Solar energy
More number of images and information have been
used for better understanding, you can skip lot of
images and description for exam point of view
,• The electromagnetic energy emitted by the sun is called solar radiatio
solar energy (or solar heat). Tremendous amounts of energy are crea
within the sun, and only a fraction of this energy reaches earth in the
of electromagnetic waves after multiple interactions with the atmosp
The radiation energy emitted or reflected by the constituents of the
atmosphere form the atmospheric radiation. This keeps earth at a
temperature suitable for life. The amount of solar energy reaching ea
surface can easily meet all energy needs of the world. However, this
practical due to the low concentration of solar energy and its relative
high cost. Other renewable energies such as geothermal, wind, hydro
biomass appear to be less costly than direct solar energy, but their
potentials with the current technologies are also much less than dire
solar energy. Solar energy reaches earth by radiation.
,• The sun is a nearly spherical body that has a diameter of D= 1.393 x 10 m an
mass of m = 2 x 10" kg and is located at a mean distance of L = 1.496 x 10" m
from the earth. It emits radiation energy continuously at a rate of E= 3.8 x 10
W. Less than a billionth of this energy (about 1.7 x 107 W) strikes the earth.
• The sun generates energy by a continuous fusion reaction during which two
hydrogen atoms fuse to form one atom of helium. Therefore, the sun is
essentially a nuclear reactor, with temperatures as high as 40,000,000 K in it
core region. The temperature drops to about 5800 K in the outer region of th
sun, the convective zone, as a result of the dissipation of this energy by
radiation. The solar energy reaching the earth's atmosphere is called the tot
solar irradiance Gs, whose value is Gs = 1373 W/m2
• The total solar irradiance (also called the solar constant) represents the rate
which solar energy is incident on a surface normal to the sun's rays at the ou
edge of the atmosphere when the earth is at its mean distance from the sun
, • The total solar irradiance
called the solar constant
represents the rate at w
solar energy is incident o
surface normal to the su
rays at the outer edge of
atmosphere when the ea
at its mean distance from
sun. The accepted value
solar constant is 1373 W
(435.4 Btu/h-ft'), but its
changes by 3.5 percent f
maximum of 1418 W/m
January 3, when the ear
closest to the sun, to a
minimum of 1325 W/m
July 4, when the earth is
farthest away from the s
More number of images and information have been
used for better understanding, you can skip lot of
images and description for exam point of view
,• The electromagnetic energy emitted by the sun is called solar radiatio
solar energy (or solar heat). Tremendous amounts of energy are crea
within the sun, and only a fraction of this energy reaches earth in the
of electromagnetic waves after multiple interactions with the atmosp
The radiation energy emitted or reflected by the constituents of the
atmosphere form the atmospheric radiation. This keeps earth at a
temperature suitable for life. The amount of solar energy reaching ea
surface can easily meet all energy needs of the world. However, this
practical due to the low concentration of solar energy and its relative
high cost. Other renewable energies such as geothermal, wind, hydro
biomass appear to be less costly than direct solar energy, but their
potentials with the current technologies are also much less than dire
solar energy. Solar energy reaches earth by radiation.
,• The sun is a nearly spherical body that has a diameter of D= 1.393 x 10 m an
mass of m = 2 x 10" kg and is located at a mean distance of L = 1.496 x 10" m
from the earth. It emits radiation energy continuously at a rate of E= 3.8 x 10
W. Less than a billionth of this energy (about 1.7 x 107 W) strikes the earth.
• The sun generates energy by a continuous fusion reaction during which two
hydrogen atoms fuse to form one atom of helium. Therefore, the sun is
essentially a nuclear reactor, with temperatures as high as 40,000,000 K in it
core region. The temperature drops to about 5800 K in the outer region of th
sun, the convective zone, as a result of the dissipation of this energy by
radiation. The solar energy reaching the earth's atmosphere is called the tot
solar irradiance Gs, whose value is Gs = 1373 W/m2
• The total solar irradiance (also called the solar constant) represents the rate
which solar energy is incident on a surface normal to the sun's rays at the ou
edge of the atmosphere when the earth is at its mean distance from the sun
, • The total solar irradiance
called the solar constant
represents the rate at w
solar energy is incident o
surface normal to the su
rays at the outer edge of
atmosphere when the ea
at its mean distance from
sun. The accepted value
solar constant is 1373 W
(435.4 Btu/h-ft'), but its
changes by 3.5 percent f
maximum of 1418 W/m
January 3, when the ear
closest to the sun, to a
minimum of 1325 W/m
July 4, when the earth is
farthest away from the s
