Regional transmission investment: Summer 2017 update
Thursday, June 29, 2017 at 12:00PM
ISO New England in Industry News & Developments, transmission planning

730 projects put into service since 2002 to fortify New England’s transmission system

The ISO recently published the June 2017 update to the Regional System Plan (RSP) Project List, which details Pool Transmission Facility (PTF) projects needed to ensure reliability in New England. Since the March 2017 update, 2 projects plus a portion of a third were cancelled, 16 upgrades were placed in service across Connecticut, Massachusetts, New Hampshire, and Rhode Island, and 2 new projects were added. Additionally, some project cost estimates changed, and in-service dates for 4 projects were moved into 2022.

About the RSP Project List

Published three times a year (March, June, and October), the RSP Project List describes the status of regional transmission reliability projects. As a part of the regional system planning process, the ISO must continually:

  • Re-assess 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

Note: The RSP Project List format was updated in May 2015 to indicate which transmission upgrades on the list are “grandfathered” and which are not, with respect to new requirements under Order No. 1000, Transmission Planning and Cost Allocation, from the Federal Energy Regulatory Commission. The new processes will not apply to proposed or planned projects on the list prior to May 18, 2015, unless the ISO must reevaluate the solution design. (Concept projects aren’t grandfathered.) See the May 18, 2015 update for more.

Since 2002, a cumulative total of 730 project components representing an investment of $8.4 billion have been placed into service to help ensure that New England’s transmission system continues to reliably and efficiently move wholesale electricity across the region.

As of June 2017, the update presentation lists 137 active projects across all six New England states. This includes:

The estimated cost of active future projects through 2021 totals approximately $4 billion.


In addition to helping ensure the region can count on the electricity it needs every minute of every day, transmission system upgrades also help lower wholesale electricity costs and enable the development and use of cleaner energy resources. Improving the movement of electricity across the region and into areas of limited transmission and high demand:

Tempering factors

Regional energy trends can affect transmission needs. For example, the New England states are national leaders in energy-efficiency (EE) policies and programs. EE savings—when coupled with new generators and other transmission upgrades—may allow the region to defer certain transmission projects deemed necessary to address reliability needs.

With their continued expansion, solar photovoltaic (PV) resources and other forms of distributed generation may also one day be able to alleviate or prevent constraints in regional power system transmission or distribution, and reduce or eliminate the need to install new transmission or distribution facilities.

Additionally, market resource alternatives (MRAs)—such as new generators or demand-response resources—may in some cases be able to help alleviate transmission needs. The ISO has performed MRA analysis on select portions of the system to help signal to developers and stakeholders where these opportunities exist.

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Article originally appeared on ISO Newswire (
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