Break out the black roses and the "over the hill" birthday cards. Progress Energy's Bartow power plant is turning 50. But it's still got plenty of juice left. The power plant is nearly done with a $795-million makeover that will increase the power it puts out, make the switch from oil to natural gas and reduce emissions. David Sorrick, vice president of power generation for Progress Energy Florida, said, "When the work is completed, this 50-year-old workhorse of a power plant will be a state-of-the-art powerhouse." Community leaders have been invited to a 50th anniversary celebration from 11 a.m. to 1:30 p.m. Thursday at 1600 Weedon Island Drive.