انرژی ها نو

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در این تاپیک کتابهای الکترونیکی و مقالات ایرانی و خارجی در مورد انرژی های نو قرار میگیرد

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سری اول در مورد انرژی باد هستش و فعلا روی این قضیه هستیم تا موضوع بعدی که اعلام بشه






Energy is an essential part of life. We
use energy to move and to breathe.
We even use it when we are sleeping!
This energy is supplied by the food we eat.
We also use energy to power the things that
make our lives easier and more comfortable. We use fuel
in vehicles and to heat our homes. We use electricity to run
lights, computers, and televisions. This energy has mainly been
supplied by fossil fuels, such as coal, oil, and natural gas.
More and more, however, people are looking to new sources of
energy—such as wind—to power our world.
Put simply, wind is moving air. This type of energy—the
energy of motion—is called kinetic energy. Although we
cannot see the air moving, we can feel it. The wind might be
a soft breeze that barely ruffl es our hair or a strong gust that
pushes us from one spot to another. Throughout history, people
have captured the energy from moving air and used it to power
vehicles, such as sailboats, or to operate machinery, such as
windmills.
Early Windmills
The windmill was the fi rst machine designed to use the power
of wind to do work. Early windmills were invented in the
Middle East. They were used to pump water and to grind grain
into fl our. These windmills looked very different from the

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traditional Dutch windmills
most people picture when
they think of these machines.
The first windmills used up
to 12 sails, which hung from
horizontal poles attached to a
vertical post. (A horizontal pole
runs parallel to the ground; a vertical
post is up and down, at a right angle to the ground.) In the
case of a grinding mill, the grinding stone was attached to the
same vertical post. The wind would cause the post to rotate, or
turn, which caused the grinding stone to move. This is called
a panemone design. Because the sails hang down all around
the post, this type of windmill can catch the wind from any
direction. The sails of these windmills do not have to be turned
into the wind.
Windmills were introduced
in Europe in the twelfth
century. According to some
historians, soldiers returning
from the Crusades carried the
idea for the structures home
with them from the Middle

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East. (During the Crusades,
which occurred during medieval
times, Christians from Europe
fought to take control of the
Holy Land from Muslims.) The
fi rst illustrations of a European
windmill are from 1270 A.D. They
show a design that is different
from the Middle Eastern type of
windmill. The European windmill
featured four sails, or blades,
mounted on a horizontal post,
which was attached to a gear
inside the building. A vertical
post inside the building was
attached to the same gear. As the
horizontal post spun, it moved
the gear, which turned the
vertical post. The vertical post
provided power to a grinding
stone. This type of windmill was
called a post mill. The entire
structure could be manually
rotated so that the blades would
be facing into the wind.
The structure was later
improved so that only the top
of the mill, where the blades
were mounted, moved—not the entire structure. This type of
windmill was called a tower mill. In the eighteenth century,

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another improvement
came in the form of
something called a fantail.
This small wheel, mounted
at the top of the tower
mill, automatically turns
the blades into the wind.
Generating
Electricity
People around the world
still use windmills for the
traditional tasks of raising
water or grinding grain.
Since the early 1980s,
however, people have
been using wind power
to generate electricity.
There is a great deal of
excitement about using wind power to generate electricity
because the wind is a completely renewable, clean source of
energy. The same cannot be said for the fossil fuels that supply
the majority of energy in the world today.
To create electricity, most power plants, or power stations,
burn fossil fuels to boil water. The steam produced by the
boiling water is then heated further so that it has enough
pressure to turn the blades on devices called turbines. The
blades are on one end of a long pole, or rod. The rod is
connected to a generator. The generator uses large magnets
and metal coils to produce electricity.

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What Are Fossil Fuels?
As plants and animals die, they decompose (break down) in the
earth. Over time, they become covered with layers of dirt. After
millions of years, these plant and animal remains turn into fossil
fuels. Fossil fuels can be solid, liquid, or gaseous—coal, oil, or
natural gas. People burn fossil fuels to produce energy. A home,
for example, may be heated by oil or natural gas. A power plant
may burn coal to produce electricity. For many years, fossil fuels
have been a readily available, fairly inexpensive way to provide
energy, so they have been widely used. In fact, fossil fuels
currently provide 85 percent of the energy used in the United
States. Unfortunately, however, there are problems associated
with people’s dependence on fossil fuels.
Fossil fuels are called nonrenewable energy sources. It
took millions of years for the fossil fuels we rely on today to
form. Once we have used up all of the coal, oil, and natural
gas currently under Earth’s surface, there will be no more coal,
oil, or natural gas to replace them. Fossil fuels are being used
much faster than they can form. It is impossible to determine
exactly how much longer these resources will last. Many
experts think, however, that our coal reserves may not last
longer than 130 more years. They expect oil and natural gas
to run out even sooner.
Fossil Fuels and the Environment
Another problem with fossil fuels is the negative impact they
have on the environment. Burning fossil fuels creates a type
of pollution called soot. These tiny particles mix with water
particles in the sky to create smog—a gray-brown haze that
hangs in the air. Smog has been linked to lung disorders such

