Why does Duke Energy’s carbon plan shortchange solar?

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Duke Energy's carbon plan for North Carolina is under regulatory scrutiny for allegedly underestimating solar and battery storage potential while proposing 2 gigawatts of new gas plants. Critics including the Southern Alliance for Clean Energy, NCSEA, NRDC, and Sierra Club argue Duke's modeling artificially caps solar deployment and favor more expensive technologies that benefit Duke's rate base, while independent studies show a solar-heavy portfolio could save $700 million to $860 million by 2030.