1. Submitted by:
Pritam Rath
Regd No: 0911013206
Electrical Engineering
Guided By:
Mr. Manas Ranjan Nayak
Assistant Professor
Department of Electrical Engineering
ITER, BHUBANESWAR

2. Present and Future
Efficiency Analysis
Triple Junction Tandem Solar Cells
Solar Cells
How to Harness Solar Power
Solar Energy – An Overview

3.  The output of sun is
2.8 1023KWH/year. The
energy reaching the earth is
1.5 1018KWH/year.
 Solar energy technologies
include solar heating, solar
photovoltaics, Solar air
conditioning, Solar lamp, Space-
based solar power.

5. P
N
P
N
Solar Power is converted to
electricity using PV
(Photovoltaic) effect.Solar Power is concentrated
and converted to thermal
energy which is converted to
electric energy.

6. Triple Junction
based High
Efficiency Tandem
Solar Cells

7. In 1839, Edmond Becquerel found that two different brass plates
immersed in a liquid produced a continuous current when
illuminated with sunlight. We now believe that he had made a
copper - cuprous oxide thin - film solar cell. Later in the
1870s, Willoughby Smith, W. G. Adams, and R. E. Day
discovered a PV effect in selenium.
A solar cell is a semi-conducting device made of silicon or other
materials, which, when exposed to sunlight, generates electricity.
It uses the Photovoltaic technology.

10. Mono-Crystalline
silicon cells
Poly Crystalline Solar
Cells
Thin Film Solar Cells
Multi-junction Solar
Cells

11. Triple Junction
based High
Efficiency Tandem
Solar Cells

13. Si
Si
Si
Si
Si
Valence Band
Forbidden
Band Gap
Ev
Ec
SILICON STRUCTURE
Energy
Conduction Band

14. As
33
In
49
Ga
31
Electron
without bonding
GaInAs STRUCTURE

15. Conduction Band
Valence Band
Forbidden
Band Gap
Ev
Ec
Energy
Valence Band
Ev
Ec
EfEnergy
Band
Gap
SILICON GaInAs
Conduction Band

16. Triple Junction
based High
Efficiency Tandem
Solar Cells

18.  The efficiency in recent years have been 60%
in satellites and nearly 85% in laboratory for
30cm2 cell at 200 suns.
 As compared to its counter parts such as other
silicon solar cells having efficiency nearly
20%.
 The most important factor is the end-of-life
(EOL) efficiency.

20.  Presently this kind of Solar cell technology is only
restricted to space applications.
 All the Satellites use this kind of Solar Cells.
 The main hindrance in the commercialization of this
kind of solar cell is the cost.
 Cost of these solar cells is $2.48/cm2.
 Lots of research work is going on to reduce the price.

21.  T. Takamoto, K. Sasaki et al., Proceedings of the 35th
IEEE Photovoltaic Specialists Conference, Hawaii, USA,
June 2010.
 Research and Development Trends of Solar Cell for
Highly Efficiency daisuke kanama, hiroshi kawamoto
Nanotechnology and Materials Research Unit, quarterly
review no.28/july 2008.
 Martin A. Green, Keith Emery, Yoshihiro Hishikawa and
Wilhelm Warta, “Solar cell efficiency tables”, Published
online 18 June 2010 in Wiley InterScience
(www.interscience.wiley.com). DOI: 10.1002/pip.1021.