From Great Lakes Wiki
Biomass Energy comes from any biological materials that have captured some energy from sunlight, and turned it into potential chemical energy that can be released in a variety of ways. As long as the biological materials are grown in a way that allows them to be continuously renewed by the workings of nature -- sun, wind, water, soil, etc. -- then biomass energy can be considered to be renewable. As long as the methods of converting the energy in biomass into a useful form for people are non-polluting or very low-polluting, then biomass energy can be considered a form of green energy.
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