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Means to utilize the energy of the
Sun
Solar energy is the energy produced
by the sun. During the fusion process
that the sun undergoes during its lifetime,
it emits radiation. The fusion process
produces many different wavelengths
of radiation and sub-atomic particles.
Collecting and converting usable energy
from solar radiation can be accomplished
by using many different forms of technology
and includes various direct and indirect
methods of harnessing the solar energy.
There are basically two ways to use
this solar radiation, by collecting
the heat from the light, and photovoltaic
conversion of the light. There are many
different methods of collecting the
heat and converting it to electricity,
and many ways of converting the light
as well.
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One of the simplest ways that people use solar
heat energy is by using greenhouses. A greenhouse
is built so that it can best collect the sunlight
and heat that it receives from the sun. Using
special glass or plastics, the greenhouse and
everything within it retains the heat energy
from the sun. This heat is trapped inside the
greenhouse by the roof and walls allowing plants
to grow in an otherwise too cold climate.
By combining various technologies and the use
of alternative power sources such as electricity
from the grid, a controlled growing climate
can be maintained to optimize specialty and
agricultural crop growth. A large greenhouse
could make use of a solar updraft tower to generate
most or all of the additional electricity it
may require to keep the climate controlled.
A solar updraft tower is a simple use of the
excess heat generated by light heat that the
greenhouse receives. Hot air rises and is channeled
from along the ceilings of the greenhouse and
directed into a tower. The hot air rises and
the turbine blades are pushed by the hot air
rushing past them to generate electricity. Storing
any excess power in batteries for the night
when there is no sun can also keep the use of
grid power to a minimum.
Expanding on the collection of heat from the
sun, there are power plants in the hot sunny
desert areas that collect the heat from the
sun and convert the heat to electricity.
Some of these solar energy plants make use of
curved, highly reflective and focused surfaces
to optimize the collection of heat from the
sunlight. They focus the light onto a central
tube that is filled with synthetic oil that
gets very hot. This hot oil is then piped into
a boiler filled with water that is flashed into
steam from the heat of the oil. The steam produced
is then used to turn turbines that produce electricity.
This is a highly effective way to convert solar
energy into usable power.
Another way to collect the energy from the sun
is through direct photovoltaic conversion. Here
the light is converted into electricity by using
special materials called photodiodes that are
made into cells. The photodiodes emit electrons
when the photons from the sunlight hits them.
By using arrays of the special cells and electrically
connecting them together, enough power is produced
by the transduction process to make it a worthwhile
alternative energy.
As more and more people demand the use of free
solar energy, governments as well as businesses
are subsidizing researchers, and these combined
efforts are meeting this demand by coming up
with materials that can produce more and more
energy from a given amount of sunlight. Solar
electricity produced by arrays of solar panels
is now almost as cost effective as using petroleum,
coal, and nuclear generated power.
The most common method of using solar energy
is to store them in photovoltaic cells. This
method was first used in U.S. space satellites
in 1950s. The cells are made from silicon. When
sunlight enters the cells, it causes the electrons
to move about. The electrons then move towards
the front side of the solar panels. This causes
an imbalance of the electrons between the front
and back side of the panels. On joining the
two surfaces, a conductor is formed, just like
a wire, and current begins to flow. The individual
solar cells are arranged together in a PV module
and the modules are grouped together to form
an array. This current is used to charge cells
and this energy is used to light lamps, tube
lights and also to drive cars now. The current
can also be used to run appliances.
Another method of using solar energy is to direct
the solar rays to a convergence point using
a curved reflector and then make a current flowing
system like a photo cell and store energy. This
method is now used in India and U.S.
Our planet receives enough raw energy in the
form of sunlight in sixty minutes to illuminate
all of the worlds lights for a full year. Unfortunately,
a very small part of it can be harnessed so
most of the population still gets most of its
energy from power plants that burn fossil fuels.
Fortunately for our environment, we have recently
seen an increasing trend in the demand for solar
energy. This is partly due to the fact that
solar panels are becoming cheaper as technology
advances.
At the equator, the Sun provides approximately
1000 watts of energy per square meter on the
earths surface. This means that 1 square meter
of each panel can generate approximately 100
GW of raw power per year, which is enough to
illuminate more than 50,000 houses. The entire
area that would need to be covered by solar
panels to power the entire world for a year
would be the equivalent to one percent of the
entire space of the Sahara Desert. The amount
of power solar panels can generate on a given
day depends on a few variables like smog, cloudy
days, low temperatures and humidity.
Solar panel farms are a lot like other normal
power plants with the only big difference being
that most power plants get their energy from
fossil fuels. And when conventional plants burn
fossil fuels, they generate the by products
which are contributing to global warming. Solar
panel farms or solar heat plants (or CSP plants)
absorb the rays of the sun to generate electrical
energy.
This process of energy conversion in solar heat
plants is rather simple. The panels absorb the
rays of the sun, which then shines on the power
receiver. In this receiver, the energy is converted
into steam from the suns rays. The steam is
taken to tanks where it will be used to spin
turbines and generate electricity. The process
is clean because it requires no fossil fuels
to be burned. It is safe for the environment
and doesn't contribute to global warming like
conventional power plants.
If more solar panel farms are implemented, the
demand for oil will be reduced sharply. Today,
there are many households that use solar panels
for energy and more people are adding panels
every day. When this demand for solar energy
and other alternatives goes up, fewer people
will use gas and fossil fuels, and the prices
for these will surely drop as well.
Even though the initial investment into your
solar panel system is a bit expensive, the panels
will undoubtedly pay for themselves in the long
run. Not only do you save money and perhaps
even make some with your panels, you help the
environment by reducing greenhouse gases and
emissions. These systems are so durable they
have been known to last years. PV cells are
supposed to stay good anywhere from twenty-five
to forty years. Most suppliers of solar panels
have a standard twenty-five year warranty.
Finally, solar panels take minimal maintenance
and they can be placed basically anywhere that
gets a good amount of sunlight all year. Scientists
worldover say that the future lies with solar
energy. Using solar energy for home use like
heating, cooking, driving car and for all other
uses like charging your mobile phone, street
lights and heating the swimming pool and powering
your computer will become a way of life. Just
as the saying goes that sun never stops shining
in California, a solar energy home will never
lack the power required to run the house.
China is another country which is fast using
this solar technology for its future growth.
Japan already is moving in the direction of
saving its excess power and the government there
is helping device methods to save money on fuel.
The future of solar energy homes is spreading
rapidly in the east. The Ministry of Non-Conventional
Energy is formulating a program to introduce
solar energy to more than a million homes in
the next few years.
India has long days and plenty of sunshine,
especially in the Thar Desert region of Rajastan.
With abundant solar energy available, this zone
is attracting attention from the Indian government
for its research purposes. Solar energy is being
used in India for heating water for both industrial
and domestic purposes.
Human beings may not be trustworthy but the
sun is always kind and generous to mankind in
general. Let’s hope the future of solar energy
homes all over the world is not very far away. |
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