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The Need for Solar Energy
Fossil fuels provide roughly 85% of the world’s total energy. One day, these fossil
fuels will run out, or stifle the world with pollution. A feasible solution to this
problem is solar energy. With a limitless supply, the sun can forever provide the
world with the energy we depend on. Scientist and engineers are working to find
efficient and cost friendly ways to harness the sun’s energy by using solar cells.
The more time that passes, the higher the demand for energy gets. The fossil fuels
that are used for this energy will not be able to keep up with the rise in demand.
Solar energy is the best solution to this problem. The sun provides us with more
than enough energy we use each day. The sun is a source of energy that won’t run
out for billions of years. The energy the sun sends us is environmentally clean and
we get it free of charge. However, there are many barriers around solar energy.
Solar energy has good and bad perks, it is limitless and clean, but it is very
inefficient and costly. Solar energy is transferred from light to electricity by solar
cells. Many solar cells can be found in calculators, satellites and even advertising
signs. The current problem with solar cells however, is their efficiency. Solar cells
are now made with silicon, an abundant metal found naturally, which only provides
from 10 to 20 percent efficiency. This poor outcome makes the cost for solar energy
much higher than that of fossil fuels. The need for a better efficiency is necessary for
solar energy to become more prevalent in the world.
Scientists have begun using exotic materials and new developments in
nanotechnology for solar cells. Nanotechnology involves working with structures
the size of molecules and atoms (one nanometer is equal to one-billionth of a
meter). Structures this small can transmit electricity more efficiently and can
contain the energy photons more efficiently. While testing different materials with
nanotechnology, scientists found great improvements in the efficiencies. The use of
lead and the element selenium has been projected to yield over 60% when used in
small quantities. However, this materials need to be pure, which is very costly.
There are ways to convert solar energy into electricity cheaply, but it is not as
efficient.
The main problem with the cost of solar energy is the necessary purity of the
materials. The current solar cells call for such pure materials because impurities
block the flow electricity throughout the cell. An impure material would be less
efficient, more cost effective. A bigger problem than the efficiency is how to store the
energy.
The sun is not available at all times of the day, mostly due to the weather and
nighttime darkness. Different types of batteries have been discovered to store
energy for those periods of time, but the batteries are not capable of storing large
quantities of energy. There are other ways to store energy other than batteries and a
new way to store energy more efficiently will be needed in the future. Scientists are
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working on a way to mimic the process plants use to gain energy from the sun,
called photosynthesis. In photosynthesis, plants store their energy in the bonds of
molecules for food. This natural process is not easy to mimic and is almost
impossible to with the same efficiency. A breakthrough in finding a way to store the
energy in the bonds of molecules efficiently would enhance the attractiveness of
solar energy.
There needs to be many advances in the technology for solar energy to be a main
source of power. A new discovery in materials or a technology that stores the energy
more efficiently would be a massive breakthrough. Mastering the energy given to us
by the sun is a feat that must be met in the near future.
http://encyclopedia.kids.net.au/page/so/Solar_cell
http://www.engineeringchallenges.org/cms/8996/9082.aspx