Duke Energy Asks State, Federal Regulators for Permission to Combine Its Two Electric Utilities in Carolinas

(Photo courtesy of Duke Energy)

Duke Energy on Aug. 14, 2025, asked state and federal regulators for permission to combine its two electric utilities in the Carolinas.

Planned for years, the combination is projected to result in billions of dollars in customer savings, Duke Energy officials said.

Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP) have operated as separate utilities since the 2012 merger of Duke Energy and Progress Energy.

Although legally considered a merger, the proposed combination is more in line with reorganizing two corporate divisions into one, the officials said.

They added the strategic reorganization will create a single utility, streamlining operations and significantly reducing costs for customers.

Subject to approval, the targeted effective date of the combination is Jan. 1, 2027.

“Combining our two utilities reduces customer costs, simplifies operations, supports economic growth and promotes regulatory efficiencies, all of which will create value for customers in both states," said Kodwo Ghartey-Tagoe, executive vice president and CEO of Duke Energy Carolinas.

Ghartey-Tagoe added, "There will be no immediate changes to retail customer rates or services. We look forward to sharing more details with our customers on how rates will evolve over time if the combination is approved by regulators."

Duke Energy is modernizing its infrastructure to meet the Carolinas' growing energy needs, while ensuring customers continue to have reliable service at the lowest reasonable cost.

• Company officials said operating as a single utility would allow DEC and DEP to meet the growing needs of the Carolinas at a much lower cost. Combining the two utilities would result in more efficient planning across the utilities' combined 52,000-square-mile service area in the Carolinas, avoid redundant investments, improve grid reliability and more, the officials said.
• The officials added a combination allows Duke Energy to build fewer resources to meet growth needs than would be required if DEC and DEP continued as separate utilities. And spreading infrastructure investments over a larger customer base helps moderate the impact on rates, the officials said.
• The combined companies will also be able to operate existing resources more cost-effectively by running fewer and less expensive units, using less fuel, and reducing unit cycling on and off, saving maintenance costs, the officials said.
• Approvals are required from the North Carolina Utilities Commission, the Public Service Commission of South Carolina and the Federal Energy Regulatory Commission, which will continue to oversee and regulate the combined utility.

Company officials said Duke Energy evaluated the customer benefits of operating as a single, combined utility versus continuing to operate as two separate utilities. Duke Energy projects retail customer savings of more than $1 billion through 2038, after any expenses.

The savings are projected to occur between Jan. 1, 2027 – the proposed effective date of the combined utility – and 2038, the close of the planning horizon for the 2023 Carolinas Resource Plan.

Additional customer savings would continue to be generated beyond 2038, company officials said.

No retail rates will change immediately – DEC and DEP retail rates will start to blend gradually, over time, in future rate cases and future rider filings made after Jan. 1, 2027.

North Carolina and South Carolina will continue to regulate retail rates separately and will have independent discretion over the pace of retail rate integration.

As part of the 2012 merger of their holding companies, Duke Energy and Progress Energy received regulatory permission to jointly dispatch power generation resources in the Carolinas.

• Joint dispatch, fuel savings and other efficiencies have produced more than $1 billion in cumulative savings for customers, company officials said. But regulations limit further coordination between the two utilities; only a full combination can unlock additional savings, the officials said. 
• Since the 2012 merger, Duke Energy has completed years of operational alignment and consolidation efforts, such as building out advanced metering infrastructure and industry-leading customer, energy and distribution management systems.

According to company officials, the benefits of operating as one utility:

• New generation and transmission: A combined utility can more effectively plan, execute and operate new generation and transmission in the Carolinas, locating new assets where they make the most sense across a broader geographic footprint.
• Better generation reliability: A combination will strengthen reliability by improving the balancing of distributed generation resources while reducing the need to restrict solar production due to oversupply, grid congestion or lack of demand.
• Less confusion: A combination will enable a more uniform approach in programs, services and rates. The company will implement changes – like simplifying rates and service offerings – over time with the goal of reducing customer confusion. 
• More regulatory efficiencies: With two utilities each operating across two states, Duke Energy must maintain four retail rate structures, produce four separate annual filings – like those related to fuel costs – and more. A combination will reduce the time and expense of this regulatory compliance work by eliminating duplicative filings and proceedings.

Over the past 13 years, most corporate functions were merged, but the planning and operation of the respective power grids and generation resources in the Carolinas remained separate.

Company official said the combination of electric utilities will allow the company to operate more efficiently as a single provider in the Carolinas, benefiting customers and enabling energy modernization at a significantly lower cost than would otherwise occur.

Duke Energy Carolinas, a subsidiary of Duke Energy, owns 20,800 megawatts of energy capacity, supplying electricity to 2.9 million residential, commercial and industrial customers across a 24,000-square-mile service area in North Carolina and South Carolina.

Duke Energy Progress, a subsidiary of Duke Energy, owns 13,800 megawatts of energy capacity, supplying electricity to 1.8 million residential, commercial and industrial customers across a 28,000-square-mile service area in North Carolina and South Carolina.