The term biomass refers to organic matter such as trees, grasses, agricultural crops, municipal and industrial waste or other biological material that can be used for fuel. Biomass may be burned directly in its solid form, or processed or refined to liquids or gases for the production of electric power, heat, chemicals, or fuels. Examples of such fuels are bioethanol, biobutanol and biodiesel. Biomass may also include animal waste which may be burned as fuel.
Wood is among the most common and commonly used biomass fuels. In most cases solid wood is the least expensive home heating fuel of any variety. Plants such as hemp, corn, switchgrass and sugar cane are other sources of biomass fuels. These sources are generally renewable, provided they are managed wisely.
Biomass does not include fossil fuels such as coal or petroleum which have been transformed from organic material by geological processes. Fossil fuels are not renewable.
The main source of greenhouse gasses in our atmosphere comes from the burning of fossil fuels. When fossil fuels burn, they release carbon dioxide (CO2) which has been trapped in them for millions of years below the surface of the earth. Doing so thus significantly increases atmospheric CO2 in a relatively short period of time. Increased concentrations of CO2 in the atmosphere trap the sun's heat close to the earth and cause the average global temperature to rise.
When biomass fuels are burned, they also release CO2 into the atmosphere. However, they make no net contribution to CO2 concentrations. A similar amount of CO2 would be released if equal amounts of the biomass fuel source were either burned or allowed to decompose naturally. The CO2 released from burning biomass fuels is balanced by the CO2 captured in the growth of the biomass source material. Consequently, the combustion of biomass fuels does not contribute to the problem of climate change as does the combustion of fossil fuels.
Biomass is one of our most important energy resources, particularly if it is burned efficiently. Biomass use strengthens rural economies, decreases dependence on imported oil, avoids use of highly toxic fuel additives, reduces air and water pollution, and reduces greenhouse gas emissions.
Currently biomass fuel accounts for about three percent of the primary energy production in the United States.
