METHODOLOGICAL DESCRIPTION (a) Underlying Definitions and Concepts: Energy use per unit of value added is one
way of measuring energy requirements per unit of output in the agricultural sector.
While energy use per unit of physical output is a better indicator of energy efficiency
in specific agricultural processes, data supporting this level of disaggregation are
rarely available. Measuring intensity in terms of economic output is useful for
aggregating and comparing energy developments across the entire economy. Total
energy use in agriculture derives from the energy inputs at all the stages of
agricultural production and processing. The agricultural activities include land
preparation, mechanization, fertilization, irrigation, harvesting, transport, processing
and storage. Each of these stages uses different forms of energy (mechanical,
electrical, thermal), which can be aggregated in equivalent units.
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. Annex 3 includes a decomposition method for energy
intensities.
(b) Measuring Methods: Energy Use: Annual energy inputs for each stage of agricultural production and
processing are determined and converted into equivalent units and aggregated as total
energy. Energy use is usually measured at the point of consumption (i.e. the farm),
and ‘own energy’ (including internal use, biomass, etc.) should be added to the
purchased energy.
Units: toe for final energy and kWh for electricity.
Output: Net economic output is measured in agricultural value added (International
Standard Industrial Classification [ISIC], Division A). The sector comprises crops and
livestock production, agricultural services, and forestry and fishing/hunting/trapping.
Data on physical output of some products are available from the Food and Agriculture
Organization of the United Nations (FAO). However, matching energy-use data for
the same products are rarely available, and thus it is difficult to construct
disaggregated energy intensities from the physical output data.
Unit: Constant currency. The market value of output in the real national currency is
deflated to a base year using GDP deflators. The national currency can be converted
into US dollars, using purchasing power parity for the base year.