E.P.A. and emissions. The Environmental Protection Agency set a new rule limiting carbon dioxide emissions to 1,000 pounds per megawatt hour, which is easily reached by new natural gas powered plants. The thing is that the rule applies only to newly built plants which are gas powered, not the old coal burning plants. Should one feel inclined to build more coal fueled plants there's a thirty year time frame to reach the emissions goal, since lack of technology to make that possible now may suddenly change.