On January 17, 2007, Senator Feinstein (D-CA) and Senator Carper (D-DE) introduced S.317. This bill would establish a traditional cap and trade program-i.e., with compliance required at the smokestack-for the electric generating sector.

Affected sources-those that are reuiqred to surrender allowances on an annual basis-are defined as electric generating facilities with a nameplate capacity of greater than 25 megawatts that combust "greenhouse gas emitting fuels," and generate electricity for sale. The bill also includes cogeneration facilities-which supply more than 1/3 of their potential electric output to the grid-within the definition of an affected source.