An August 2026 study, Powering Growth and Affordability: The Role of Transmission in Economic and National Security, prepared by S&P Global’s CERA Consulting for the Electricity Customer Alliance (ECA), National Grid and Converge Strategies, contends that 13 “high value” inter- and intraregional transmission projects in the Eastern Interconnection could produce up to $15.3 billion in net system value through 2050. These projects have the potential to lower retail electricity rates, enhance system reliability and improve resilience to extreme weather events.

The significance of this study lies in its “customer-centric” point of view regarding transmission expansion, according to Jeff Dennis, ECA executive director. “Customers need more transmission capacity. But they’re in this conundrum because they see transmission costs going up,” he said.

Dennis blames rising costs on supplemental projects in the PJM Interconnection and local builds in other regions. He says this study shows how to address that by refocusing attention on transmission that provides the most net benefits. Furthermore, the study reinforces findings from the U.S. Department of Energy and other researchers showing that targeted transmission projects between and inside regions can lower costs because they create pathways enabling lower cost electricity to flow to higher-cost areas.

Transmission links also save money by eliminating the need to build more power plants and local transmission.

The study evaluated potential transmission lines in the Northeast, the PJM Interconnection, the Southeast, the Midcontinent Independent System Operator’s southern region and the Southwest Power Pool. Both base demand and high-demand cases were modeled, using constrained and unconstrained transmission scenarios.

It identified 12 potential high-value transmission projects under the base demand case and 13 projects under the high-demand case.

“The biggest contributor to NPV is [a change in generation capital expenditures], followed by production cost savings and avoided transmission costs, as transmission expansion enables access to lower-cost remote resources, reducing the need for more expensive local generation builds,” the study’s authors wrote.

According to the study, in the unconstrained base demand cases, the benefits each group would receive over 40 years is substantial:

• PJM: $6.7 billion
• SPP and MISO South: $1.9 billion each
• Southeast: $851 million 
• Northeast: $393 million

Benefits are escalated in the high-demand scenario, especially in the Northeast and Southeast. The study also determined that advanced transmission technologies, such as dynamic line ratings, could produce significant benefits that could offset initial costs.

One idea to incentivize interregional transmission development is to allow large customers to invest directly, opening opportunities for merchant transmission and permitting, Dennis said.