Renewable sources of energy are those sources which are not finite and which are present in nature as a result of natural processes.
These sources are associated with water, air, the sun, the earth heat, etc. Examples of these include:
Water: hydro-electric, small hydro-electric, tidal, swell.
Sun: photovoltaic solar, thermal solar, bio-mass.
- Earth heat: geothermal
RENEWABLE ENERGIES FEATURES
In the first place, we are speaking about endless sources.
Secondly, the use of these sources is exempt of carbon dioxide CO2 net emissions, main gas associated with the greenhouse effect.
In the third place, by their own nature, renewable energies are always used on a local basis, which avoids the creation of major infrastructures, related to fuel supply and connection of the facilities to the main network. This also means that the impact and benefits remain mainly at the local level.
In the fourth place and due to the aforementioned, renewable energies are a political target both at European and national or regional levels. Political support of their promotion comes from the determined will of all government levels, translated into a number of measures to that effect.
Finally, and most importantly: due to all the above, renewable energies have a legal framework which confirms their positive effects and aims at the real achievement of their growing participation in the satisfaction of energy requirements in the medium term. That makes renewable energy projects profitable, a safe investment with a high return, since their benefits are guaranteed. In Spain, this kind of projects are governed by the Royal Decree 436/2004 which sets out the methodology for the updating and organization of the legal and economic system of the activity of electric energy production, as a special regime.