Environmental Engineering Reference
In-Depth Information
Hydrogen is more fuel efficient than gasoline-
powered cars.
Little infrastructure exists for transport, storage, and re-
trieval of hydrogen.
Biomass
Biomass is any biologically based fuel source, such as wood, charcoal, or manure. Biomass can be grown spe-
cifically for use as a fuel or it can be grown for other uses and then reappropriated for use as fuel. Approxim-
ately 50 percent of the renewable energy in the United States is from biomass. Bagasse is the fibrous residue
biomass that remains after juice is extracted from sugarcane or sorghum stalks and is used for biofuel (biodies-
el, ethanol, or methanol) or as a renewable source of pulp for paper products. Other crops that make good bio-
fuels include switchgrass, hemp, and corn. Biomass can also be used for building materials and biodegradable
plastics.
Biomass
Advantages
Disadvantages
Biomass is an inexhaustible and renewable en-
ergy source as long as it is used sustainably.
Gases such as CO
2
are emitted during biomass burning.
There is a large potential supply worldwide.
Recycling of wastes requires greater amounts of water.
The process for biomass extraction, harvesting, and stor-
age is costly.
It is cost effective.
Biomass briquettes are much cleaner than fossil
fuels.
Only less than 30% efficient.
Plantations can be developed to provide a sus-
tainable supply.
There is a moderate to high impact on the environment be-
cause they are monoculture crops.
It can lead to soil erosion, water pollution, loss of habitat,
and loss of biodiversity.
Growth of biomass requires large amounts of land and oth-
er inputs, such as water, fertilizers, and pesticides.
Growth of the crops may utilize land and other resources
needed for food production.
Wind
Historically, windmills were used to pump water for farms and ranches. For example, the many windmills in
Holland were built to help remove water from low-lying areas reclaimed by the dikes. Today's windmills are
giant wind-powered turbines that generate electricity as they turn. More specifically, wind turns blades that are
attached to a generator, which converts the mechanical energy (wind) into electricity. Cables carry the electri-
city to the transmission line. Wind turbines clustered together are called wind farms.
