Alternative Fuel Sources - Hydrogen and Fuel Cells: Advances in Transportation and Power - page 79

would also need to be enough natural gas for a growing demand for gas-
fired power plants and fuel cells. Methanol from natural gas would have
little or no net greenhouse gas benefits in fuel cell vehicles. But, the price
of methanol may not remain competitive with gasoline if methanol de-
mand increases. Health and safety concerns would need to be solved and
direct methanol fuel cells would need to be affordable.
ENERGY FROM BIOMASS
Biomass energy comes from organic plants or animal matter. Biomass
energy or bioenergy is a general term for the energy stored in organic
wastes. The energy conversion process can range from harvesting crops
and burning them or distilling their sugars into liquid fuels. Biomass en-
ergy production can replace a variety of traditional energy sources such
as fossil fuels in solid or liquid forms. One of the most common sources
of biomass energy is wood and wood wastes. Other sources include ag-
ricultural residues, animal wastes, municipal solid waste (MSW), micro-
algae and other aquatic plants. Crops may also be grown for harvesting
their energy content. These crops include grains, grasses, and oil-bearing
plants. Medium-Btu gas is already being collected at more than 120 land-
fills in the U.S. These energy farms have the potential of providing a more
important global energy resource.
RECYCLED CARBON
Biomass technology allows the carbon in the organic matter to be
recycled. Unlike the burning of fossil fuels, the combustion of biomass
recycles the carbon set by photosynthesis during the growth of the plant.
In biomass energy production, the combustion of plant matter releases no
more carbon dioxide than is absorbed by its growth and the net contribu-
tion to greenhouse gases is zero.
Wood and wood waste includes residues from the forest and the mill.
Bark, sawdust and other mill wastes are all suitable fuels. Agricultural res-
idues include corncobs, sugar cane bagasse (the stalks after processing),
leaves, and rice hulls. MSW materials include paper products, cloth, yard
wastes, construction debris, and packaging materials.
Biomass materials depend on local conditions. In tropical areas, sug-