ATTORNEY GENERAL Andrea Campbell said a new study by her office indicates electricity retailers in Massachusetts finally saved their customers some money, but she continues to insist the industry should be shut down because the savings were so small.

Campbell released an updated report on the competitive electricity market that indicated customers in seven of the last eight years paid more for electricity than they would have if they let their utility buy their power for them. In the eighth year, running from July 2022 through June 2023, the retailers saved their customers a total of $30.4 million, but Campbell’s report said she expected the savings to be much higher because the utility rates, called basic service, soared because of volatility in energy markets.

“Record-high basic service rates should have presented the perfect opportunity for the individual residential electric supply market to deliver on its promises and provide customers with the benefit of significant savings,” the report said. “Analysis of the actual rates charged by suppliers to their customers during this timeframe, however, reveals a broken and predatory market that continues to harm customers, and low-income customers in particular.”

Campbell’s study is the latest salvo in an escalating battle on Beacon Hill between electricity retailers who want to stay in business and politicians, led by Campbell and Gov. Maura Healey, who want to shut them down.  The battle is expected to come to a head in the next few months in a still developing climate bill that has yet to take shape; the two chairs of the Legislature’s Telecommunications, Utilities, and Energy Committee are split on the issue.

On electric bills, all customers pay a wide variety of regulated and standard delivery and transmission charges to have electricity delivered to their homes, but they have the freedom to choose their actual electricity supplier. They can choose one on their own, join with other members of their town or city if their municipality aggregates its residents into a buying unit, or go on basic service, where the utility purchases electricity on their behalf, acting as a middleman and taking no profit itself.

Campbell aides say the latest report was conducted the same way previous ones were done, using data provided by the state’s utilities, which handle all billing of customers. All of the money spent purchasing electricity from retailers was added together and divided by the number of customers on those rate plans to get an average rate, which was compared to what those customers would have paid had they remained on the utility’s basic service.

The latest report showed those consumers would have saved $82.8 million had they been on basic service from July 2021 through June 2022, but the report indicated they saved $30.4 million by using the retail suppliers in the next year, the first time that has happened in the eight years the attorney general’s office has been tracking the market. Over that eight-year period, the attorney general’s office said, customers of electricity retailers could have saved $577.6 million by remaining on basic service.

Campbell and others who side with her accuse the companies of deceiving customers by going door to door peddling what amount to higher-cost plans. They accuse the companies of preying on lower-income customers and customers of color.

But a number of the electricity retailers lumped into this group are branches of respected companies that actually sell power to municipal aggregators, which are often hailed for saving their customers money when compared to basic service.

Boston, for example, uses Direct Energy as the electricity supplier for its aggregation, called Boston Community Choice Electricity. Direct Energy offers two plans to members of the Boston aggregation that are cheaper than basic service and one, for 100 percent clean energy, that costs a bit more. (Basic service has only 24 percent renewable energy.)

Direct Energy also markets similar plans to individual consumers. The plans vary in length and renewable energy content. Those plans would be banned if Campbell succeeds in shutting the retail market down.

The attorney general’s blunt financial analysis doesn’t take into account nuances of electricity sales. For example, basic service offers a vanilla electricity package at rates that change every six months, while retail suppliers offer a whole host of options on length of contract as well as renewable energy content. They also offer plans that allow customers to consume unlimited amounts of electricity for one flat monthly rate. A flat rate would come across in the attorney general’s analysis as an expensive rate even though, on a cost-per-kilowatt-hour basis, the rate might be reasonable.

Christopher Ercoli, the president and CEO of the Retail Energy Advancement League, one of two groups representing electricity retailers, said the attorney general’s latest report misleads the public and the Legislature.

“We’ve continued to share with the attorney general that there are inconsistencies in reporting, including comparing basic power products from the utility to renewable products and value-added products from suppliers,” Ercoli said in a statement. “Despite this, the data still shows that the competitive market shields consumers from rate shock, a crucial point the author fails to emphasize. Massachusetts customers have spoken loud and clear, they prefer the freedom to shop for power, rather than being subjected to price uncertainty and limited renewable options from the incumbent utility.”

The retail electricity industry, which currently serves roughly 400,000 customers in Massachusetts, has endorsed legislation filed by Rep. Tackey Chan of Quincy that the lawmaker says would address deficiencies in the industry. It includes new industry licensing fees that could be used to support greater oversight and enforcement.