In an action long-awaited by environmental activists and viewed with some trepidation by the business community, on April 13, 2012, EPA published in the Federal Register its proposed greenhouse gas (GHG) emission limits for new power plants (technically, electric utility generating units or EGUs).1 Comments on the proposed rule must be received by EPA no later than June 12, 2012.

The proposed New Source Performance Standards (NSPS) are EPA's first proposed numeric GHG emission limits for any category of industrial facility, and will have a significant impact on the licensing and operation of new power plants when they are issued in final form. EPA's approach to the final standards is also likely to establish precedents for EPA's regulation of GHG emissions from other types of facilities.