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Want to learn about energy in a fun way? Join the energy ant to
learn about energy facts, fun & games, energy history, and classroom
activities (K-12.)
HOW ELECTRICITY IS GENERATED
Did you know that most electricity generated in the United State
comes from burning coal?
In 2006, nearly half (49%) of the country's 4.1 trillion
kilowatthours of electricity used coal as its source of energy.
Natural gas, in addition
to being burned to heat water for steam, can also be burned to produce
hot combustion gases that pass directly through a turbine, spinning
the blades of the turbine to generate electricity. Gas turbines
are commonly used when electricity utility usage is in high demand.
In 2006, 20% of the nation's electricity was fueled by natural
gas.
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Petroleum can also be used
to make steam to turn a turbine. Residual fuel oil, a product refined
from crude oil, is often the petroleum product used in electric
plants that use petroleum to make steam. Petroleum was used to generate
about two percent (2%) of all electricity generated in U.S.
electricity plants in 2006.
Nuclear power is a method
in which steam is produced by heating water through a process called
nuclear fission. In a nuclear power plant, a reactor contains a
core of nuclear fuel, primarily enriched uranium. When atoms of
uranium fuel are hit by neutrons they fission (split), releasing
heat and more neutrons. Under controlled conditions, these other
neutrons can strike more uranium atoms, splitting more atoms, and
so on. Thereby, continuous fission can take place, forming a chain
reaction releasing heat. The heat is used to turn water into steam,
that, in turn, spins a turbine that generates electricity. Nuclear
power was used to generate 19% of all the country's electricity
in 2006.
Hydropower, the source
for almost 7% of U.S. electricity generation in 2006, is
a process in which flowing water is used to spin a turbine connected
to a generator. There are two basic types of hydroelectric systems
that produce electricity. In the first system, flowing water accumulates
in reservoirs created by the use of dams. The water falls through
a pipe called a penstock and applies pressure against the turbine
blades to drive the generator to produce electricity. In the second
system, called run-of-river, the force of the river current (rather
than falling water) applies pressure to the turbine blades to produce
electricity.
Geothermal power comes
from heat energy buried beneath the surface of the earth. In some
areas of the country, enough heat rises close to the surface of
the earth to heat underground water into steam, which can be tapped
for use at steam-turbine plants. This energy source generated less
than 1% of the electricity in the country in 2006.
Solar power is derived
from the energy of the sun. However, the sun's energy is not available
full-time and it is widely scattered. The processes used to produce
electricity using the sun's energy have historically been more expensive
than using conventional fossil fuels. Photovoltaic conversion generates
electric power directly from the light of the sun in a photovoltaic
(solar) cell. Solar-thermal electric generators use the radiant
energy from the sun to produce steam to drive turbines. In 2006,
less than 1% of the nation's electricity was based on solar
power.
Wind power is derived
from the conversion of the energy contained in wind into electricity.
Wind power, less than 1% of the nation's electricity in 2006,
is a rapidly growing source of electricity. A wind turbine is similar
to a typical wind mill.
Biomass includes wood,
municipal solid waste (garbage), and agricultural waste, such as
corn cobs and wheat straw. These are some other energy sources for
producing electricity. These sources replace fossil fuels in the
boiler. The combustion of wood and waste creates steam that is typically
used in conventional steam-electric plants. Biomass accounts for
about 1% of the electricity generated in the United States.
http://www.eia.doe.gov/
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Plastic Soup, ALGALITA
Kamilo Beach Debris, Hawaii
Albatross with Coat Hanger Midway Atoll
Debris Floating in Water Midway Atoll
Educating the community
Demonstrating energy efficient light bulbs
Communicating the facts about plastics