Energy Resource Classification and Definitions
Energy Resource Definitions
Absolute Potential Energy Source
The total amount of energy contained within a natural resource. This is a theoretical concept, as it does not specify what fraction is likely to be transformed into useful energy. It requires technical feasibility and economic viability, meaning extraction costs must remain below market prices. Example: Oil deposits currently considered unattainable.
Resource Appeal
The total amount of an energy source available on Earth. While it possesses an absolute character, it remains subject to uncertainties and may vary as new areas are surveyed.
Energy Reserves
The fraction of a resource that can be recovered using current technology at competitive market costs. This applies specifically to non-renewable sources and fluctuates annually due to technological innovations and market shifts.
- Proved Reserves: Resources that have been discovered and are economically profitable to extract.
- Late Reservations: Includes proven reserves plus estimates of future discoveries.
- Ultimately Recoverable Resources: The sum of final reserves and cumulative production.
Conventional vs. Unconventional Resources
Conventional Appeal: The portion of a resource that is not currently reserved or part of cumulative production, either due to a lack of recovery technology or economic constraints.
Unconventional Coal: Global estimates remain highly uncertain due to a lack of consensus on future recoverability and limited exploration in certain regions.
Non-Conventional Hydrocarbons: Includes various forms of non-classical oil and gas.
Production Metrics
Annual Rate of Production: The total amount of primary energy produced over the course of a single year.