Energy efficiency standards for residential and commercial equipment have been a major source of energy conservation in the US This study estimated key national impacts of potential new and upgraded energy efficiency standards. These impacts approximate the opportunity for national benefits that may be lost if energy efficiency standards for residential and commercial equipment are not upgraded and expanded from current levels. The results suggest that national benefits from new and upgraded standards may be substantial. They also indicate that standards for currently unregulated products may yield more benefits than upgrading minimum efficiency standards for products that already have them. The majority of those currently unregulated products are in the commercial sector. Published by Elsevier Ltd.