Biomass is used for facility heating, electric power generation, and combined heat and power. The term biomass encompasses a large variety of materials, including wood from various sources, agricultural residues, and animal and human waste. Biomass can be converted into electric power through several methods. The most common is direct combustion of biomass material, such as agricultural waste or woody materials. Biomass combustion is a carbon-free process because the resulting CO2 was previously captured by the plants being combusted. Widely-applied technology options are available for biomass-based power generation, including: - Co-firing: Biomass co-firing in modern, largescale coal power plants is efficient, cost-effective and requires moderate additional investment. In the case of cocombustion of up to 5%-10% of biomass (in energy terms) only minor changes in the handling equipment are needed and the boiler is not noticeably derated. For biomass exceeding 10% or if biomass and coal are burned separately, then changes in mills, burners and dryers are needed. - Combustion in dedicated power and CHP plants: Biomass can be burned to produce electricity and CHP via a steam turbine in dedicated power plants. The typical size of these plants is ten times smaller (from 1 to100 MW) than coal-fired plants because of the scarce availability of local feedstock and the high transportation cost. Biomass-fired power and CHP plants can be characterised by the boiler technology (i.e. Water-cooled vibrating grate (VG) boilers; bubbling fluidised bed combustion (BFBC) boilers; circulating fluidised bed combustion (CFBC) boilers. Biomass availability is key for bioenergy. Biomass-based power and CHP are widely used in regions that have ample wood resources, forestry or agricultural residues.Biomass use for CHP may be in competition with other, non-energy uses of agricultural and forestry residues or woody industrial waste (i.e., pulp and paper). Increasing competition between different uses may increase the price of biomass. Biomass market stability is a critical issue. Sustainability, environmental and social aspects (i.e., GHG reductions, food security, biodiversity, impact on soil and water) could, if not properly addressed, present significant barriers to biomass use.