Deference to state authorities and regional compliance strategies have been suggested by
observers with regard to EPA’s deliberations over GHG reduction for existing CFPPs. State public utilities commissions (or similar entities) often require utilities to conduct book depreciation
studies (either in connection with rate cases or independent of rate cases). Such studies commonly
examine the physical condition of power plants, and the utility’s recovery of its investment in electric plant. Federal legislation could tie incentives for efficiency improvements to such studies and direct states to meet individual or regional goals for GHG reduction.