Earnings at power companies face review by customers, advocacy organisations, and oversight bodies, with Maine among the states where that scrutiny has taken hold. Utility providers granted exclusive rights to serve defined geographic areas face caps on the investment returns they are permitted to earn, given that no competing suppliers exist to discipline pricing through market pressure. Power companies have argued that preserving elevated profit margins is necessary to draw the capital needed for dependable infrastructure, particularly as the electrical grid faces mounting strain from shifting climate conditions.
Settling on an acceptable level of profit can draw out negotiations and legal proceedings for months or even years. A rate proposal filed by Central Maine Power — one that would raise the company's allowed return on equity — has drawn considerable attention throughout the year. Utility-rate rule changes have been taking shape through a process that unfolded outside public scrutiny, even as regulators continue to weigh the separate petition.
Regulatory bodies at both the state and federal levels have moved to place caps on what electricity transmission operators can earn. A ruling from the Federal Energy Regulatory Commission, handed down earlier this year, directed transmission utilities across New England to return in excess of $1.5 billion to ratepayers, following a determination that the profit margins those companies had been permitted to earn were pegged at levels above what regulators considered appropriate. Court filings remain active as the utility companies contest the matter.
State regulators in Maine petitioned the federal authority to eliminate an incentive that had also expanded profit opportunities for utility companies — a move that prompted several of those firms to file lawsuits against the state.
Strung between generating facilities — whether conventional power plants or renewable wind and solar installations — and neighbourhood distribution substations, high-voltage transmission lines move electrical power across spans that can stretch for considerable distances. From that junction, a finer lattice of distribution lines fans outward, carrying power through to homes, businesses, and the full range of other destinations drawing on the grid. Oversight of the network splits along jurisdictional lines: the interstate transmission infrastructure falls under the authority of the Federal Energy Regulatory Commission, whereas distribution operations confined to Maine answer to the Maine Public Utilities Commission.
Three entities hold transmission ownership across Maine — Central Maine Power, Versant, and the Maine Electric Power Company, a joint venture the two utilities operate together. Two separate utilities divide Maine's geography between them — Versant holds responsibility for the eastern and northern reaches, while Central Maine Power handles the southern and central portions of the state. A transmission link operated by Maine Electric Power Company runs between the state of Maine and the Canadian province of New Brunswick.
A formal complaint lodged with the Federal Energy Regulatory Commission in 2011 by the Maine Office of the Public Advocate and allied consumer groups took aim at the 11.14% authorised return on equity that New England transmission line owners had been permitted to collect, arguing the figure exceeded what was justifiable. Utility shareholders earn a return on equity — a financial yield tied to the capital they put in — that in turn funds the construction and upkeep of power and water infrastructure.
Following a drawn-out regulatory dispute spanning multiple rounds, the Federal Energy Regulatory Commission handed down a ruling in March of this year that upheld its previous determination, setting the permitted return on equity at 9.57%. Transmission line owners were directed to pay back the pricing difference to affected customers on a retroactive basis, with that repayment due no later than May 2027. Roughly $130 million of that $1.5 billion pool is earmarked for Maine-based customers seeking refunds.
Heather Sanborn, who holds the Maine public advocate post, put the likely benefit to a typical residential customer at around $20 a month spread across a 12-month period. Additional data from the companies themselves would be needed to arrive at a more precise figure, she noted.
A June ruling by the Federal Energy Regulatory Commission drew a formal appeal from Central Maine Power, Versant, and other transmission owners operating across New England. Versant put forward a refund proposal the following month, and ISO New England is now overseeing the reimbursement process while that plan sits before FERC, pending a decision on approval. Further details are expected to become available once FERC hands down its ruling.
In an emailed statement, Versant spokesperson Marissa McKay clarified that the matter pertains exclusively to transmission customers within the company's Bangor Hydro District, leaving Maine Public District customers unaffected. The spokesperson left the question of how the company's appeal involvement might affect refund timelines unanswered, noting only that ongoing legal proceedings prevented any comment and that advancing customer refunds — pending FERC approval of the proposal — remained the organisation's priority. No statement on the active lawsuit was forthcoming from Central Maine Power.
Legislation enacted by the Maine Legislature in 2025 placed an obligation on utilities to join ISO New England, the regional transmission organisation overseeing the area's power grid. In handing over that authority, the utilities cede day-to-day command of their transmission networks to ISO New England, which then coordinates and directs grid operations across the region. Membership in ISO New England had been voluntary for the utilities, which collected a half-percentage-point addition to their approved return on equity as compensation for taking part.
Three Maine agencies — the Office of the Public Advocate, the Public Utilities Commission, and the Department of Energy Resources — brought a formal complaint before the Federal Energy Regulatory Commission, arguing that a particular rate adder had become a relic given the utilities' current mandatory membership in ISO New England and should therefore be removed. Projected yearly savings for Maine ratepayers top $2 million, according to figures put forward by consumer advocacy groups. Versant has indicated it will not contest Maine's petition to remove the adder.
Facing a newly passed state law they sought to overturn on constitutional grounds, Central Maine Power and the Maine Electric Power Company brought a federal lawsuit against Sanborn, Philip Bartlett, and Celina Cunningham — the three agency heads who had filed the original complaint — seeking both to invalidate the legislation and to prevent those officials from carrying out its provisions. The companies contend that Maine has stepped into territory reserved for federal regulators, asserting in their court filing that the statute was enacted solely to pressure a change to a rate that falls under the jurisdiction of the Federal Energy Regulatory Commission; they further stated that the regulation's financial consequences are considerable, materially reducing their ability to recover the full return on equity they are owed and on which they depend for the capital needed to maintain and upgrade transmission infrastructure, preserve system reliability, and sustain the contractual arrangements underpinning their relationship with ISO-NE.
Electricity bills for Maine customers extend well beyond transmission line charges alone — a broader analysis from the Office of the Public Advocate found that total rates paid by those customers climbed 72 percent across a six-year span. Monthly bills for Central Maine Power customers in central Maine climbed from roughly $91 to $157 between October 2020 and October 2026, a jump that Sanborn attributed to a combination of factors rather than any single cause, noting that utilities upgrading older infrastructure — while a contributor — account for a smaller share of the increase than the other pressures pushing electric rates upward.
Among the various elements that push up overall utility bills, charges tied to infrastructure upkeep — particularly those stemming from weather-related damage — tend to carry the heaviest weight. Natural gas prices, more than any other input, account for the upward pressure on what households and businesses pay for electricity. Growing adoption of heat pumps, electric vehicles, and similar technologies is projected to place greater strain on the power grid. Shifts in weather patterns tied to a changing climate are placing growing pressure on the infrastructure that keeps the grid running.
Sanborn put forward the view that managing when electricity gets used — spreading consumption across the day and year rather than concentrating it in peak windows — offers the most practical path to keeping power both affordable and dependable, and she noted that distribution, transmission, and supply infrastructure all have to be sized to handle those heaviest-demand periods. Sanborn also put forward the view that growing battery storage alongside renewable capacity could ease strain on the grid, while time-of-use pricing — an opt-in programme offered through both Central Maine Power and Versant — lets customers shift their electricity use toward off-peak windows; her stated rationale is that drawing more value from existing infrastructure by distributing its output across a larger number of kilowatt hours throughout the year has the potential to keep rates from climbing.
