The term refers to biological or organic material that serves as a renewable source of energy either by being burned directly (like wood) or by being converted to a fuel source, called biofuel.  Examples of the latter include plants like miscanthus, switchgrass, hemp, corn (to make ethanol), willow, sugarcane and trees like eucalyptus, and even animal and municipal waste.  Its importance is an alternative to fossil fuels, such as oil, coal, and gas, which have serious adverse environmental effects, especially the release of carbon dioxide (CO2), a greenhouse gas (GHG).  With biomass, the organic material absorbs the sun’s energy through photosynthesis and captures CO2.  So when it is burned it is often merely returning to the atmosphere the CO2 that it captured.  But harvesting or production of biomass energy can damage ecosystems, produce harmful air pollution, consume large amounts of water, and produce net greenhouse emissions so it needs to be done thoughtfully.

Farmers are often changing their crops from being used as a food source to use as a fuel source, largely because as a fuel the crops earn more money.  The problem has developed that switching those crops that produce food to fuel may be helping to create substantial food price rises and food shortages, but this is a complex issue that requires more study.  A recent report from NRDC points put how biomass crops can provide extra money for farmers without diverting crops from food and feed markets.

Some further ideas to explore on Biomass:

Identify the organic materials in your area that are being used to produce energy.

Identify the organic materials in your area that could be used to produce energy.

Determine how local farmers could earn more income from planting and harvesting a biomass source for energy either in addition to or instead of what they do now.

Sources:

Biomass: an important source of renewable energy www.biomass.net/

Union of Concerned Scientists: Citizens and Scientists for Environmental Solutions, “How Biomass Energy Works,”

www.ucsusa.org/clean_energy/technology_and_impacts/energy_technologies/how-biomass-energy-works.html

European Environment Agency, “Biomass,” glossary.en.eea.europa.eu/terminology/concept_html?term=biomass

“Food vs. fuel” in Wikipedia en.wikipedia.org/wiki/Food_vs._fuel

Natural Resources Defense Council (NRDC), Second harvest: Bioenergy from Cover Crop Biomass” (NRDC Issue Paper, March 2011) www.nrdc.org/energy/covercrops.asp