AN ALREADY LONG, TUMULTUOUS process on Beacon Hill to rein in the state’s soaring energy costs has now landed in the Senate, where the chamber’s energy chair is eyeing major changes to proposals approved by the House earlier this year.

Sen. Michael Barrett, a Democrat who leads the energy committee, told CommonWealth Beacon in an interview that the roughly $9 billion in ratepayer savings the House legislation projects to achieve over the course of a decade is “the number to meet or beat.”

“I don’t think my colleagues are going to want to offer less,” he said.

One thing, though, appears clear: Those savings will not be coming from significant cuts to Mass Save, if Barrett has his way.

Mass Save, the state’s energy efficiency program, “passes the test,” Barrett said in his most extensive comments about the legislative deliberations since the House advanced the measure.

The program, a collaboration among the utilities with state oversight, funds home weatherization projects and heat pump installations at low or no cost to reduce energy usage and utility bills over the long term. Because it’s paid for through a fee tacked onto ratepayers’ monthly bills, its budget has become a target for legislators and policymakers looking to alleviate rising energy costs.

The House voted in February to cut Mass Save by $1 billion, one of the most controversial components of the sprawling energy affordability legislative package originally proposed by Gov. Maura Healey last May. The Department of Public Utilities already reduced the program’s proposed budget by $500 million last year.

Even though Mass Save is a relatively small part of the typical utility bill, unlike complex supply and distribution costs, it is one of the few pieces of energy costs that Beacon Hill has directly in its control amid a clamoring from residents for help.

Barrett’s support for the program – and rebuke of the House push to cut what leaders in that chamber say has become a bloated initiative at great cost to ratepayers – signals an early flash point in what will eventually become a negotiation between the two chambers.

“We’re hearing a deluge of support for energy efficiency spending,” Barrett said. “I can tell you that we are doing a lot of due diligence on the question. We want to make sure that the dollars are being spent well and saving people more money. I can’t find any serious waste, and I’ve been looking hard.”

Barrett also appears unconvinced by another core piece of the House measure, a proposal to return 70 percent of so-called alternative compliance payments (ACP) made by the utilities to ratepayers, which can total north of $100 million a year. That money currently supports initiatives like the Massachusetts Clean Energy Center and the Green Communities grant program, which helps cities and towns fund renewable energy projects. It is also the fund that Healey tapped to issue temporary energy relief for residents this winter.

A “small army” of beneficiaries of ACP funds, however, has been making their voices heard of late, Barrett said.

“That makes an impression around here,” he said. “We’re taking meetings with everybody, critics and supporters alike.”

It’s still not exactly clear when the Senate will move forward with its version of the energy legislation, Barrett said, but it appears likely to come after the Senate tackles its version of an annual state budget in May.

Energy affordability has emerged as the top household concern in Massachusetts, according to a survey released this winter by business groups, and the financial pinch is growing as war in Iran drags on. That has pushed state officials to scramble to find savings for Massachusetts ratepayers, who pay some of the nation’s highest energy costs, while juggling rising power demand and ambitious climate commitments.

That green energy transition, which requires a significant and swift influx of renewable power to displace fossil fuels as the primary source of electricity, has been made even harder by the Trump administration blocking permits for offshore wind projects.

Finding consensus on how best to strike that balance has proven fraught. Healey filed her energy affordability legislation, which kickstarted this process, almost a year ago following a cold winter and rising utility bills in 2025.

But it’s been mired in infighting since House energy chair Mark Cusack, a moderate Democrat, told CommonWealth Beacon of his plan to weaken the state’s 2030 climate commitment to cut greenhouse gas emissions in half compared to 1990 levels, which advanced from committee in November. House leadership quickly scuttled that effort after it generated fierce backlash from environmental advocates.

Barrett, who was at times at odds with Cusack’s predecessor atop the House energy committee, Rep. Jeff Roy, reflected only briefly on that explosive flare-up six months ago in the House.

“You don’t look back,” Barrett said of Cusack’s earlier draft that caught many in the State House off guard. “But I can tell you this: The climate movement is alive and well in Massachusetts, as Trump and his influence and impact fade and the more traditional values of the state reassert themselves. People are very concerned about the pocketbook issue and very concerned about the climate. We ought to be able to come through on both of those priorities.”

Still, it remains unclear how exactly Barrett plans to deliver the substantial ratepayer savings that the House promises as the Senate version of the bill continues to take shape. He floated the idea of reforming the Gas System Enhancement Program, or GSEP, which allows the gas companies to recover costs from ratepayers for fixing leaky pipes, though he didn’t provide specific details of the changes he might pursue.

Spending under that program has ballooned since it took effect in 2014, even though the actual amount of pipe that’s been fixed has stayed relatively flat, which critics point to as all the more reason to move quickly away from natural gas for home heating and cooking.

“I’m hearing from a lot of senators who are indignant that GSEP has gone from an occasional resort to deal with high-risk leaks to the default funding preference for every gas construction project that comes down the pike,” Barrett said. “Something has gone wrong in terms of the overuse of that program.”

Incorporating a provision included in Healey’s original measure that could deliver savings but was left out of the House legislation may also be an option to lower energy bills. Healey’s proposal advocated for “securitization” as a possible low-interest way to finance infrastructure projects from the utilities, which could reduce the overall cost to customers in their monthly bills.

Though these areas of disagreement may portend a messy conference committee to hash out the differences between the eventual House and Senate versions of the bill, one area of common ground appears to be a crackdown on competitive electric suppliers.

The House, somewhat unexpectedly, delivered a breakthrough on that issue by allowing municipalities to ban an industry that’s been allegedly ripping off customers through deceptive practices to the tune of more than $700 million over the past decade, according to Attorney General Andrea Campbell’s office.

“I’m impressed with where the House is going on competitive supply,” Barrett said in a prior interview. “Without doubt, the Senate is going to want to contribute some ideas of its own. But at the end of the day, you could see a nice hybrid emerge.”