Connecticut officials are closing a two-year investigation into Energy Plus Holdings LLC, one of the state's electricity suppliers, in exchange for a $4.5 million payment to increase state enforcement of the rules governing competitive power markets.

The settlement, announced Thursday, involves no finding of wrongdoing and releases Energy Plus, a subsidiary of NRG Energy, and its officers from claims made against it by Attorney General George Jepsen and Consumer Counsel Elin Swanson Katz.

In 2012, the officials took issue with Energy Plus solicitations for electricity generation that they said could lead reasonable consumers to think they would receive some benefits and competitive power prices. Instead, some consumers ended up paying more than double the standard utility rate for electricity and complained about having difficulty getting information from Energy Plus.

This winter, for example, the average residential customer of Energy Plus paid nearly 14 cents per kilowatt hour, according to regulatory disclosures analyzed by The Courant, while the standard utility rate was closer to 9 cents. The company has about 6,000 residential customers in Connecticut.

A number of investigations by regulators remain open, looking into operations and marketing by North American Power, CT Gas & Electric, Starion and Direct Energy.

In a statement, Jepsen said, "With this settlement, we are agreeing to disagree with the company regarding any finding of fault in its past behavior."

The settlement funds will go to the state Public Utilities Regulatory Authority to both enforce the new and existing rules governing the third-party electricity supply market and educate consumers on how to get the best rates from quality companies. The agreement is pending regulatory approval.

The funds have already been allocated to regulators through a state budget document.

The state's General Assembly also passed a set of new regulations for the electricity supply market, requiring new notifications about rates, elimination of termination fees for variable rate plans, and quicker switching between suppliers.

Consumer Counsel Katz said: "It's been a rough year for many customers of electric suppliers, and I'm glad we can bring them some good news. Between these new resources and the new law enacted by the legislature earlier this month, we're looking at a changed landscape for this market."