Energy Sources
Have you ever thought about how we get the energy to run the things we
take for
granite every single day. There are many sources of energy that that
are used
for transportation, heat, light, and the manufacturing of goods of
all kinds.
The development of science and civilization is closely linked
to the
availability of energy in useful forms. The seven main energy sources
are fossil
fuels, hydroelectric, solar power, win power, geothermal, nuclear
power, and
biomass energy. By harnessing the sun, wind, falling water, plant
matter, and
heat from the earth, energy planners expect to decrease the
environmental impact
on energy use. Most of the nonhydro renewable power
comes through some form of
combustion, such as the burning of biomass,
landfill gas, or municipal solid
waste. Little electricity comes from solar,
wind, and geothermal sources.
Factors that are increasing interest in
renewable energy include cost advantages
in niche markets, regulatory
pressures, customer service requirements, fuel
flexibility, and security. One
of the biggest source of energy is fossil fuels.
Fossil fuels have served
as a reliable source of heat for cooking and warmth
since the beginning of
history. The common fossil fuels are coal, peat, lignite,
petroleum, and
natural gas. Coal gas, coke, water gas, and producer gas can be
made by using
coal as the principal ingredient. These such artificial gases can
be used for
fuel, illuminant, and a source material for the manufacturing of
synthetic
ammonia. Gasoline, kerosene, and fuel oil are made from petroleum.
They
are mainly used for transportation if the fuel is used in a liquid
form.
Natural gas is a natural mixture of gaseous hydrocarbons found from
the ground
or obtained from specially driven wells. The composition of
natural gas varies
in different localities. It is used extensively as an
illuminant and a fuel.
Some geologists theorize that natural gas is a
by-product of decaying vegetable
matter in underground strata. Others think
it may be primordial gases that rise
up from the mantle. Natural gas was
known to the ancients but was considered by
them to be a supernatural
phenomenon because it appeared as a mysterious fire
bursting from the ground.
Gas is also a fossil fuel. It is a gaseous substance
that burns in the air
and releases enough heat to be useful as a fuel. It is
advantageous if a fuel
gas is readily transportable through pipes and is easily
liquefied. Oil gas
is a type of gas made by applying heat to various petroleum
distillates. Its
principal use is as a supplement to natural gas during periods
of heavy
demand. Coal gas may be any of a variety of gases produced by heating
coal in
the absence of air and driving off the volatile constituents. It is not
as
high in fuel value as other gases and often contains tars, light
oils,
ammonia, and hydrogen sulfide. These common fuels are used in
industry,
transportation, and the home are burned in the air. Scientists
research and
develop alternatives to gasoline every single day. One possible
alternative is
methanol, which can be produced from wood, coal, or natural
gas. Another
possibility is ethanol. Ethanol is an alcohol produced from
grain and currently
used in some types of US gasoline. A example of this is
gasohol. It is a
compressed natural gas, which is much less polluting than
gasoline and is
currently used by a half-million vehicles around the world.
Petroleum is a
fossil fuel thought to have been formed over millions of years
from incompletely
decayed plant and animal remains buried under thick layers
of rock. The
widespread burning of petroleum products as fuels has resulted
in serious
problems of air pollution. Oil spilled from tankers and offshore
wells has
damaged ocean and coastline environments. The environmentally
disruptive effects
of oil wells have sometimes led to strong opposition to
new drilling, as in
wilderness areas of Northern Alaska. Most of the energy
consumed is ultimately
generated by the combustion of fossil fuels, such as
coal, petroleum, and
natural gas. The world has only a finite supply of these
fuels, which are in
danger of being used up. Also the combustion of these
fuels releases various
pollutants, such as monoxide and sulfur dioxide, which
pose health risks and may
contribute to acid rain and global warming.
Environmentalists have become
increasingly alarmed in the latter half of the
20th century at the widespread
destruction imposed on sensitive wild lands
during the exploration. Some
examples of these wild lands are the tropical
rainforests, the arctic tundra,
and coastal marshes. Hydroelectric power is
an important source of energy.
Hydroelectric power or water power is a
mechanical energy derived from falling
or flowing water, such as rivers,
streams, and the overflow of dams. Water
flowing from a higher level to a
lower level (a dam or waterfall) is used to
activate a turbine that drives an
electric generator. The amount of power
furnished is proportional to the rate
of flow of water and the vertical distance
through which it falls. During
high demands the facility produces electricity by
using the water that flows
down the reservoir. A dam is a barrier to hold back
water. They are commonly
across a watercourse and often forming a reservoir or
lake. Dams are made of
timber, rock, earth, masonry, or concrete or of
combinations of these
materials. Timber is used in dams because timbers are
impermanent and their
height is limited. Rock dams consist of an embankment of
loose rock with
either a core impervious to water or a watertight face on the
upstream side.
