The main goal is the evaluation of biomass as renewable resource in Catalonia. Its scope requires the study of different subjects, developed in the twelve chapters that compose the document. The Chapter 1 describes the goals of the PhD thesis. The Chapter 2 describes the reasons that justify the energetic use of biomass. The Chapter 3 shows the general methodology used. The Chapter 4 carries out a multicriterion analysis of energetic valorisation of forestry biomass. The Chapter 5 quantifies the available biomass for energy production in Catalonia. The Chapters 6, 7, 8 and 9 analyze the technologies and the feasibility of power generation using rapeseed and poplar energy crops. The Chapter 10 characterizes physical-chemically the rapeseed biomass as complementary fuel to the current use of the grain for bio-diesel production. The Chapter 11 evaluates the potential use of other crops for chemicals production. The Chapter 12 summarizes the Main Conclusions.