HOUSTON–(BUSINESS WIRE)–Calpine Corporation (Calpine), America’s premier privately held competitive power company, published its first-ever sustainability report today. The report highlights Calpine’s performance through an environmental, social and governance (ESG) lens, examining the company’s state-of-the-art portfolio of clean, flexible, and reliable power plants and renewable generation. Today, Calpine is the nation’s largest generator of electricity from natural gas and geothermal resou