Renewable energy sources represent high potentials in reducing the dependency from fossil fuels. Such sources can be inserted into different ‘energy families’, as the solar one - thermal and photovoltaic - hydroelectric, wind farms, geothermic and from biomasses. These latter are characterized by being organic elements from vegetal and animal sources not used by humans neither as food nor as raw industrial materials (Favretto & Santoprete, 1994), although sometimes also maize is used as organic matter to produce biogas, even if maize could also be used as food.
Vegetal biomasses represent the most refined means of collection of solar energy as vegetal plants by means of chlorophyll photosynthesis convert the energy radiated by Sun into chemical energy with high potential. In such sense biomasses are considered as renewable and long-lasting resources, limited only by the respect of their regeneration pace. Furthermore biomasses are considered neutral in terms of the CO2 emissions in the atmosphere.