Qucestians

3.  Name of Candidates # Roll No
 SADAQAT ALI L-16EL-08
 (GROUP LEADER)
 RAZAQ WAHAB L-16EL-31
 (ASST.GROUP LEADER)
 MUHSIN RAZA L-16EL-63
 (MEMBER)
 KALTAR KUMAR L-16EL-06
 (MEMBER)
 BADAR-U-DDIN L-16EL-35
 (MEMBER)

5. CONTENTS
 Basics of Solar Energy
 Photovoltaic
 Solar Thermal system
 Economic Analysis
 Solar

6. INTRODUCTION
 Amount of energy in the form of heat and radiations from
sun called solar energy its natural source of energy
available in infinite. which is then used as ;
 solar pv technology, solar thermal energy, concentrated
solar power, molten salt power plant and solar heating..
 The amount of energy from the Sun that reaches Earth
annually is 4x1018 Joules.
 The amount of energy consumed annually by the world's
population is about 3 x1018 Joules.

8. Solar Radiations:
 The earth receives the solar energy in the form of solar radiation. These
radiations comprising of ultra-violet, visible and infrared radiation.
 Solar radiation are dependent on several factors like geographic location,
time of day, season, and scope and local weather.

9.  Solar Angles & Air Mass
 The earth is round, the sun rays strike the earth surface at different angles
(ranging from 0° to 90°). When sun rays are vertical, the earth’s surface gets
maximum possible energy.
 Air Mass is a measure of the amount of atmosphere the Sun’s rays have to pass
through.. The air mass coefficient is commonly used to characterize the
performance of solar cells under standardized conditions.

10. Photovoltaics
Photo+voltaic = convert light to electricity
Photovoltaic systems convert sunlight directly into electricity, and are
potentially one of the most useful of the renewable energy technologies.
Photovoltaic is the technology that generates direct current (DC) electrical
power measured in watt (W) or kilowatts (KW) from semiconductors when
they are illuminated by photons. As long as light is shining on the solar cell .

11. Solar Cells Background
 1839 - French physicist A. E. Becquerel first recognized the photovoltaic effect.
 1883 - first solar cell built, by Charles Fritts, coated semiconductor selenium with
an extremely thin layer of gold to form the junctions
 In 1918 Jan Czochralski, a Polish scientist, figured out a method to grow single-
crystal silicon. His discoveries laid the foundation for solar cells based on silicon.
 1954 - Bell Laboratories, experimenting with semiconductors, accidentally found
that silicon doped with certain impurities was very sensitive to light. Daryl Chapin,
Calvin Fuller and Gerald Pearson, invented the first practical device for converting
sunlight into useful electrical power. Resulted in the production of the first practical
solar cells with a sunlight energy conversion efficiency of around 6%.
 1958 - First spacecraft to use solar panels was US satellite Vanguard .
 In 1974 The Solar Energy Industries Association (SEIA) first forms, working to
promote, develop and implement the use of solar energy.
 In 1998 Inventor and scientist Subhendu Guha invents the first flexible thin-film
product.

12. Driven by Space Applications in
Early Days

13. PV Cell  solar cell whose size is approximately 6
inches long and 6 inches wide.
 A solar cell gives voltage of 0.5 V to
0.6 V.
 Most cells are made with Silicon,
Germanium, Gallium, Arsenide;
 A typical panel has 36 cells for about 21
V open-circuit (no current delivered)
but actually drops to ~16 V at max
power well suited to charging a nominal
12 V battery.

14. 14
Major Components in a typical PV installation
• PV Panels – solar cells
• Charge Controller
1. Match the panel voltage
and battery voltage
2. Extract maximum power
from the panel
3. Prevent over-charge
• Battery - Hold energy
• Inverter - convert DC to
60Hz AC for compatibility
with the power line voltage.
Ping Hsu

15. How Solar Cells Work
 Photons in sunlight hit the solar panel and are absorbed by semiconducting materials
to create electron hole pairs.
 Electrons (negatively charged) are knocked loose from their atoms, allowing them to
flow through the material to produce electricity.
p n
- +
- +
- +
- +
- +
hv > Eg

16. • Highly purified silicon (Si) from sand, quartz, etc. is “doped” with
intentional impurities at controlled concentrations to produce a p-n
junction
– p-n junctions are common and useful: diodes, CCDs, photodiodes, transistors
• A photon incident on the p-n junction liberates an electron
– photon disappears, any excess energy goes into kinetic energy of electron
(heat)
– electron wanders around drunkenly, and might stumble into “depletion
region” where electric field exists (electrons, being negative, move against
field arrows)
– electric field sweeps electron across the junction, constituting a current
– more photons  more electrons  more current  more power
16
Photovoltaic (PV) Scheme

17. PV Array
Components
oPV Cells
oModules
oArrays
•PV cells - Electricity is generated by PV cells, the smallest unit of a PV system
•Modules - PV cells are wired together to form modules which are usually a sealed, or
encapsulated, unit of convenient size for handling.
•Arrays – Groups of panels make up an array.

