Development of Renewable Energies in some European countries, Achievement of the 2020 objective

Abstract

Renewable energies are those ones which can be obtained from natural sources virtually inexhausti-ble; some of them because of the huge amount of energy they contain, other ones because of they are able to regenerate by natural means. Its environmental impact is zero in the emission of green-house gases such as CO2. Solar, wind, geothermal, hydraulic and electrical energies are considered renewable energies. Biomass and tidal energy also may be included in this group. An alternative energy (or, more precise, an alternative source of energy) is one that can replace en-ergies or current energetic sources, either by their lower polluting effect or primarily for their ability to renewal.