AEP and the first 765-kilovolt lines (late 1960s)
AEP energized the first 765-kilovolt transmission in the United States, a voltage class that moves far more power per line than the 345-kilovolt circuits it replaced. The company built those lines across the Ohio Valley and has kept the lead: it now owns about 90% of the nation's existing 765-kV mileage.
The extra-high-voltage backbone let AEP move power between its own generating stations and neighboring systems at a scale smaller utilities could not match.
That network became the platform every subsequent AEP transmission expansion extends, and the reason a single utility can now plan a near-tripling of 765-kV mileage.
The Piketon project is three more 765-kV lines on the same backbone, each adding roughly 3.2 GW of capacity.
