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The aim of this work is to provide a wide database of kinetic data for the most common biomass by thermogravimetric analysis (TGA) and differential thermogravimetry (DTG). Due to the characteristic parameters of DTG curves, a two-stage reaction model is proposed and the kinetic parameters obtained from model-based methods with energy activation values for first and second stages in the range 1.75·10(4)-1.55·10(5)J/mol and 1.62·10(4)-2.37·10(5)J/mol, respectively. However, it has been found that Flynn-Wall-Ozawa and Kissinger-Akahira-Sunose model-free methods are not suitable to determine the kinetic parameters of biomass combustion since the assumptions of these two methods were not accomplished in the full range of the combustion process.

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Three types of forest stands (chestnut coppice, maritime pine stands, and poplar and willow short-rotation woody crops (SRWC)) were evaluated to determine their potential for energy production. The properties of the main aboveground biomass fractions (wood, bark and crown) and also the whole tree were analysed, thus providing data that could be used for management purposes and for evaluating potential forest, biomass energy yields and atmospheric emissions. Proximate, elemental and energetic analyses of the biomass provided important information for evaluating the fuel potential. The energetic value of the biomass derived from the maritime pine stands was higher than that of the poplar and willow clonal stands and chestnut coppice stands. The high ash content of the chestnut bark, relative to that of the wood and crown material, is also an important consideration in relation to energy production. The proportion of carbon concentration accumulated per tree was very similar in all types of material studied, although the N and S contents were higher in the maritime pine stands than in the other stands. For this reason, selection of species and fractions can help to improve fuel quality and the efficiency of the combustion processes, and to minimize atmospheric emissions.