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as bronchitis and asthma.
According to experts, the
pollution from coal-fi red plants
is responsible for more than
23,000 premature (early) deaths
in the United States every year.
In contrast, the technology used
in the wind industry gives off no
harmful emissions. The wind
industry has recorded only one
death among members of the
public (people who are not wind
industry workers) in 20 years of
operation. The person killed was
a German skydiver who fl ew off
course and parachuted into a
wind plant.
When coal and oil are
burned, they give off, or emit,
sulfur dioxide and nitrogen
oxides. When these chemicals
mix with other compounds in
the atmosphere, such as water
and oxygen, they create a toxic
(poisonous) solution of sulfuric
acid and nitric acid. If these
chemicals are present in areas
where there is wet weather, they
create acid rain (which also
includes acid fog, snow, and

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mist). Acid rain can harm and
even kill trees, fi sh, and other
living creatures where it falls.
In the United States, about
two-thirds of all sulfur dioxide
and one-quarter of nitrogen
oxides in the air come from
power plants that create
electricity by burning fossil
fuels such as coal.
The burning of fossil fuels
also releases greenhouse
gases, such as carbon
dioxide and methane.
Some greenhouses gases are
found naturally in Earth’s
atmosphere. They help
keep the planet’s temperature stable. Sunlight passes through
the atmosphere to strike Earth. Some of the solar energy is
absorbed, and a large amount of it bounces back toward space.
Some of the solar energy that bounces back is trapped by the
greenhouse gases that are naturally in the atmosphere. If the
right amount of solar energy is radiated back into space, the
surface temperature of Earth will remain generally constant.
Unfortunately, the emission of greenhouse gases—such as
those created by burning fossil fuels—is upsetting this balance.
In the past 150 years, there has been a 25 percent increase
in the level of certain greenhouse gases, especially carbon
dioxide, in the atmosphere. Normally, the process of plant
photosynthesis naturally regulates concentrations of carbon

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dioxide. Unfortunately, human activity produces so many
tons of carbon dioxide emissions that there is too much for
the world’s plant life to absorb. This imbalance has led to an
ongoing increase in concentrations of greenhouse gases in the
atmosphere. Experts have determined that, over time, the rising
concentration of these gases will produce an increase in Earth’s
surface temperature. Most scientists believe that these rising
temperatures may lead to changes in sea level, precipitation
(such as rainfall), and the seriousness of storms. This warming
of Earth’s surface and atmosphere is commonly referred to as
global warming or global climate change.
Climate change could affect every part of the planet. As
glaciers and large sheets of ice start to melt, sea levels could rise,
causing small islands and coastal lands to become flooded. As the
glaciers continue to shrink, other areas that rely on glacial runoff
from mountains for fresh water could face a severe shortage
of water. Rainfall in other areas could decrease drastically.
A Sustainable Solution
Global demand for all forms of energy is expected to grow
by more than 44 percent by the year 2030. Since there are
problems associated with the traditional use of fossil fuels,
many people think that finding alternative energy sources—
sustainable energy sources—should be a priority. Sustainable
energy sources can help meet the world’s needs without
harming the environment or depleting all of the resources.
To meet that goal, experts are looking at renewable energy
sources, such as wind, solar, and water power.
Wind energy is one of the fastest growing energy fields in
the world. The global capacity for wind power (in other words,

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the ability to produce electricity and other forms of usable
energy from wind power) increased 27 percent in 2007. In
2008, the United States added 8,358 megawatts (MW) of
wind-powered electricity. That is enough to power 2 million
homes. Currently, wind power supplies only 5 percent of the
energy used in the United States. The U.S. Department of
Energy (DOE) wants that to increase to 20 percent by 2030.
Right now, wind power is used to supplement (add to) other
forms of electricity. It cannot meet all of the energy needs of
the United States now—or even in the near future. There are
several factors that limit our ability to rely more strongly on
the wind for electricity. However, improvements in technology
continue to propel wind power in the right direction.