Biomass is energy derived from plant or plant products. Plants are producers and are capable of converting solar energy into chemical energy. When combusted, carbon dioxide is released, which adds to greenhouse gases which can lead to global warming. Wood is a traditional biomass fuel which has been used by humans for thousands of years. Other examples include dung and garbage which can be combusted to release energy. These are used to produce methane gas which is an excellent fuel source. Corn and other plants can be harvested to produce ethanol-- a fuel that can power vehicles. Biomass works on the principle that the energy stored in something that was once alive can be released again by the process of combustion.
Biomass, as a renewable energy source, is biological material from living, or recently living organisms.As an energy source, biomass can either be used directly, or converted into other energy products such as biofuel. In the first sense, biomass is plant matter used to generate electricity with steam turbines & gasifiers or produce heat, usually by direct combustion. Examples include forest residues (such as dead trees, branches and tree stumps), yard clippings, wood chips and even municipal solid waste. In the second sense, biomass includes plant or animal matter that can be converted into fibers or other industrial chemicals, including biofuels. Industrial biomass can be grown from numerous types of plants, including miscanthus, switchgrass, hemp, corn, poplar, willow, sorghum, sugarcane, and a variety of tree species, ranging from eucalyptus to oil palm (palm oil).
Biomass energy is energy produced by burning biomass. Biomass is a broad category of material encompassing all the living matter in an area. Wood, crops and crop waste, and wastes of plant, mineral, and animal matter comprise much of an area's biomass. Much of this material is considered "garbage" and ends up in landfills.
It has been estimated that 90 percent of U.S. waste products could be burned, thereby providing the equivalent energy of 100 million tons of coal (20 percent of waste products will not burn though they can be recycled). In Western Europe, there are more than 200 power plants that burn rubbish (garbage) to produce electricity.
Biomass can also be converted into energy-providing biofuels, such as biogas, methane, methanol, and ethanol. However, the biofuel production process is more expensive than the conventional fossil fuel processes.
Rubbish buried in the ground naturally yields methane gas during anaerobic decomposition (the decaying of organic matter in the absence of oxygen). One ton of refuse can produce 8,000 cu feet (227 cu meters) of methane. Worldwide, there are 140 methane-collecting operations that tap into underground rubbish.
Some crops, such as sugar cane, sorghum, ocean kelp, water hyacinth, and various species of trees, are grown specifically to be burned for biomass energy.
Sources: Cunningham, William, and Barbara Woodhouse Saigo. Environmental Science: A Global Concern, pp. 384-86; How in the World?: A Fascinating Journey Through the World of Human pp. 118-19; Wright, R. Thomas. Understanding Technology, p. 72.