ISO New England is providing this web guide to assist you in understanding the interconnection process for small and large generating facilities and elective transmission upgrades (ETUs) to interconnect to the administered transmission system. However, you shouldn’t rely solely on this web guide. Consult the ISO New England Inc. Transmission, Markets, and Services Tariff (ISO Tariff), Section II, known as the ISO’s Open Access Transmission Tariff (OATT), and relevant planning procedures and operating procedures to ensure that you are complying with all requirements. In case of any discrepancy with this web guide, the ISO Tariff and applicable operating procedures and planning procedures govern.
As a Regional Transmission Organization (RTO), the ISO coordinates how transmission lines, power plants, and other resources connect to and operate on New England’s administered transmission system to ensure reliability and facilitate wholesale electricity market participation. The ISO does not administer the interconnection process for projects subject to state interconnection processes. Thus, after you determine that the ISO interconnection process applies to your project, you’ll need to submit an interconnection request to the ISO through the Interconnection Request Tracking Tool (IRTT). Existing customers can register for an account using IRTT, while new customers must first or simultaneously obtain an ISO customer ID and access to critical energy infrastructure information.
As required by the Federal Energy Regulatory Commission’s Order No. 2023, it is only possible to submit interconnection requests during a cluster request window. The next window to submit a complete interconnection request package for the next Cluster Study is expected to be open from October 6, 2025 to November 20, 2025. After the ISO validates your interconnection request and the cluster request window closes, the customer engagement window opens and a cluster study scoping meeting is held. A cluster study scoping meeting will address pertinent information about your project and the interconnection studies the ISO will perform to assess your project’s impact on the power system and the facilities and upgrades potentially needed to interconnect your project per all requirements and standards.
After the ISO has completed the necessary study work, you’ll work with the ISO and the transmission owner on an Interconnection Agreement (IA), a formal document detailing the terms and conditions for interconnection service. You must enter into an IA before you can construct or operate a generator or an elective transmission upgrade. Final steps of the interconnection process are to submit final data and register your asset with the ISO.
Several schedules of the ISO’s Open Access Transmission Tariff contain the rules detailing the interconnection process:
Email IRTT Participant Support at irtt@iso-ne.com, or contact ISO Participant Support.
