FERC Opinion 594 Base ROE Decision
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Regulatory Analysis

FERC Sets 9.57% Base ROE for New England Transmission Owners — What's Behind It?

In Opinion No. 594, FERC found New England Transmission Owners' 11.14% base ROE was unjust, replacing it with 9.57% — a decision with an estimated $1.5 billion in refund implications.

NewGen Cost of Capital Team

NewGen Strategies & Solutions · April 2026

On March 19, 2026, in Opinion No. 594, the Federal Energy Regulatory Commission ("FERC") found that New England Transmission Owners' ("NETO") previously effective base return on equity ("ROE") of 11.14% was unjust and unreasonable and determined that it needed to be replaced with a base ROE of 9.57%.1 Eversource Energy estimates that the refunds associated with this decision at $1.5 billion for all of the NETO entities.2 This large amount represents a financial hurdle for the NETOs to manage but also shows the extent that New England ratepayers have been overcharged for over a decade.

description In This Article

Below we provide a brief overview of the long-running saga leading to Opinion No. 594 and our more detailed review identifying nuances and insights found within the 304 page decision is made available upon request.

Overview — the Twists and Turns Leading to Opinion No. 594

This decision arrives nearly 15 years after the first of four complaints were filed against NETO's 11.14% base ROE in September 2011. As part of the long-running saga, the FERC issued Opinion No. 531 in June 2014 and later Opinion No. 531-A on October 2014, and determined that 10.57% was the appropriate base ROE for NETO.3 The 10.57% base ROE has been charged by NETO since October 2014.

These opinions reflected an important methodological change in how FERC assessed and determined ROEs for electric utilities, with the FERC moving from a one-step form of the discounted cash flow ("DCF") model to a two-step DCF model that now included both short-term and long-term growth rates. Additionally, the 10.57% base ROE was based on the midpoint of the upper half of the zone of reasonableness to account for what it characterized as anomalous market conditions.

However, it didn't end there, because in 2017, following petitions to the D.C. Circuit Court, the court remanded Opinion Nos. 531 and in response the FERC issued a briefing order in 2018 that proposed a new four-model methodology.4 At around the same time, FERC issued a similar briefing with the same proposed new methodology in relation to complaints filed against the base ROE of the Midcontinent Independent System Operator transmission owners ("MISO TO").5

Subsequently, as part of the MISO TO complaint proceeding, FERC determined a new methodological framework to determine ROEs as part of the Opinion Nos. 569 series of decisions across the 2019 and 2020 years.6 Once more as part of the case history, the D.C. Circuit Court also remanded these decisions, and the FERC issued a subsequent order on remand in the year 2024 and which was not changed in a 2025 order addressing rehearing requests.7 The base ROE determined in that last decision of 9.98% was based on the two-step DCF and Capital Asset Pricing Model ("CAPM").

FERC's Preferred ROE Methodology

Two-Step DCF

Short-Term Growth Rate

@ 80% Weight

Long-Term Growth Rate

@ 20% Weight

Dividend Yield

Adjusted by Short-Term Growth Rate

CAPM

Market Return Calc.

One-Step DCF of S&P 500 Index

Beta

Sourced from Bloomberg

Risk-Free Rate

Based on 30-Year Treasury Yield

Turning back to Opinion No. 594 for the NETO, the FERC employed the same methodological framework adopted in the MISO TO Opinion Nos. 569 decisions to arrive at its decision of 9.57% base ROE. The 9.57% base ROE was formed using financial data from the six-month study period of October 2012 – March 2013, which was related to the first complaint proceeding. Therefore, the study period is quite dated by now.

Zone of Reasonableness — Opinion No. 594

Range from lower bound to upper bound, with midpoint marked. Study period: Oct 2012 – Mar 2013.

Range (Lower – Upper Bound)
Bound Endpoints
Midpoint

The FERC also ordered refunds for the 15-month refund period associated with the first complaint and from October 16, 2014 through to the date that Opinion No. 594 was issued. Thus, the first refund component is based on the difference between the 11.14% base ROE and 9.57% ROE and the second component is based on the difference between 10.57% base ROE and 9.57% base ROE.

The Case Timeline

Sept 2011

Initial Complaints Filed

First complaint against NETO's 11.14% base ROE initiates the 15-year proceeding.

