United Nations Educational, Scientific and Cultural Organization (United Nations Educational, Scientific and Cultural Organization).

There are other units used in the energy field which are not recognized by either the CIPM or ISO. We will only refer to them for information.

Nº of organizations of workers legally constituted with the objective of defending their rights.

The unit of atomic mass is an arbitrary unit that defines the mass of individual atoms. The standard is equal to the fraction 1/12 of the mass of a carbon atom 12. 1 u = 1, 660 540 x 10 -27 kg.

There are certain units which, although not part of the SI, are recognized by the International Committee on Weights and Measures (CIPM) as having to be considered for their practical importance.

Natural or artificial structure intended to evacuate excess flow.

At a given date, estimated quantities that the analysis of geological and technical data indicate as being economically recoverable from already discovered deposits, with a sufficient degree of probability to suggest their existence. Due to the impossibility of predicting when and to what extent the recovery of such reserves will be possible in the future, the assessments must correspond to a set of values, but may be given by a single intermediate value that considers all uncertainties. Unproven reserves can also be classified as probable reserves or possible reserves.

Raw coal stock at which the amount of waste is removed as well as the losses occurring during extraction, transport and treatment.

Ratio between the time of and the duration of the reference period.

Hydraulic utilization with several associated objectives, among which are the production of electricity, flood regulation, protection against floods, water supply for populations and for irrigation, river navigation, recreational purposes, etc.

Volume of water available in a reservoir between the full storage level and the minimum level of normal operation.

Energy available to the consumer after the last conversion on his own equipment.

Balance established on the basis of an accounting of the different energy flows according to their actual calorific value, from the primary supply to the useful energy recovered by the final consumer from the output of their appliances and thus showing the losses recorded at the different stages of processing and consumption . As there is no effective measure of useful energy, this balance sheet is in fact a balance sheet derived from the final energy balance, with average or estimated yields being used for transformation by the last apparatus, which presupposes a good knowledge of the park and the incomes , which can vary in important proportions.
Note: It is possible to determine the useful energy according to the technical processes, uses or economic sectors, but these aspects present theoretical and practical difficulties such that, at present, the above method is generally applied . (A) The conversion factor (sometimes called the conversion coefficient) means the exact conversion ratio of a unit of a system into a unit of another system: inch by meter, gallon (to be precise) in cubic meter, etc. ; (B) the coefficient of equivalence makes it possible to assess, in a single unit (see unit of energy account), quantities of energy of different natures or, where appropriate, associated with different uses.

Electric power at the exit of the plant.

Concept that establishes the quantity of high quality coal and of poor quality coal considering the ash and water content.
Note: Different calculation procedures are used depending on the countries and the extraction zones.

Part of the total flow which, after the mandatory water deductions laid down in the specifications and the inevitable losses, is available for the purposes of recovery.

Electrical power output from the plant.

Part of the energy spectrum containing waves that escaped the influence of the wind that created them. As the wave is usually created from more distant sources, it usually falls in a narrow frequency band of the low frequency zone of the spectrum.

Ratio of total waste of which the method of recovery is identified and total waste sent to final destination. This includes by-products: fly ash and slag of coal and biomass, and gypsum. Waste resulting from the activities of service providers is not included.