Entergy Corp. officially applied late Monday to turn over basic control of its power grid to an Indiana nonprofit that would link power plants from the Gulf of Mexico into northern Canada.

Entergy executives said the move would save the utility’s 1 million Louisiana customers up to $575 million.

The New Orleans company’s subsidiaries filed a joint application with the Louisiana Public Service Commission to transfer control of transmission facilities to the Midwest Independent Transmission System Operator Inc. by December 2013.

The PSC regulates utilities and approves the rates those privately owned companies can charge Louisiana customers.

Joining a regional transmission system such as MISO would better protect Entergy’s customers from blackouts and save them money, according to Bill Mohl, president and chief executive officer of Entergy Louisiana LLC and Entergy Gulf States Louisiana LLC, in a prepared statement.

MISO uses sophisticated monitoring tools, congestion-management processes and backup capabilities to ensure that power flows through the transmission system efficiently, Mohl said.

MISO also has established a “Day Two Market” that allows the utility companies to more efficiently sell excess power and buy electricity when needed, he said.

“We believe that our proposal to join MISO provides important and sustained benefits that are in the best interest of our customers,” Mohl said in a news release.

“But we realize this is an important matter involving detailed issues, and we look forward to continuing to work closely with the commission as it reviews our proposed plans for the future,” he said.

Entergy Corp. powers 2.7 million homes and businesses in Arkansas, Louisiana, Mississippi and Texas. Entergy wants to connect its 15,500 miles of transmission lines that distribute power from plants to customers with the 57,453 miles of lines controlled by MISO.

A coalition of utility companies, MISO services about 40 million people in Wisconsin, Illinois, Indiana, Iowa, Kentucky, Michigan, Minnesota, Missouri, Montana, North Dakota, Ohio, Pennsylvania, South Dakota and the Canadian province of Manitoba.

“We estimate that MISO’s well-established and mature market will result in annual benefits of $500 million across Entergy’s system, while providing the type of planning and infrastructure upgrades necessary to improve the system’s reliability,” Wayne Schug, executive director of Stakeholder Engagement and Strategic Planning with MISO, said in a prepared statement.