In accordance with Attachment K, Section 17 of the ISO’s Open-Access Transmission Tariff (OATT), the ISO performs Economic Study analyses to inform stakeholders about potential future versions of the regional grid.
They allow the ISO and stakeholders to evaluate possible upgrades or investments that may reduce production costs to serve system load, alleviate transmission congestion, or enable the integration of new resources or loads.
Economic studies also provide a structured process for stakeholders to examine key regional issues across a range of hypothetical future scenarios. These modeled futures are not development plans, nor do they reflect the ISO’s preferred vision of system evolution. Rather, they are analytical tools intended to support long-term planning discussions and foster engagement. To date, the ISO’s Economic Studies have focused heavily on the integration of renewables and zero-carbon dispatchable technologies, or increased transfers with neighboring power systems.
As of 2024, each economic study cycle examines four reference scenarios, each designed to address different planning needs:
Models the previous calendar year and compares the simulation results to historical system performance. This scenario validates and improves the accuracy of modeling tools and inputs.
Model future years beyond the 10-year planning horizon, with an emphasis on meeting New England’s carbon dioxide emissions reduction targets.
Models the system ten years into the future based on the ISO’s existing planning criteria to identify system efficiency issues on the Pool Transmission Facilities (PTF) portion of the New England Transmission System and, as applicable, evaluate competitive transmission solutions to alleviate those issues.
Models a scenario based on a stakeholder request that falls outside the scope of the other three scenarios or their sensitivities.
A stakeholder may request the ISO perform a Stakeholder Requested Sensitivity or Scenario via the Planning Advisory Committee (PAC) during certain windows in a study cycle.
The scope of work, assumptions, and results of an economic study reflect input from the PAC.
Economic study-related information is accessible below. Use the Key Topic filter to sort materials by Economic Study Planning Year. Use the Document Type filter to find specific types of materials.
Key materials of interest include:
