The candela is the luminous intensity, in a given direction, of a source emitting a monochromatic radiation of frequency 540 x 10 12 Hz and whose intensity in that direction is 1/683 W × sr -1 . [16th CGPM (1979), Resolution 3].

Amount of electric power that could be produced in its own power plant and in the entire downstream cascade by completely emptying its "useful capacity" without counting on other possible flows.

Electrical energy that can be produced starting from the upper reservoir initially full.

Mobile conveyor belt over bolts. Itis generally used as a connecting link between the excavator and the conveyor belt.

Quantity of CO 2 emitted per unit of energy produced.

Degree of relative value for the economy of the exploitation of a deposit or part of a deposit. The classification of the exploitable, conditionally exploitable deposits and of the non-exploitable deposits is guided by the current valuation conditions. The classification criteria shall be indicated.

A process whereby the initially deposited plant materials are converted into coal from lignite peat.
Note: The process is characterized by a relative increase of carbon content and a reduction of water and oxygen content. As carbonization increases, the volatile content decreases.

Heating of raw organic material in absence of air to obtain coke, crude gas and crude tar (see Liquid and gaseous fuels).

Implosion of water vapor bubbles, usually of very small dimensions and contained in the liquid vein. These bubbles form when the local pressure becomes lower than that of the saturated vapor and they change from the gaseous state to the liquid whenever the pressure again exceeds the saturated vapor pressure.
Note: Cavitation can cause significant damage to the material which necessitates repairs such as welding, which is why precautions must be taken at the time of turbine construction to reduce it to an acceptable value.

Company of Development and Infrastructures of Alqueva, SA.

Mechanism established by the Kyoto Protocol to allow Annex I countries to finance CO 2 emissions reduction projects in non-Annex I countries, with a counterpart of Receive, in the same proportion, emission reduction certificates, tradable in the market.

Geological layer situated immediately above the lode.

The Celsius temperature is expressed in degrees Celsius which is a special name for the Kelvin unit. 1 ° C = 1K

Installation in which the potential and kinetic energy of water is transformed into electrical energy.

Method of connecting and disconnecting consumer groups, usually by remote control, from the distribution network.

A mechanical machine that moves along the front and which, by means of cutting peaks, inserted in an endless chain, driven by a motor, performs a stroke in the layer (usually, but not always, in its lower part) which Facilitates its start-up.

The machine is preferably used for long-term operation and in which one or two rotating drums provided with cutting blades pull a portion of the carbon fillet and then load it onto the conveyor underneath or at the side of the machine.

Installation designed to cushion the transient pressure oscillations in the hydraulic circuit.