BOSTON — Massachusetts Attorney General Maura Healey is calling for an end to competitive electricity suppliers, saying they target low-income, elderly, and minority residents with false promises of cheaper electric bills.

The Democrat said Thursday that a two-year study conducted by her office found Massachusetts customers who switched to a competitive electricity supplier paid nearly $177 million more than if they had stayed with their utility company.

Healey said competitive electricity suppliers promise big energy savings but are actually burdening customers with hundreds of dollars in extra costs.

Healey said the average low-income customer who enrolled with a competitive supplier paid $231 more than if the customer was receiving their electricity from their utility company.

The report found some low-income households lost more than $541 by switching to a competitive supplier.