Biomass

Abstract

The energy stored in the biomass existing on the Earth can be transformed by chemical or biological processes into heat or electricity. From a certain point of view, biomass can be considered as solar energy stored in carbohydrate chemical bonds by means of the photosynthesis process. Therefore, the emitted CO₂ to the atmosphere, when biomass is burned or transformed, can be considered to be equal to the CO₂ absorbed during its previous growth, i.e., energy from biomass could in principle be considered as carbon neutral. It is important to remark that bioenergy provides about 12 % of the global energy consumption, and therefore is, together with hydropower, one of the main renewable energy resources in the world. In this chapter, we describe some of the most common energy processes for using biomass as a fuel: direct combustion, pyrolysis for the production of charcoal, gasification for obtaining synthesis or producer gas, co-firing with coal, etc. On the other hand, the production of liquid or gaseous biofuels will be treated in Chap. 4.