What Is Solar Energy
Why ask the question,
"What is solar energy?"
Well, when you are looking at the option of using solar power, whether
it is
for a small solar-powered gadget or a large system to power
your home
or business,
it helps to understand that question as well as "how is solar energy
produced?"
With some basic information, it is easier to understand the limitations
of use as well as the
potentials
of this unlimited source
of energy and power.
What
is Solar Energy - Production of Energy by the Sun
The definition of solar energy according to the American Heritage
Science Dictionary is:
- The radiant energy emitted by the Sun.
- Energy derived from the Sun's radiation.
Solar
energy is energy produced by the sun as a result of nuclear fusion.
It is radiant energy,
or energy that comes in the form of
electromagnetic waves. In this form, energy can cross the hundreds of
thousands
of miles of space from the sun to our planet without losing its energy.
Since the sun is round,
the energy is radiated out in all directions
and only a very tiny part of the sun’s total energy ever hits the
earth.
Solar energy also travels
a great distance across space at the speed of
light and only reaches earth after 8-1/2 minutes.
What
is Solar Energy - Three Basic Parts
The
energy coming from the sun can be divided into three basic parts as
it affects the earth.
Here they are stated in a somewhat simplified manner that is easy to
understand:
- Visible light
- Electromagnetic waves that we can see
- Thermal energy
- Longer waves that are sensed as heat
- Ultraviolet
solar energy - Shorter waves that cause skin damage, for
example.
What
is Solar Energy - Solar Energy and the Earth
As you can see from the
chart below, about a third of the sun's
energy is reflected back out into space.
So about two-thirds of
the sun's energy that hits the earth is absorbed
by the earth's surface, the clouds, and bodies of water.
Although, as we have seen, only a tiny portion of the sun's total
energy reaches the earth, that small part is really an amazingly-huge
source of
energy.
For example, if we could
capture and use the sun's energy that reaches
the earth in just one hour, we could supply the whole world's demand of
energy
for one full year.
Needless to say, that is just not possible at this point in time.
Solar Energy - Potential for Renewable Energy Alternative
Solar
energy in its natural form only reaches portions of the earth
during daylight hours; however, the heat stored by water
and the earth-s
surface continues to be released during the dark hours.
The fact that solar
energy can be stored and used when needed is what makes it such a
potential source of usable energy.
Next see:
Solar Energy Efficiency
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