BIOMASS ENERGY

Biomass Energy

Biological sources provide a wide array of materials that have been and continue to be used as energy sources. Wood, wood wastes, and residue from wood processing industries, sewage or municipal solid waste, cultivated herbaceous and other energy crops, waste from food processing industries, and animal wastes are lumped together by the term biomass. The most compelling argument for the use of biomass technologies is the inherent recycling of carbon by photosynthesis. In addition to the obvious method of burning biomass, conversion to liquid and gaseous fuels is possible, thus expanding the application possibilities. In the context of electric power generation, the role of biomass is expected to be for repowering old units and for use in small (20 to 50 MW) new plants. Several new high-efficiency conversion technologies are either already available or under development for the utilization of biomass.

 technologies and their overall conversion efficiencies

 • FBC (fluidized-bed combustor), 36–38%

• EPS (energy performance system) combustor, 34–36%

• BIG/STIG (biomass-integrated gasifier/steam-injected gas turbine), 38–47%

 Acid or enzymatic hydrolysis, gasification, and aqueous pyrolysis are some of the other technology options available for biomass utilization. Anaerobic digestion of animal wastes is being used extensively in developing countries to produce biogas, which is utilized directly as a fuel in burners and for lighting. An 80–20 mixture of biogas and diesel has been used effectively in biogas engines to generate electricity in small quantities.

Biomass-fueled power plants are best suited in small (<100 MW) sizes for DG to serve baseload and intermediate loads in the eastern United States and in many other parts of the world. This contribution is clean, renewable, and reduces CO2 emissions. Since biomass fuels are sulfur-free, these plants can be used to offset CO2 and SO2 emissions from new fossil power plants. Ash from biomass plants can be recycled and used as fertilizer. A carefully planned and well-managed SRWC (short-rotation woody crop) plantation program with yields in the range of 6 to 12 dry tons/acre/year can be effectively used to mitigate greenhouse gases and contribute thousands of MW of DG to the U.S. grid by the turn of the century>greater than 100mw)sizes for DG to serve baseload and intermediate loads in the eastern United States and in many other parts of the world. This contribution is clean, renewable, and reduces CO2 emissions. Since biomass fuels are sulfur-free, these plants can be used to offset CO2 and SO2 emissions from new fossil power plants. Ash from biomass plants can be recycled and used as fertilizer. A carefully planned and well-managed SRWC (short-rotation woody crop) plantation program with yields in the range of 6 to 12 dry tons/acre/year can be effectively used to mitigate greenhouse gases and contribute thousands of MW of DG.