Energy Efficiency and Greenhouse Gas Limits for Existing Power Plants: Learning from EPA Precedent

Section 111(d) of the Clean Air Act will soon require the EPA and state governments to regulate carbon dioxide emissions from existing fossil fuel–fired power plants. Many stakeholders envision a role for end-use energy efficiency as a flexible compliance strategy under Section 111(d), and though energy efficiency measures have no precedent under the section, there is a long history of Clean Air Act programs that recognize energy efficiency as viable emission reduction strategy. This joint analysis by the Nicholas Institute for Environmental Policy Solutions and the American Council for an Energy-Efficient Economy identifies key issues with crediting end-use energy efficiency measures for Section 111(d) compliance—estimating which units experience emission reductions, measuring energy savings, and quantifying reductions in CO2 emissions. The report then explores how the incorporation of energy efficiency into the National Ambient Air Quality Standards program, the NOx SIP Call, and other Clean Air Act programs, can inform federal and state environmental regulators as they evaluate these Section 111(d) issues.