Duke Energy announced Monday that Joyce Mullen will join its board of directors, effective immediately. Mullen will serve on the Audit Committee and the Operations and Nuclear Oversight Committee. She retired in April as president and chief executive of Insight Enterprises, a technology services firm that supports business, government and educational institutions. Prior to Insight, Mullen spent 21 years at Dell Technologies in supply chain, delivery and logistics roles, and held leadership positions at Cummins Engine Co. She also currently serves on the board of The Toro Co. In a statement, Harry Sideris, president and chief executive of Duke Energy, said Mullen’s experience as a transformative leader will help the company accelerate its vision for the future of energy. Ted Craver, independent chair of Duke’s board, said the company is pleased to add a proven executive with expertise in AI, digital innovation and customer-focused execution. Duke Energy serves approximately 8.7 million customers across the South, with operations in Indiana, Ohio and Florida, where about 2 million customers reside. The company also provides natural gas service.