Updating my analysis from a year ago , despite a more than 100% increase in stock price, I am keeping the rating of independent power producer Vistra Corporation (NYSE: VST ) at “buy,” although just for capitalLaura Starks is the founder and CEO of Starks Energy Economics, LLC (since 2007). She has a degree in chemical engineering and an MBA with a concentration in finance which she has used for many years to invest personally and to share her ideas about energy companies. Her coverage includes utilities, i ...