Non-renewable primary energy consumption
Introduction
A source of primary energy is any form of energy available in nature before being converted or transformed. It consists of the energy contained in crude fuels, solar energy, wind energy, geothermal energy and other forms of energy that constitute an input to the system. If it is not usable directly, it must be transformed into a secondary energy source (electricity, heat, etc.).[1].
In the energy industry, different stages are distinguished: the production of primary energy, its storage and transportation in the form of secondary energy, and its consumption as final energy.
Thus, for example, the mechanical energy of a waterfall is transformed into electricity and when it reaches the end user it can be used for different uses (lighting, production of cold and heat, etc.). At the user level, all forms of energy are, therefore, substitutable. This series of transformations involves a specific energy chain, such as the one that occurs in the oil chain: extraction, transportation, refining and distribution. Each transformation is characterized by its performance "Yield (physics)"), always less than 1 due to the losses inherent to the process.
The concept is especially used in energy statistics ("in the course of compiling energy balances"). However, primary energy is usually identified as the energy that results from the first transformation (such as nuclear heat, wind or hydraulic electricity) and final energy is the energy that finally reaches the user (at the meter) since these are the ones for which data is available.
Definitions
ECLAC, in the document "Energy sustainability in Latin America and the Caribbean: The contribution of renewable sources"[2] defines Primary Energy as:.
A distinction must be made between potential availability and effective availability. Thus, for example, a certain hydrographic basin has, due to its physical characteristics and the rainfall over it, a certain hydroelectric potential, but if a hydroelectric plant is not built, that energy cannot be used.
Considering hydroelectricity as primary energy is a convention, since in reality what is available in a hydroelectric plant is mechanical energy that is transformed into electricity through a physical modification. The same can be said of nuclear energy, in which radioactive materials produce heat that is then transformed into electricity by turbines and generators, through physical processes such as the evaporation of water.