Energy Star Rating System
The US Environmental Protection Agency defines the rating system: “The national energy performance rating is a type of external benchmark that helps energy managers assess how efficiently their buildings use energy, relative to similar buildings nationwide. The rating system’s 1–100 scale allows everyone to quickly understand how a building is performing — a rating of 50 indicates average energy performance, while a rating of 75 or better indicates top performance.”
Performance rating uses basic information about the building such as its location, size, and number of occupants to estimate energy use under three scenarios: “if it were the best performing, the worst performing, and every level in between. The system then compares the actual energy data (…) entered to the estimate to determine where (the) building ranks relative to its peers”. Only top performing buildings are recognized with Energy Star.
To obtain more information on the Energy Star program, please follow attached link http://www.energystar.gov/index.cfm?c=evaluate_performance.pt_neprs_learn.
For detailed information on performance scale, please visit: http://www.energystar.gov/ia/business/evaluate_performance/The_ENERGY_STAR_Energy_Performance_Scale_3.28.11_abbrev.pdf