Sum of operating time with passive availability time.

Balance key point which should balance, for the reference period, the internal consumption of the geographical entity concerned.

Difference in level between centers of gravity of useful volumes of upper and lower reservoirs.

Degree of reflection that is measured for a coal grain oriented in any way on a polished surface and in non-polarized light.

Technical indicator of quality of service. Quotient of the sum of the durations of the interruptions at the delivery points, during a given period, by the total number of delivery points, during the same period.

The denomination bar can be attributed to the decimal multiple equivalent to one hundred thousand pascals (100 kPa). The bar should only be used for the measurement of relative pressures with the aid of pressure gauges.

The barn is the unit used in nuclear physics to express effective sections. 1 b = 10 -28 m 2 .

Volume unit, based on the volume of a barrel, used in the petroleum industry and equal to 0, 158 91 m [in the case of a barrel of crude oil at 60ºF (15ºC) under normal conditions].

Central used mainly to cover the base of the load diagram.

Constant part of the load of a consumer appliance or a network over a specified period (eg day, month, year).

Unit of activity of a radioactive source. Becquerel is the activity of a quantity of radioactive nuclide for which the number of spontaneous nuclear transitions per second is equal to 1. 1 Bq = 1 s -1 < / Sup>

Geological formation rich in coal. It is generally comprised of substantially parallel engaging land surfaces.

The level of the bed is the particularity of the terrain, finding the fine granulometry of the layer between two stony layers of coarse grain. Note: A given lode can be represented locally by a lode level.

Unit for base logarithmic quantities 10. For example, the sound power level is L p = lg (P / P 0 ) B, where P 0 < / Sub> reference power. 1 B is the field amplitude level when 2 lg (F / F 0 ) = 1 or is the power level when lg (P / P0) = 1 (where F 0 < / Sub> and P 0 are reference values). Usually the submultipled decibel is used instead of bel, with 1 dB = 0.1.

Ratio between the power developed by a turbine and the maximum theoretical power available, calculated according to Betz's law (see Betz's Law).

For an ideal turbine having a passing surface A, the maximum theoretical power developed for an undisturbed wind velocity V 8 (see Isovento) is equal to 8/27 8 Sub> 3 AV being The density of the air. Note: The available P L kinetic power in an air stream is P L = 1/2 AV 8 3 . It is often considered a C p factor (or yield) As the ratio of the net power P P L (theoretical power available), that is, C p = P / p equals 16/27. Note 2 Betz's law is an approximation in wind power plant calculation because the density of air is considered constant when passing through the rotor.

Revenue from activities resulting from the application of measures to improve energy efficiency.

Properties of certain coals which at a certain temperature acquire a pasty and binder state. Volatiles, when released from the mass, cause it to become pasty, turning into coke by cooling. The greater the plasticity due to heating, the greater the binder properties of the coal. Coals that, on combustion, leave a fine grain residue are not binders.

Transformation of solar energy into biomass through a biological process and, by extension, transformation of biomass in order to obtain usable energy.