An estimated $447 million in power transmission reliability investments are on the horizon through 2028, according to the latest update of ISO New England’s Regional System Plan Project List, ISO-NE said on July 7.
Two new projects were added, and no upgrades were placed into service in the last few months, according to the ISO’s June 2025 update.
There are 20 active projects as of this update, including:
• Six projects under construction
• 12 planned projects
• Two proposed projects
Most of the active projects are in Massachusetts (11) and Maine (six). There is one active project in New Hampshire, one in Rhode Island, and one in Connecticut. There are no active projects in Vermont.
Since 2002, the ISO’s work in power system planning—one of its three critical roles—has facilitated $13 billion in transmission investment, with a total of 879 project components placed into service.
In addition to their primary goal of bolstering reliability, "some of the projects have decreased transmission system congestion and prepared the grid for a cleaner future," the grid operator said.
About the Project List
Published three times a year (in March, June, and October), the Regional System Plan Project List describes the status of pool transmission facility projects needed to ensure reliability in New England.
As a part of the regional system planning process, the ISO must continually:
• Reassess the timing and components of existing projects to accommodate forecasted changes in net loads, the retirement of generating resources, and the addition or delay of new power resources
• Study the ability of the New England transmission system to meet federally mandated reliability requirements and adequately serve the region.
The ISO’s role in system planning includes seeking input from its Planning Advisory Committee. The committee’s open, public meetings provide a forum for stakeholders -- including generator owners, transmission owners, government and community representatives, and others -- to offer feedback on the regional system planning process.
