Depending on its chemical-physical properties, biomass can be converted into useable forms of energy, such as thermal/electric energy or fuels for the transportation sector. The main technologies used for the conversion are based on thermochemical processes, biochemical/biological treatments, or mechanical extraction of oils. Obviously, the conversion process influences the eventual needed pre-treatments as well as the available final energy.
In the European Union, energy from biomass (bioenergy) is the main source of renewable energy, with a share of almost 60% that is expected to further increase, especially in the sectors of electricity and transport biofuels. However, the increase in the biomass demand for energy generation causes concern for several problems, such as land-use competition, deforestation, crops for food vs. biofuels, use of food, and water systems. These issues can be addressed by using residual biomass for energy generation.
For this reason, assessing the available energy potential from residual biomass and the best route for its recovery considering energy, environmental and economic analyses is becoming more and more attractive. Indeed, compared to other renewables, due to the quite mature technological level, low economic costs, high availability and easy accessibility residual biomass may be a sustainable and reliable energy source.