The agency initially proposed that any new power plant emit no more than 1,000 pounds of carbon dioxide per megawatt hour of electricity produced but decided to overhaul that rule this spring out of concern that it would face a stiff legal challenge.
The average U.S. natural gas plant emits 800 to 850 pounds of carbon dioxide per megawatt, and coal plants emit an average of 1,768 pounds. According to those familiar with the new EPA proposal, the agency will keep the carbon limit for large natural gas plants at 1,000 pounds but relax it slightly for smaller gas plants. The standard for coal plants will be as high as 1,300 or 1,400 pounds per megawatt hour, the individuals said Wednesday, but that still means the utilities will have to capture some of the carbon dioxide they emit.
