An Energy Efficiency Resource Standard (EERS) is a flexible mechanism to ensure that utilities adopt energy efficiency as a clean, cost-effective energy resource. A federal EERS would require that electricity and natural gas utilities help their customers reduce energy use by a specified and increasing amount each year, based on a percentage of total energy sales. It complements a renewable electricity standard (RES), which requires that a percentage of electricity generation be from renewable sources. EERS is a tested policy measure that has successfully reduced energy use in several states. A national EERS would lower energy costs, reduce air pollution and global warming, create jobs, and improve energy reliability throughout the nation.