The employment of fossil fuels is spread in a wide range of different sectors, such as the residential and the industrial ones, including the transportation as well, not only to generate power but also to generate heat or cold. This high dependency covers many aspects of the modern world in such a deep way that the exploitation of fossil sources has become huge. Nevertheless, it is well known that the combustion of fossil fuels gives as byproduct the emission of CO2 which in turn is reckoned to be the main cause of global warming. The climate has been submitted to more changes in the last few decades than during the whole life of the planet, with huge consequences for the environment.