Where does energy come from?
Every day the Earth receives enough solar energy to satisfy the global energy need. Unfortunately we cannot exploit all this energy. The energy choice of a country is a difficult problem, as it is necessary to consider economic, environmental and technological aspects.
The use of primary sources depends on the characteristics of the territory (for example Iceland is a volcanic island, therefore rich in geothermal sources), on the availability of renewable sources (for example Denmark, which is a windy land, exploits wind energy), or on political or economic decisions (for example the gas pipe that arrives from North Africa favoured the use of methane in Italy, while France, which does not have much energy in its territory, has decided to invest in the construction of nuclear plants).