Lignocellulosic biomass makes up the main part of the biomass produced in the world (12.1011 ton per year); relatively speaking, saccharose and starch make up a lower part (108t). Wood (from secondary-growth species) and related biomaterial from primarygrowth species (palms, coconut, bamboo) make up nearly 80% of lignocellulosic biomass produced in the world. The remaining part mainly comes from co-products of food plants (straw and co-products from cereals and oleaginous plants, bagasse...) and also annual plants produced for fibre (cotton, flax, hemp). A part of these fibres is used for other various applications than energy: pulp, biomaterial, and bioproducts. The wide range of celluloses- lignin-hemicelluloses distribution and structure of these biopolymers sometimes limit their applications. The development of these applications is also limited by two factors: (1) the collection and the transport of the fibres are not well organized; (2) the fibres must be frequently left on the ground after harvesting in order to maintain the soil fertility. Lignocellulosic materials play a major role to save fossil fuels for three main reasons: (1) their elaboration and their use need a low quantity of energy, by comparison with other materials; (2) lignocellulosic materials capture carbon during plant growth and store it during the life cycle of the manufactured products; (3) savings of energy are also possible when the biomaterials are used on the spot instead of imported materials, without long transport distances. It is economically interesting to produce energy from lignocellulosic biomass only if a part of this biomass is used as far as possible for higher added value applications, i.e. plant materials. Co-products and by-products used for energy are then obtained at lower cost. Lignocellulosic materials and energy applications are directly linked due to carbon storage in biomass that is used for energy at the end of life cycle.