Short rotation coppice for bioenergy: From biomass characterization to establishment A - review

The co-firing of biomass with coal in power plants is an important way to reduce greenhouse gas (GHG) emissions and energy dependency and to ensure security of energy supply. The development of energy cultivations, namely the implementation of wood short rotation coppice (SRC) cultivations can represent an energy and environmental sustainable solution to provide biomass to the power plants and can foster the economic development of the regions where these cultivations will be implemented. A full knowledge of the combustion behaviour of the biomass is needed to optimize the co-firing process of biomass with coal. In this sense, it is important to critically review the relevant studies on the kinetics of the combustion and/or pyrolysis of woody biomass from SRC cultivations. Moreover, it is also important to critically assess the economic and technical feasibility of the implementation of wood SRC cultivations to produce bioenergy. These represent the two main objectives of this manuscript. The review revealed that data from two main experimental techniques are used to estimate the kinetic parameters of biomass combustion and pyrolysis - thermogravimetric analysis and drop tube furnaces. It can be also concluded that different methods can be used to estimate the kinetic parameters from these experimental data, namely model-fitting and model-free methods. Additionally, the review showed that the kinetic parameters depend on the biomass characteristics, on the experimental technique and on the method applied. In regard to wood SRC cultivations for bioenergy, it is concluded that they have a positive net energy, contribute to the reduction of GHG emissions, but its financial viability depends on subsidies or grants.