.

Entergy last year shut down its 680 MW Pilgrim Nuclear Power Station in Plymouth, Massachusetts. Anbaric officials say their project would reduce Boston's reliance on fossil fuel plants that have covered the lost generation from Pilgrim while using infrastructure already in place to deliver energy.

"We've done a lot of routing work early, so we're not just saying we could do it," said Paradise.

Also on the table will be eight proposals from National Grid and Eversource, which the companies say have the "added benefit of enabling cost-effective delivery of clean energy resources like offshore wind." One of the projects will be capable of supporting an additional 1,100 MW of clean energy during peak demand hours.

"We have a high degree of confidence that our innovative solutions can be delivered on time and will provide significant environmental and financial benefits to customers throughout the region," Eversource President of Transmission Bill Quinlan said in a statement.

The eight proposals submitted by Eversource and National Grid range in cost from $48 million to $120 million, the companies said. They claim the most cost-effective solution maximizes the use of existing transmission facilities in the Boston area, keeps upgrades "entirely on properties already in use by the energy companies," and will be in-service eight months prior to the planned retirement of Mystic.

Eversource and National Grid say all of their proposed solutions come in with costs "well below" an estimated $175 million annually, excluding fuel costs and capacity credits, that New England consumers will pay to keep the Mystic Station available.

With support also needed for the Everett LNG facility to supply Mystic, Anbaric's Paradise said the total cost is closer to $300 million annually to keep the plant operating. The company's proposed wind link "not only solves reliability problems," he said, "but also creates significant new import capabilities."