An Energy Efficiency Resource Standard (EERS) is a market-based mechanism to encourage more efficient generation, transmission, and use of electricity and natural gas. State public utility commissions or other regulatory bodies set electric and/or gas energy savings targets for utilities, often with flexibility to achieve the target through a market-based trading system. All EERS’s include end-use energy savings improvements. In some cases, distribution system efficiency improvements and combined heat and power (CHP) systems and other high-efficiency distributed generation systems are also included.