June 2014

Opinion No. 531 Issued

FERC adopts two-step DCF methodology and establishes 10.57% base ROE for NETO.

Oct 2014

Opinion No. 531-A

Follow-up opinion confirms 10.57% ROE becomes effective; applied retroactively to October 16, 2014.

2017

D.C. Circuit Remand

Court remands Opinion Nos. 531 and 531-A, questioning FERC's methodological approach.

2018

FERC Briefing Order — NETO

FERC proposes new four-model methodology in response to court remand; same process initiated for MISO TO.

2019-2020

Opinion No. 569 Series — MISO

FERC issues Opinion Nos. 569, 569-A, and 569-B establishing new two-model ROE framework for MISO Transmission Owners.

2022

D.C. Circuit Remand (MISO)

Court remands MISO decisions; FERC directed to reconsider ROE methodology on remand.

2024

MISO Remand Order

FERC issues order on remand determining 9.98% base ROE for MISO Transmission Owners using refined methodology.

March 2026

Opinion No. 594 — NETO

FERC applies same settled methodology from MISO remand decision, establishing 9.57% base ROE for NETO; $1.5B in refunds ordered.

We can reasonably expect that Opinion No. 594 will be appealed at the court and this may not be the last of the matter.

Want the Full Analysis?

Our detailed review identifies nuances and insights from the 304-page decision — including proxy group selection, natural break analysis, beta methodology, and the Commission's treatment of the Risk Premium method.

Request the Full Report →

Footnotes

1 Opinion No. 594, 194 FERC ¶ 61,208.

2 Martha Coakley, Attorney General of the Commonwealth of Massachusetts, et al., Docket Nos. EL11-66-001 et al. Motion of Central Maine Power Company et al. for a Stay of Retroactive Refund Obligations, and Request for Shortened Comment Period and Expedited Consideration, April 2, 2026.

3 Opinion No. 531, 147 FERC ¶ 61,234 (2014), Opinion No. 531-A, 149 FERC ¶ 61,032 (2014), Opinion No. 531-B, 150 FERC ¶ 61,165 (2015).

4 NETO Briefing Order, 165 FERC ¶ 61,030 (2018).

5 MISO Briefing Order 165 FERC ¶ 61,118 (2018).

6 Opinion No. 569, 169 FERC ¶ 61,129 (2019), Opinion No. 569-A, 171 FERC ¶ 61,154, Opinion No. 569-B, 173 FERC ¶ 61,159 (2020).

7 MISO Transmission Owners, et al., v. FERC, 45 F.4th 248 (D.C. Cir. 2022), MISO Order on Remand, 189 FERC ¶ 61,036 (2024) ("MISO Remand Order"), 190 FERC ¶ 61,184 (2025).

NewGen Strategies & Solutions is a utility regulatory and financial consulting firm serving electric, water, wastewater, and solid waste utilities nationwide.

© 2026 NewGen Strategies & Solutions, LLC. All rights reserved. This content is for informational purposes and does not constitute legal or financial advice.

The NewGen Cost of Capital Team

Breandan Mac Mathuna
Breandan Mac Mathuna
Principal

Breandan Mac Mathuna is a utility finance and regulatory expert with 16+ years of experience in rate structuring, cost of service, and cost of capital analysis. He has served as an expert witness before FERC and state commissions, providing financial analysis and testimony on rate of return and transmission cost recovery.

Zak Wright
Zak Wright
Partner

Zak Wright is a versatile utility finance professional specializing in appraisals, depreciation, rate design, and financial modeling for electric, natural gas, water, and wastewater utilities. He holds several industry certifications and has a proven track record of delivering strategic financial solutions.

Nick Coomer
Nick Coomer
Manager

Nick Coomer is a utility finance specialist with expertise in valuation, depreciation, financial modeling, and cost of service and rate design. As a Certified Rate of Return Analyst, he supports utilities with strategic forecasting, asset analysis, and data-driven financial planning.

Cecille Perez
Cecille Perez
Senior Consultant

Cecille Perez is a Senior Consultant specializing in regulatory analytics, financial modeling, and process automation. She supports FERC filings, ROE analyses, and transmission formula rate modeling, delivering precise, data-driven insights that enhance utility decision-making.