Ayni — Analysis — North Carolina's Grid Grew by 10 Terawatt-Hours in Fifteen Years. Duke Energy's Own Plan Has It Growing by 80 in the Next Fifteen.

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North Carolina's Grid Grew by 10 Terawatt-Hours in Fifteen Years. Duke Energy's Own Plan Has It Growing by 80 in the Next Fifteen.

Electricity demand across Duke Energy's Carolinas system grew by roughly 10 terawatt-hours over the past 15 years. Duke's own 2025 Carolinas Resource Plan, filed with regulators, projects demand growing by another 80 terawatt-hours over the next 15 -- an eightfold acceleration, almost equal to South Carolina's entire statewide electricity consumption in 2023. More than 85% of that new load is data centers: Duke signed 2.7 gigawatts of new data-center agreements in Q1 2026 alone, on top of a 7.6-gigawatt contracted pipeline and another 7.8 gigawatts in late-stage negotiation, for a combined 15.4-gigawatt pipeline. The plan Duke filed to serve it is specific and dated -- five new combined-cycle gas units including two in Person County, NC, immediately adjacent to the Research Triangle; seven new combustion turbines across Catawba, Rowan, and Richmond counties; nearly 300 megawatts of nuclear uprates at four existing stations, on top of a fleet that just posted a record 96.9% capacity factor; and an entirely new reactor targeted for 2037. Battery storage and solar targets both rose sharply from the 2023 plan, customer bills are projected to rise roughly 2.1% a year, and North Carolina's own utilities commission won't issue a final order on the plan until December 31, 2026. The Research Triangle's life-sciences boom and Duke's resource plan are the same story from two different desks -- one counting factories, the other counting megawatts.

Start with Duke Energy's own numbers, not a summary of them. Electricity demand across Duke's Carolinas system grew by roughly 10 terawatt-hours over the past 15 years. The company's own 2025 Carolinas Resource Plan, filed with regulators, projects demand growing by another 80 terawatt-hours over the next 15 -- an eightfold acceleration, almost equal to South Carolina's entire statewide electricity consumption in 2023 (81 terawatt-hours), added on top of a system that already exists.^[1]

More than 85% of that new load is data centers, and the pace is still accelerating in real time.^[1] Duke signed 2.7 gigawatts of new data-center energy agreements in the first quarter of 2026 alone, bringing its cumulative contracted pipeline to 7.6 gigawatts -- nearly two-thirds of it already under construction -- with another 7.8 gigawatts in what the company calls "high-confidence, late-stage" negotiations, for a combined 15.4-gigawatt pipeline.^[4] Not every one of those megawatts is guaranteed to land -- energy reporters covering the buildout have flagged real skepticism about whether every announced data-center project gets built at the scale forecast^[5] -- but the number Duke is planning against is already large enough to reshape the grid on its own.

10 TWhthe Carolinas' electricity demand growth over the past 15 years

80 TWhDuke Energy's own projected growth over just the next 15

15.4 GWDuke's combined contracted-plus-pipeline data-center load as of Q1 2026

Duke's response is already filed with specific counties attached, not a placeholder. The plan calls for five new combined-cycle gas units -- two in Person County, NC, immediately adjacent to the Research Triangle, one in Anderson County, SC (a $3.2 billion plant with hydrogen capability, construction targeted for 2027), and two more at a site not yet chosen -- plus seven new combustion turbines split across Catawba, Rowan, and Richmond counties in North Carolina.^[2]^[4] If approved in full, the fossil-fuel additions alone total roughly 12.3 gigawatts of new capacity by 2040.^[1]

Nuclear is doing real work in the plan too, on two different timelines. Near-term, Duke is adding nearly 300 megawatts of clean capacity through uprate projects at four of its existing nuclear stations^[2] -- part of a fleet that just posted a record 96.9% capacity factor in 2025 across 11 reactors at six sites, its best reliability year on record.^[3] Further out, the plan targets an entirely new reactor entering service in 2037, either a small modular reactor at Belews Creek, NC, or a large light-water reactor at the W.S. Lee site in Cherokee County, SC.^[2]

Battery storage and solar targets both moved up sharply from Duke's 2023 plan, and none of it is free. Storage rises to 5,600 megawatts by 2034 -- 2,900 megawatts more than the prior plan called for -- and solar to 4,000 megawatts the same year, while a planned expansion of Bad Creek pumped storage was pushed back from 2034 to 2040.^[2] Duke projects the buildout raising customer bills by roughly 2.1% a year over the coming decade.^[2] And a filed plan doesn't get built just because it was filed: South Carolina's utilities commission already granted final construction approval for the Anderson County plant in April 2026, but North Carolina's own commission isn't expected to rule on that same facility until the fourth quarter of 2026, and won't issue a final order on the full Carolinas plan until December 31, 2026.^[2]^[4]

The physical layer underneath the piece this site just published on Research Triangle Park Biogen's $2 billion factory expansion, Fujifilm's $3.2 billion Holly Springs plant, and Novo Nordisk's $4.1 billion Clayton expansion don't run without power, and most of the capacity to run them doesn't exist yet. Duke's resource plan is the accounting for what the Triangle's own investment boom actually requires underneath the announcements -- filed the same year, moving through the same state, on its own separate regulatory clock. The Research Triangle Park piece is here.

The Triangle's $10.8 billion investment year and Duke's own resource-plan numbers are two departments describing the same event -- one counting factories, the other counting megawatts. The factories already broke ground. Whether the power underneath them clears a regulator's desk on Duke's own timeline is now just as material to the region's future as any single groundbreaking.

The takeaway Duke Energy's own 2025 Carolinas Resource Plan projects electricity demand growing by 80 terawatt-hours over the next 15 years -- an eightfold acceleration from the roughly 10 terawatt-hours of growth over the past 15, and almost equal to South Carolina's entire 2023 electricity consumption added on top of an existing system. More than 85% of that new load is data centers, with Duke's contracted-plus-pipeline data-center load reaching 15.4 gigawatts as of Q1 2026. The filed response is specific: five new combined-cycle gas units (two in Person County, NC, next to the Research Triangle), seven new combustion turbines, nearly 300 megawatts of nuclear uprates on a fleet that just hit a record 96.9% capacity factor, a new reactor targeted for 2037, sharply higher battery and solar targets, and a projected 2.1%-a-year rise in customer bills. North Carolina's utilities commission won't issue a final order until December 31, 2026. This is the power-grid accounting underneath the Research Triangle Park investment boom this site just covered -- the same regional story, filed on a separate, dated regulatory clock.

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