Energy efficiency is a vital part of the nation's energy strategy and has been since the first oil crisis in 1973. As part of a national priority for improving energy efficiency, the Department of Energy's (DOE) Office of Energy Efficiency and Renewable Energy (EERE) has established a national system of indicators to track changes in the energy intensity of our economy and economic sectors over time.
This system of energy intensity indicators can do the following:
- Show how the intensity of energy use and its components are changing
- Help raise public awareness about how and why energy intensity has changed over the years
- Complement other provided inputs to policy and program analyses, including improved understanding of the impact of program and policy choices on energy intensity
- Improve understanding of the role of efficiency improvements in changing energy markets
The purpose of this site is to provide the public with information on energy intensity indicators that can be used to consistently track changes in U.S. energy intensity over time, for the entire economy as well as for specific end-use sectors – the four end-use sectors (transportation, industrial, residential, and commercial) and electricity generation (see Highlights).
The current edition of the system of energy intensity indicators provides:
- Indexes of energy intensity from 1970 to 2011 that reflect changes in the efficiency of energy use, as feasible with currently available data
- Energy intensity, energy use, and activity measures at the economywide level, sector level (transportation, industrial, residential buildings, and commercial buildings), and at even more disaggregated levels, where data permit
- Downloadable spreadsheets with detailed data and energy intensity indexes for each major end-use sector and associated subsectors
Overview of Methods
The system of energy intensity indicators developed by DOE is based upon a hierarchical framework that begins with detailed indexes of energy intensity for various sectors of the economy, which are ultimately aggregated to an overall energy intensity index for the economy as a whole. The definitions of energy used in the system depend upon how the transmission and generation losses associated with the use of electricity by various sectors are treated. Finally, the system recognizes that at an aggregate level the conventional measures of energy intensity are not all traceable to improvements in energy efficiency. Many of these other "structural" factors influencing overall energy consumption are explicitly captured in the system developed here. These elements are discussed in summary fashion here.
Figure E1 illustrates the nature of the energy intensity indicators, in this instance for the U.S. economy as a whole. The figure compares the economywide energy intensity index, derived in the "bottom-up" (hierarchical) fashion from more detailed data, with an index derived from the ratio of total energy use to aggregate gross domestic product (GDP). Click on the figure to learn more about its construction as well other highlights related to overall energy use and energy intensity in the U.S.