Table Of Contents

    Biomass cofiring refers to the simultaneous combustion of a biomass fuel and a base fuel to produce energy, usually electrical power. The most common base fuel is coal. The most common sources of biomass fuel include low-value wood from forestry activities, crop residues, construction debris, municipal waste, storm debris, and dedicated energy crops, such as switchgrass, willow, and hybrid poplar. Most biomass feedstocks must undergo significant processing before they can be utilized for cofiring. The shape, size, and moisture-content of feedstock particles need to be adjusted to meet specifications.

    Once the feedstocks are prepared, cofiring is a relatively simple process. A mixture of coal and biomass (typically containing less than 20 percent biomass by energy content) is fed into a modified coal-burning power plant to produce energy. Cofiring systems can be broadly classified as blended delivery systems, in which the two fuels are blended prior to injection, or separate feed systems, in which they are injected into the system separately. The former requires less modification to the power plant, although modifications are generally simple for both approaches. Additional modifications to the fuel-handling, processing, and storage systems may be necessary.

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