sun is the most abundant source of energy available to mankind. Utilizing
solar energy has the of benefit lessening our dependence on fossil fuels,
which in turn reduces the ecological damage that occurs by extracting
these fuels from the earth, as well as through their extended use. Solar
also has the added benefit of being an infinitely renewable resource.
The energy produced by the sun is due to a process called the proton-proton
chain. The sun is made from mostly hydrogen, and the intense heat and
pressure inside the core causes these hydrogen atoms to fuse together,
forming an atom of helium. Helium has less mass than the total of the
four atoms of hydrogen that are fused together to form it. The excess
mass is expelled as energy, which can be mathematically explained by
Einstein’s equation E=mc².
This process of nuclear fusion is what makes the sun shine and produces
heat. There are billions of such reactions happening everyday inside
the sun. In order to maintain its current energy output, the sun has
to convert approximately 600 million tons of hydrogen into helium every
second. Even at this incredible rate of fusion, the sun still contains
enough hydrogen to continue the process for the next several billion
Solar energy can create numerous sources of power. The most commonly
recognized method is through the conversion of direct sunlight to electricity.
This process utilizes a semiconductor material, usually silicon, which
releases electrons when exposed to light energy from the sun. Electrical
conductors are attached to either side of the material, positive on
one end and negative on the other. These conductors form an electrical
circuit causing the freed electrons to flow from one end to the other,
creating an electrical current.
This process, known as the photoelectric effect, is how solar panels
create electricity. Each panel is an assembly of individual solar cells
that are linked together in order to produce the needed electricity
for a given application. This technology can be used to power homes
and businesses, and has been used in many other applications as well.
Solar energy is also responsible, indirectly, for many other alternative
power sources. Wind, for example, is created when light energy from
the sun heats the surface of the planet, causing a convection effect.
Hot air rises and is transferred to cooler areas where it flows back
down to earth. This movement of air is defined as wind. Energy is can
be harnessed from this convection process using wind turbines. The wind
causes the turbine to spin, which in turn powers an electrical generator
and creates electricity.
Fossil fuels also owe their existence to solar energy. Oil, natural
gas and coal exist today because of the decayed remains of plants and
animals from millions of years ago. These ancient plants, like those
of today, existed due to energy supplied by the sun. As the plants and
the animals that fed on them died, they were preserved and transformed
into fossil fuels through pressure, heat, and biological processes.
Solar energy can be indirectly linked to many other sources of power
like hydro-electric (due to the rain cycle transferring evaporated water
from the oceans onto land, forming lakes and rivers) and wave power
(caused by wind, which is a result of air movement due to the heating
effects of the sun). Because our planet’s natural resources are
finite, finding new ways to harness the energy of the sun is increasingly
important. Direct use of solar energy, as well as taking advantage of
indirect sources, will be of tremendous benefit in the future.