Earth dams may be either simple embankments of earth or
embankments
reinforced with a center of cement. Masonry and concrete dams are
either
gravity dams or arch dams. Gravity dams are dependent upon their own
weight
for resistance to the pressure of the water. Arched dams are curved
upstream
and are usually constructed in narrow canyons or gorges where the rocky
side
walls are strong enough to withstand the tremendous lateral thrust of the
dam
that is caused by the pressure of the water. Most dams are constructed
for
multiple purposes. To provide for irrigation, to aid flood control and
help
improve the navigability of waterways, and especially to furnish power
for
hydroelectric plants. Some dams built to provide hydroelectric power
include the
Aswan dam and the Itaipu Dam. The Aswan High Dam is one of
the world's largest
dams. It is located on the Nile River in Egypt. The dam
is 4 miles long, 375
feet high and 11,811 feet long. The dam has a
hydroelectricity capacity of 10
billion kWh. The downfalls of hydroelectric
is that is it is a very expensive
project to build these such dams. Most of
the energy consumed from the dams can
only be used within 100 mile radius.
The last downfall is that you have to have
a large body of water to have a
dam, therefore many areas of the world don't
have these bodies of water.
Another source of energy is solar power. The earth
receives huge amounts of
energy every day from the sun, but the problem has been
harnessing this
energy so that it is available at the appropriate time and in
the appropriate
form. Solar power or solar energy is only received during the
daylight hours,
but more heat and electricity for lighting are needed at night.
Solar
energy is expected to become a more viable and competitive source of
energy
by the end of the 20th century. Several solar thermal power plants are
now in
operation in California, but they are not yet able to compete
with
conventional power plants on an economic basis. Some forms of solar
energy are
light, radio waves, and X rays. Solar energy is needed by green
plants for the
process of photosynthesis. It is the ultimate source of most
foods. Natural
collection of solar energy occurs in the earth's atmosphere,
oceans, and plant
life. The photovoltaic cell is a semiconductor diode that
converts light to
electric current. When light strikes the exposed active
surface, it knocks
electrons loose from their sites in the crystal. Practical
photovoltaic cells
are currently about 10 to 15% efficient. Solar cells have
long been used to
provide electric power for spacecraft. One important solar
energy application
concentrators is a solar furnace. They are ideal for
research requiring high
temperature and contaminant-free environments. Solar
cooling can be achieved
through the use of solar energy as a heat source in
an absorption cooling cycle.
Solar power research is being pursued in
connection with efforts to design
residential and commercial buildings that
will use energy more efficiently. Some
other promising devices are solar
collectors and solar mirrors. Solar energy is
a very expensive process that
take years to develop the technology for it. This
energy can only be used in
the daylight ( when the sun is out ), so during the
night you wouldn't have
energy then. Another important source of energy is wind
power. The most
popular device is a mechanical device that harnesses wind power
in order to
pump water, grind grain, power a sawmill, or drive an electrical
generator.
This device is called a windmill. Windmills were probably not known
in Europe
before the 12th century, but then they became the chief source of
power until
the steam engine. The windmill is very useful on farms where farmers
need
water to irrigate their crops on the farm. The windmill pulls water
from
underground water wells so it can be used for irrigation. The windmill
is also
made for decoration and sold for large amounts of money. It is very
expensive to
make and you have to have a large land space to put a windmill
on. Also, the
windmill makes so much noise that it can't be put near any
houses. A wind
turbine is used to generate electricity. They are even
designed to on in light
winds. The wind turbine is a huge invention to make
work easier, throughout the
whole course of time. The next important energy
source is a type of energy
called geothermal energy. Geothermal energy is
based on the fact that the earth
is hotter, when drilled deeper below the
earth's surface. Some scientists have
suggested using the earth's internal
heat as a source of energy. Such energy
derives from steam trapped deep in
the earth. Brought to surface, it will drive
a turbine to produce
electricity. Geothermal energy is released naturally in
geysers and
volcanoes. In California, 7% of the state's electricity is generated
by the
geothermal plant complex known as the Geysers, which have been in
production
since 1960. The energy we get from the ground is then transferred
into energy
through a long and expensive process. We can drill into the earth's
surface
and get the energy from many places throughout the world. It is much
easier
to get this energy than getting it from a windmill. Geothermal energy is
used
in electric power generation and direct heat applications such as
space
heating and industrial drying processes. It was developed for
electrical power
in 1904 in Tuscany, Italy, where power production continues
today buildings in
the vicinity. A hot spring is a form of geothermal energy
that is a natural
discharge of groundwater that has a elevated temperature.
