From the Florida coast to the Indiana Midwest: who Duke serves
Duke Energy is the largest investor-owned electric utility in the United States by transmission and distribution footprint. It serves about 8.2 million electric customers across six states (North Carolina, South Carolina, Florida, Indiana, Ohio and Kentucky) and operates roughly 320,000 miles of power lines, the largest T&D system in the country.
- The size of the Duke Energy network and the states it covers
- Why power outages happen on Duke lines
- The $103 billion investment plan from 2026 to 2030
- How self-healing technology is changing outage response across six states
Inside the largest transmission and distribution network in the U.S.
Duke operates through several regulated subsidiaries: Duke Energy Carolinas and Duke Energy Progress in the Carolinas, Duke Energy Florida, Duke Energy Indiana, Duke Energy Ohio and Duke Energy Kentucky. Each has its own state regulator, but the core grid technologies and the broader investment plan are shared across the group.
- About 8.2 million electric customers across six states.
- About 320,000 miles of transmission and distribution lines, the largest T&D footprint in the U.S.
- Duke Energy Carolinas plus Duke Energy Progress serve 3.6 million customers in North Carolina alone, with another 150,000 added over the past two years.
- Duke Energy Florida serves 2 million customers across a 13,000 square mile area with 12,300 MW of generation.
Duke Energy Corporation (NYSE: DUK) is headquartered in Charlotte, North Carolina.
Why Duke's outage causes change with the season
With six states ranging from coastal Florida to the Indiana Midwest, Duke's outage drivers vary heavily by region. Hurricanes dominate in Florida and the Carolinas, while ice storms and convective storms are bigger factors in the Midwest.
Hurricanes and tropical storms
Florida and the Carolinas regularly take direct hits from named storms. Hurricanes Helene (2024) and Milton (2024) drove some of the biggest restoration efforts in Duke's recent history. Storm surge, wind damage and flooding remain the main reasons for the longest outage events.
Severe weather outside hurricane season
Across the Midwest territories (Indiana, Ohio, Kentucky), thunderstorms, ice storms and tornadoes are the main outage drivers. The Carolinas also see ice storms in winter that can take down lines on a wide scale.
Trees and vegetation
Trees falling on overhead lines remain one of the most frequent causes of unplanned power outages on the network. Duke trimmed 43,500 miles of vegetation in North Carolina alone over the past five years.
Aging poles and equipment
Wooden distribution poles, older transformers and aging substation equipment fail more often than newer infrastructure. Replacing wood with steel or concrete poles is a cornerstone of the storm hardening program, especially on transmission lines.
The biggest grid investment plan in the U.S.
Duke is running one of the largest capital programs in the U.S. utility sector, with grid hardening, undergrounding and self-healing technology as the main pillars of the work that is reshaping outage performance across all six states.
Duke Energy capital plan and reliability results
$200 to $220 billion in planned capital investment over the next decade.
$103 billion specifically planned for 2026 to 2030.
More than $10 billion invested since 2022 on grid resilience and storm hardening.
About 400,000 wooden poles replaced or upgraded and 1,300+ miles of power lines upgraded.
2.2 million customer outages avoided in 2025 thanks to self-healing technology, saving 5.2 million hours of total outage time.
Storm bonds issued after Hurricane Helene save North Carolina customers $422 million.
Florida is the showcase territory: about 60% of transmission poles upgraded over the past five years (full completion targeted in 2028), 50% of distribution underground, and 82% of customers on self-healing technology.
In North Carolina, the share of customers on self-healing technology has tripled since 2022, reaching 75% by end of 2025. Across the six states, around 75% of all customers were covered by self-healing tech at the end of 2025.
How self-healing technology cut 5.2 million outage hours in 2025
Self-healing grid technology
Automated systems detect a fault and reroute power around the damaged segment, often in less than a minute. Duke describes this as the single biggest reliability lever currently available, and it is now deployed across roughly 75% of the customer base.
Targeted undergrounding
Duke does not bury everything (it is too expensive at scale) but targets outage-prone segments in residential backyards, dense vegetation areas, and locations exposed to repeated storm damage. Florida already has 50% of distribution underground.
Wood-to-steel pole conversion
Wooden transmission poles are being replaced with steel or concrete units that resist much higher wind speeds. Duke reports that zero non-wood poles needed replacement in the Carolinas after Hurricane Helene, a strong validation of the program.
Modern control centers and ADMS
Duke recently completed the final additions to its fleet of state-of-the-art control centers. These centers automate power restoration during storms and integrate solar, battery storage and EV charging at scale.
Smart meters and outage detection
Smart meter data lets Duke detect outages at the address level and confirm restoration without customer phone calls. This shortens event closeout after every storm.
What Duke customers can use during an outage
Duke Energy outage map
Duke publishes a public outage map per state. Customers can search by address or zip code, see the size of an outage, estimated restoration time and crew status.
Mobile app and alerts
The Duke Energy mobile app gives access to the outage map, lets customers report a power outage and pushes proactive SMS, email and app notifications when service is interrupted.
EV charging programs
Duke runs make-ready EV charging programs in several of its states, with managed charging incentives that reward off-peak charging to limit pressure on local distribution circuits.
Bill assistance
Duke participates in low-income assistance programs across all its jurisdictions, with state-specific rules and partner non-profits managing application and enrollment.
Duke's six states and their main ISPs
For a wider view of how the U.S. electric grid works and why outages happen, see the U.S. power outage page. For internet outages across Duke's six-state footprint, the most common providers are AT&T, Spectrum and Xfinity.