Renewable Energy sources

1. Department of Artificial
Intelligence & Machine Learning
K.S INSTITUTE OF
TECHNOLOGY
Kammavari Sangham (R) 1952,K.S. Group of Institutes
Group No: 12
CHIRAG GOWDA
BHARATH R
HARISHA
KUSHALA B GOWDA
Guided By:
1
No.14, Kanakapura Rd, Raghuvanahalli, Bangalore- 560109
Affiliated to VTU, Belagavi & Approved bu AICTE, New Delhi,
Accredited by NBA, NAAC & IEI
SOLAR CONSTATNT, SOLAR ESTIMATION,
FLATE PLATE COLLECTORS AND SOLAR POND

2. 2
SOLAR
CONSTANT

3. • Solar constant is the amount of the incoming solar
radiation per unit area, measured on the outer
surface of the Earth’s atmosphere, in a plane
perpendicular to the rays.
• The solar constant which is denoted by the symbol
GSC is a flux density which is the measuring mean of
solar electromagnetic radiation.
• It is the solar irradiance per unit area.
• It is said to be measured on a surface perpendicular
to the rays that is one astronomical unit denoted by
AU from the Sun which is roughly the distance from
the Sun to the planet.
• The solar constant includes all types of solar
radiation and not just visible light.
3

4. • To quantify the rate at the unit surface of a solar panel in
which the energy is received upon the solar constant is
used.
• In this case, the solar constant is absorbed at a given point
and provides a total measurement of the sun's radiant
energy.
• They are used in several atmospheric and geological
sciences.
• The solar constant is just nearly constant. Once every eleven
years, the relative constant varies by 0.2% in a cycle that
peaks.
4

5. • In 1838, Claude Pouillet made the first attempt to estimate the
solar constant at 1.228 kW/m2.
• At a solar minimum of 1.361 kW/m2 and a solar maximum of 1.362
kW/m2, the constant is rated.
• To measure the solar constant and not just the visible light, the
entire spectrum of electromagnetic radiation is included in it.
• From the satellites, the solar constant is taken at the best direct
measurements. To calculate a solar constant, the Stefan-Boltzman
constant is used.
• In this case, the constant refers to the power per unit area emitted
by a black body as a function of its thermodynamic temperature.
5

6. 6
• The power of the Sun at the planet Earth as per square
meter is known as the solar constant and is approximately
1370 watts per square meter is denoted by W/m2.
• The constant that is the solar constant actually varies by
+/-3% because of the planet Earth's slightly elliptical orbit
around the star Sun.
• The distance between Sun-Earth is smaller when the Earth
is at perihelion that is the first week in January and larger
when the Earth is at aphelion that is the first week in July.
The Dimensional formula for
solar constant
• The solar constant is the
incident ray of solar energy
per unit area per second on
the earth surface.
• Solar constant = Energy /
(Unit area x Unit time)
= ML²T⁻² / (L²T)
= MT⁻³

7. 7
ESTIMATIONO
F SOLAR
RADIATION

8. 8
WHAT IS SOLAR
RADIATION?
• Electromagnetic radiation
emitted by sun.
• Solar radiation is the
energy emitted by the
Sun, which is sent in all
directions through space
as electromagnetic waves.
TYPES OF SOLAR RADIATION
• Direct solar radiation
• Diffuse solar radiation
• Global solar radiation

9. 9
ESTIMATION OF SOLAR RADIATION ON
HORIZONTAL PLANE
• Monthly average daily global radiation
• Monthly average daily diffuse radiation
• Monthly average hourly global radiation
• Monthly average hourly diffuse radiation
To estimate the amount of solar radiation falling on a solar collector at a
given time and location, the direct or beam radiation and diffuse
radiation should be either measured or estimation using empirical
equations.

10. 10
MONTHLY AVERAGE DAILY GLOBAL RADIATION
This is know as AUGSTROM CORRELATION.
Where,
Hg → monthly averaged daily global radiation on a horizontal surface
Hc → monthly averaged extra-terrestrial solar radiation at horizontal
surface (at top of atmosphere)
Sa → monthly average daily sunshine hours
Smax a → a maximum possible daily sunshine hours (the day length) at a
given location.
a and b → constant E
Hg Sa
Hc Smax a
= a + b