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Biomass Energy

Biomass energy (bioenergy) is derived from organic matter. Wood is an example of a source of biomass energy. Other forms include: plants, residues from agriculture and forestry, municipal and industrial wastes, and methane and other gases from landfills. The use of biomass energy aids in the reduction of greenhouse gas emissions. While biomass releases about the same amount of carbon dioxide as fossil fuels, the net amount of carbon dioxide remains at zero if the growth of new plants reduces the carbon dioxide in the atmosphere. This “recycling” of carbon dioxide works if plants are grown for the purpose of collecting biomass energy. Such plants form part of a biomass feedstock and involve trees and grass that grow quickly.


Biomass can be used to make the same products that are created by fossil fuels, sometimes using less energy to do so. Biofuels are created by releasing the sugars in the starch and cellulose in plants. Additionally, when biomass is heated, carbon monoxide and hydrogen (biosynthesis gas) is produced in great amounts to be later used in the production of plastics, acids, and synthetic fabrics.


Biofuels can be used to power cars, airplanes, and trains. The two principal biofuels are ethanol and biodiesel. Ethanol is produced by fermenting and brewing biomass. Flexible-fuel vehicles can run on about 85% ethanol. Biodiesel is the combination of alcohol, vegetable oil, animal fat, and recycled cooking grease. It can used to both reduce vehicle emissions and in a pure form, act as a renewable alternative for diesel engines. Biofuels also include methanol and reformulated gasoline components.


Biopower is the use of biomass to generate electricity. Types of biopower systems include direct-fired, gasification, anaerobic digestion, pyrolysis, and small, modular systems. Direct-fired systems consists of burning bioenergy feedstocks to produce steam, which is then captured by turbines that spin a generator, eventually creating electricity. Gasification is used to convert biomass into a gas. The gas is used to power a gas turbine, which spins an electric generator. Anaerobic digestion describes the process by which bacteria in organic matter decompose without the use of oxygen; the result is extractable methane that is used as a source of energy. Pyrolysis involves the conversion of biomass into a liquid state through a heating process. This liquid fuel can then be used to generate electricity in the same way that petroleum can. Modular systems are designed for small town or individual consumer use.
(Information gathered from the National Renewable Energy Laboratory page on biomass energy:

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