Most hot springs
result from the emergence of groundwater that has passed
through or near
recently formed hot igneous rocks. Iceland, Yellowstone Park,
and North Island
of New Zealand are known for their hot springs. A geyser is
a hot spring which
water and steam are ejected periodically to heights
ranging from a few to
several hundred feet. Geothermal generating plants use
geysers to produce
electricity. Nuclear power is another important energy
source. Nuclear power or
nuclear energy is the energy stored in the nucleus
of an atom and released
through fission, fusion, or radioactivity. The
release of nuclear energy is
associated with changes from less stable to more
stable nuclei and produces far
more energy for a given mass of fuel than any
other source of energy. The
development of nuclear energy made available
another source of energy. The heat
of a nuclear reactor can be used to
produce steam. Then it can be directed
through a turbine to drive an electric
generator. The reactor is so constructed
that the fission of atomic nuclei
produces a self-sustaining nuclear chain
reaction, in which the produced
neutrons are able to split other nuclei. Nuclear
energy is measured in
millions of electron volts. Any electric power generating
plant is one part
of a total energy cycle. The uranium fuel cycle that is
employed for LWR
systems currently dominates worldwide nuclear power production.
This
cycle has many steps and takes a lot of time and money. If any nuclear
items
spill or contaminate anything a special team is brought in with special
suits
to clean it up. Nuclear energy is said to be here on earth for a very
long
time. The last energy source is biomass energy. Biomass energy is the
fuel
energy that can be derived directly or indirectly from biological
sources.
Biomass energy from wood, crop residues, and dung remains the
primary source of
energy in developing regions. In a few instances it is also
a major source of
power, as in Brazil, where sugarcane is converted to
ethanol fuel. In China's
Sichuan province fuel gas is obtained from dung.
Various research projects aim
at further development of biomass energy, but
economic competition with
petroleum has mainly kept such efforts at an early
development stage. Corncobs
are an important source of furfural, a liquid
used in manufacturing nylon fibers
and phenol-formaldehyde, refining wood
resin, making lubricating oils from
petroleum, and purifying butadiene in the
production of synthetic rubber. Ground
corncobs are used as a soft-grit
abrasive. Large, whole cobs from a special type
of corn,"cob pipe"corn are
used for pipes for smoking tobacco. Corn
oil is extracted from the germ of
the corn kernel and is used as a cooking and
salad oil and in solid form as
margarine. It is also used in the manufacture of
paints, soaps, and linoleum.
The search for alternate sources of energy has made
corn an important fuel
source. It is also processed to produce alcohol for use
with gasoline as
gasohol and the dry stalk is a fuel biomass. The cons for
biomass energy is
that the items used in this cycle is so scarce that it is very
hard to find.
One time in the future all of the items will be unavailable and
cannot be
used. The demand for energy has increased steadily, not only because
of the
growing population but also because of the greater number of
technological
goods available and the increased affluence that has brought these
goods
within the reach of a larger proportion of the population. Despite
the
introduction of more fuel-efficent automobiles, the consumption of
gasoline by
vehicles in America increased by 18% between 1973 and 1989. The
rise in gasoline
consumption is attributed to an increase in the number of
miles the average
person travels and to a 42% increase from 1973 to 1989 in
the number of cars on
the road. By harnessing the sun, wind, falling water,
plant matter, and heat
from the earth, energy planners expect to decrease the
environmental impact of
energy use. In this vision for the future, renewable
energy sources would
complement fossil fuels and, eventually, emerge as a
significant energy source.
Despite various legislative incentives over
two decades toward this goal in the
US, however only a small fraction of
electricity needs are supplied by renewable
energy technologies other than
hydropower. Most of the nonhydro renewable power
comes through some form of
combustion, such as the burning of biomass, landfill
gas, or municipal solid
waste. Relatively little electricity comes from solar,
wind, and geothermal
sources. The limitations on renewable energy's progress to
date result from
its relatively high cost and the economics of the utility
industry. It is
faced with an increasingly competitive environment and is
generally awash in
surplus power. Although renewable energy technologies have
overcome a number
of formidable technical hurdles to bring costs down and
increase reliability,
further progress has been prevented by the lower cost of
natural gas and the
efficiency of gas-fired generating plants. As costs continue
to decline, the
renewable energy market can be expected to grow, particularly if
possible
global warming trends continue to be linked with greenhouse gases such
as
those emitted by fossil fuels. Other factors are that increase interest
in
renewable energy include cost advantages in niche markets, regulatory
pressures,
customer service requirements, fuel flexibility, and security.