U.S. Energy Secretary Ernest Moniz, in the area for a U.S. Department of Energy public hearing and to speak at Iowa State University’s commencement, told a Des Moines audience he is impressed by the long service of Gov. Terry Branstad at the Statehouse and of former Gov. Tom Vilsack as U.S. agriculture secretary. “I find it hard to comprehend 21 years and running as governor,” he told Branstad at the State Historical Building in Des Moines. “I guess Secretary Vilsack kept your seat warm between terms. Now he is moving toward eight years in the Cabinet, which I guess is another tribute to the persistence of Iowans.” Also on the panel: Frank Cownie, the longest serving mayor in Des Moines.