Oro551 res- unit 1 - extra terrestrial and terrestrial solar radiation

1. ORO551 - RENEWABLE ENERGY SOURCES
M.KARTHIKEYAN
ASSISTANT PROFESSOR
DEPARTMENT OF MECHANICAL ENGINEERING
AAA COLLEGE OF ENGINEERING & TECHNOLOGY, SIVAKASI
karthikeyan@aaacet.ac.in
8825676616M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

2. 1. Role and potential of new and renewable source.
2. The solar energy option.
3. Environmental impact of solar power.
4. Physics of the sun.
5. The solar constant.
6. Extraterrestrial and terrestrial solar radiation.
7. Solar radiation on titled surface.
8. Instruments for measuring solar radiation and sun shine.
9. Solar radiation data.
UNIT I PRINCIPLES OF SOLAR RADIATION
M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

3.  The energy produced and radiated by the sun is called solar energy.
 Energy is radiated by the sun as electromagnetic waves.
 Wavelength range = 0.2 to 4 micrometer.
 The energy from the sun reaching the top of the earth’s atmosphere
consists of
 Ultra violet radiation = 8% [less than 0.39 micrometer]
 Visible light = 46% [0.39 to 0.78 micrometer]
 Infra red radiation = 46% [more than 0.78 micrometer]
M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI
INTRODUCTION

4. M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI
EXTRATERRESTRIAL / TERRESTRIAL SOLAR RADIATION

5. M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

6. 1. DIRECT RADIATION: Solar radiation that reaches to the surface of
earth without being diffused is called direct beam radiation.
2. DIFFUSED RADIATION: As sunlight passes through the
atmosphere, some of it is absorbed, scattered and reflected by
air molecules, water vapour, cloud, dust, and pollutants from power
plants, forest fires, and volcanoes. This is called diffused radiation.
3. GLOBAL SOLAR RADIATION: The sum of diffuse and direct solar
radiation is called global solar radiation.
4. REFLECTED RADIATION: It is the amount of solar
energy reflected from a surface
M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

7. M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

8. M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

9. EXTRATERRESTRIAL SOLAR RADIATION:
1. Solar radiation incident on the outer atmosphere of the earth is
called extraterrestrial radiation.
2. On average the extraterrestrial irradiance is 1367 (W/m2).
M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI

10. TERRESTRIAL SOLAR RADIATION:
1. Solar radiation that reaches the earth surface after passing
through the earth’s atmosphere is known as terrestrial solar
radiation.
2. Hence terrestrial solar radiation is always less than the
extraterrestrial solar radiation.
3. This reduction in intensity is due to
 Atmospheric absorption
 Scattering etc.,
M.KARTHIKEYAN AP/MECH AAACET
SIVAKASI