The U.S. Energy Information Administration‘s Commercial Buildings Energy Consumption Survey (CBECS) is the only nationally representative source of statistical information on energy-related characteristics, consumption, and expenditures for the nation’s 5.6 million commercial buildings totaling 87 billion square feet of floor space. Building characteristics information from the 2012 survey is being released in stages through the spring, and consumption and expenditures data will follow later in the year.
The CBECS survey process spans four years, beginning with development of the sample frame and survey questionnaire and ending with release of data to the public. The 2012 CBECS was the tenth survey in the series since 1979. A whole building, as opposed to an individual business or establishment, is the basic unit of analysis for CBECS because the building is the energy-consuming unit. In order to select a statistically valid sample of buildings that will produce accurate information about the commercial buildings population, EIA needs a frame, or list of commercial buildings, from which to select a sample.
Currently there is no existing comprehensive sampling frame of U.S. commercial buildings, so EIA must construct a frame. Most of this frame is called the area frame portion; it comprises all commercial buildings in statistically selected geographic areas. Trained field staff walk or drive through these selected areas and record information about every commercial building.
The other part of the frame (as much as 20%) is called the list frames portion and is constructed from five lists of large buildings, such as hospitals, airports, and federal government buildings, obtained from both public and private sources. This multiframe approach ensures that all types and sizes of commercial buildings have a chance of selection.
Frame accuracy is critical for the CBECS because, unlike the Residential Energy Consumption Survey, which can benchmark results to housing unit estimates from U.S. Census Bureau surveys such as the American Community Survey and the American Housing Survey, the commercial building population totals that come from CBECS are the benchmark—there are no similarly comprehensive surveys for comparison.