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TVA grid-wide is roughly 60% fossil (coal-fired), 30% nuclear, and 10% hydro.
The Paradise Fossil Plant is nearest to C KY, so would be fair to assume most of his power is, in fact, from a coal-fired plant.
It's now been 5-6 years since I was last at Paradise when was supporting an R&D effort to evaluate a new type of on-line elemental analyzer to aid in their attempts at blending much higher percentages of western low-sulfur coal. I presume but don't have recent data that trend continues as well as adding scrubbers on at least one unit was in the works.
All the info on the TVA grid is available at