Environment point of view: in nature it is proved that wood, when it has made the complete decomposition cycle, releases in the atmosphere a quantity of CO2 (carbon dioxide) that is then used for the growth and development of new plants. Economic point of view: 2,3 Kg of dried wood have a calorific power equal to 1 lt of diesel oil or 1 m3 of natural gas. Taking into consideration the equality of benefits it is only the cost that changes and that is lower of the 50-60% for the purchase of wood in comparison to other fuels.