The ENERGY STAR national Energy Performance Rating and Certification system was designed to facilitate comparisons of the energy performance of commercial buildings, and recognize the most efficient and cost-effective buildings in the country. This program attempts to affect both the design and operation of buildings by providing a rating system to measure energy performance, establishing a national goal for energy efficiency, and recognizing achievement through a highly regarded certification mark. By providing a simple, but effective metric to evaluate and communicate building energy performance, ENERGY STAR strives to facilitate understanding and communication between building owners, occupants, lenders, appraisers and the energy products and services community to pursue mutually beneficial, cost effective solutions to improve the energy efficiency and indoor environmental performance of commercial buildings.
The ENERGY STAR Labeled Buildings by definition serve as contemporaneous examples of commercial buildings that have achieved exemplary energy performance, while maintaining occupant comfort and cost competitiveness. As such, they offer an invaluable opportunity to study the design, technological, and operational characteristics that contribute to these accomplishments. Having established a basic understanding of the ENERGY STAR performance rating system, the objective of this paper will be to explore the similarities and differences of these buildings compared to their peers, and attempt to identify common ingredients or attributes of high performing buildings. This paper will present data on the measured energy performance, physical and operational characteristics of the 475 ENERGY STAR offices buildings certified through 2001, and compare them relative to the existing commercial buildings market. As the largest case study of whole-building energy performance, the information obtained from this unbiased assemblage of buildings provides a unique learning experience for all businesses interested in developing energy-efficiency projects in commercial buildings.