ECO5: Resources-to-production ratio Brief Definition Ratio of the energy resources remaining at the end
of a year to the production of energy in that year
Also, lifetime of proven energy resources
Units years
Alternative Definitions Total resources
Depletion rate of resources
Agenda 21 Chapter 4: Consumption and production patterns
POLICY RELEVANCE (a) Purpose: The purpose of this indicator is to measure the availability of national
energy resources with respect to corresponding fuel production. Resources are
generally defined as concentrations of naturally occurring solid, liquid or gaseous
material in or on the Earth’s crust in a form that makes economic extraction
potentially feasible. Total resources include reserves, and hypothetical and speculative
undiscovered resources. This indicator considers fuels such as oil, natural gas, coal
and uranium. It provides a relative measure of the length of time that resources would
last if production were to continue at current levels.
(b) Relevance to Sustainable Development: The availability and security of energy
fuel supplies are key aspects of sustainability. This indicator provides a basis for
assessing possible future energy supplies with respect to the current availability of
energy resources and levels of production. The proper management of energy
resources is a necessary component of national sustainable energy programmes.
(c) International Conventions and Agreements: None.
(d) International Targets/Recommended Standards: None.
(e) Linkages to Other Indicators: This indicator is linked to indicators of annual
energy production, annual energy use, imports, prices and reserves.
METHODOLOGICAL DESCRIPTION (a) Underlying Definitions and Concepts: Resources include reserves, estimated
additional resources and speculative resources. Proven reserves indicate the resources
in place that have been assessed as exploitable under present and expected economic
conditions with available technology. Estimated additional resources are resources
inferred to exist. Speculative resources are resources thought to exist, mostly on the
basis of indirect evidence and geological extrapolations.
