ANNEX 3: A DECOMPOSITION METHOD FOR ENERGY USE INTENSITY INDICATORS 1 Introduction This annex provides an overview of a method that can be used to analyse energy-use
developments in a disaggregated fashion. There are a number of journal publications
that describe this method and related results.
2
The indicators employed to analyse energy use intensity are constructed by combining
energy data with data that describe factors driving consumption in end-use sectors.
From these data, various types of energy intensities can be developed. Energy
intensities are related to the inverse of energy efficiencies, but are not equivalent. The
two are related in that the energy intensity of an activity or productive output
summarizes the relationship between an overall measure of output and the energy
used for a variety of processes towards that end. Each process (e.g. heating, motive
power) involves one or more transformations of energy that can be described in terms
of efficiencies.
Changes in intensities are affected by factors other than energy efficiency; therefore,
analysing intensity trends provides important insights into how energy efficiency and
other factors affect energy use.
The method described here distinguishes among three main components affecting
energy use: activity levels, structure (the mix of activities within a sector) and energy
intensities (energy use per unit of sub-sectoral activity). Depending on the sector,
activity is measured either as value added, passenger-kilometres (km), tonne-km,
population or built area. Structure divides activity further into industry sub-sectors,
transportation modes or measures of residential end-use activity. Table A3.1 gives an
overview of the various measures applied for activity, structure and energy intensities
in each sector; Figure A3.1 illustrates the disaggregation into sectors, sub-sectors and
end uses.
1
The method presented here builds on the analytical framework developed under the International
Energy Agency (IEA) Energy Indicator Project. Key findings of this work are presented in the IEA
publication Oil Crises and Climate Challenges: 30 Years of Energy Use in IEA Countries (IEA
2004).
2
Selected references include the following: Krackeler et al. (1998); Schipper, Murtishaw, et al.
(2001); Schipper, Unander, et al. (2001); Unander et al. (1999); Unander et al. (2004).
