Biomass Energy
Biomass energy is energy derived from organic material produced by living or recently living organisms, chiefly plants and the wastes from agriculture, forestry and households. Because plants capture energy from sunlight through photosynthesis and store it in their tissues, biomass can be regarded as a form of stored solar energy. When this material is burned or otherwise converted, that stored chemical energy is released and can be used for heating, electricity generation or transport fuels.
The simplest use of biomass is direct combustion, in which wood, crop residues or other plant matter is burned to produce heat, which may in turn drive a steam turbine to generate electricity. More advanced processes convert biomass into more convenient fuels. Gasification heats biomass with a limited supply of oxygen to produce a combustible gas, while other processes ferment sugars and starches into ethanol or convert oils into biodiesel. Anaerobic digestion of wet organic waste yields biogas, rich in methane, which can be burned for energy.
Biomass is considered a renewable resource because the plants used can be regrown, and the carbon dioxide released during combustion was recently absorbed from the atmosphere by those plants. Its overall environmental benefit depends on how sustainably the material is produced and harvested. Biomass is one of several renewable approaches studied alongside technologies such as solar cells and solar chimneys, and it can provide a controllable supply of power that does not depend on the moment-to-moment availability of sun or wind.
Frequently asked questions
- What counts as biomass?
- Biomass includes wood, crop residues, energy crops, animal manure and organic portions of household and industrial waste — essentially any recently living organic material that can be used as fuel.
- Why is biomass called renewable?
- The plants used can be regrown within a human timescale, and the carbon dioxide released when biomass is burned was recently taken up from the air, unlike the long-buried carbon in fossil fuels.
- What is gasification?
- Gasification heats biomass with a controlled, limited amount of oxygen to turn it into a combustible gas that can be burned for heat or used to generate electricity.