18. Factors Affecting Efficiency
• Angle of incidence of the sun
• Cloud cover
• Shading (even a small amount of shading
reduces output dramatically)
• Dirt, snow, or other impurities on cell surface
• Efficiency goes down as the cell gets hotter.
• Internal electrical resistance of the cell.
Ken Youssefi Introduction to Engineering – E10 18

19. 89.6% of 2007 Production
45.2% Single Crystal Si
42.2% Multi-crystal SI
• Limit efficiency 31%
• Single crystal silicon - 16-19%
efficiency
• Multi-crystal silicon - 14-15%
efficiency
• Best efficiency by SunPower Inc 22%
Silicon Cell Average Efficiency
First Generation
– Single Junction Silicon Cells

20. CdTe 4.7% & CIGS 0.5% of 2007 Production
 New materials and processes to improve efficiency
and reduce cost.
 Thin film cells use about 1% of the expensive
semiconductors compared to First Generation cells.
 CdTe – 8 – 11% efficiency (18% demonstrated)
 CIGS – 7-11% efficiency (20% demonstrated)
Second Generation
– Thin Film Cells

21.  Enhance poor electrical performance while maintaining very low
production costs.
 Current research is targeting conversion efficiencies of 30-60% while retaining
low cost materials and manufacturing techniques.
 Multi-junction cells – 30% efficiency (40-43% demonstrated)
Third Generation
– Multi-junction Cells

22. Future Generation
– Printable Cells
Organic Cell
Nanostructured Cell
Solution Processible Semiconductor

23. Interpenetrating Nanostructured Networks
-
metal electrode
transparent electrode
glass
+
- 100 nm
---
metal electrode
transparent electrode
glass
+
- 100 nm

24. Dye Sensitized Solar Cell

25. Solar thermal system
 Solar thermal technologies capture the heat energy from the
sun and use it for heating and/or the production of
electricity. This is different from photovoltaic solar panels,
which directly convert the sun’s radiation to electricity.
 Active systems require moving parts like fans or pumps to circulate
heat-carrying fluids. Passive systems have no mechanical components
and rely on design features only to capture heat. (e.g. greenhouses).
 Components of Solar Thermal Technology
 • Solar collectors
 • Primary and secondary circuits
 • Heat exchanger
 • Accumulator, pumps
 • Glass of expansion
 • Pipelines ,Main control panel.

26. ADVANTAGES
1. No Fuel Cost
3. No Pollution and Global Warming Effects
2. Predictable, 24/7 Power
Disadvantages
1.High Costs
2.Water Issue
3. Limited Locations and Size Limitations
4.Long Gestation Time Leading to Cost Overruns
5.Seasonal variation

27. Solar Thermal Application
 Swimming Pool Heating
 Solar Cooking (Ovens)
 Space Heating
 Solar Hot Water
 Solar Cooling
 Driers of agricultural products.

28. How much does it costs?
 Solar PV is usually priced in dollars per peak Watt
 or full-sun max capacity: how fast can it produce energy
 panels cost $2.50 per Watt (and falling), installed cost $5/W
 so a 3kW residential system is $15,000 to install
 State rebates and federal tax incentives can reduce cost
substantially
 so 3kW system can be < $10,000 to install
 To Plan a PV system
 Calculate total load
 Design a pv system double to that load
 Components cost (Batteries, Inverter,
panels,Controller.)

29. POTENTIAL OF SOLAR ENERGY IN PAKISTAN
 Pakistan has 2.9 million megawatts of solar energy potential.
 Pakistan spends about US$ 12 billion annually on the import
of crude oil. Of this, 70% oil is used in generating power
 Average monthly solar radiation intensity remains 136.05 to
287.36 W/m2.
 Pakistan's installed capacity is up to 33,836MW
 by February 2019 which stood at 23,337 MW in 2014,

31.  SINDH
 Solar radiation intensity remained 145.29 W/m2 (lowest) in December
in coastal areas and highest 331.27 W/m2 in central regions of Sindh
during June. Solar radiation intensity greater than 150 W/m2 was
observed throughout the province, except Rohri where intensity was
less than150 W/m2 in December. The radiation intensity greater than
200 W/m2 was observed from February to October in the province
except in northwestern parts and coastal areas of Sindh. Monthly
average solar radiation intensity remained from 162.44 to 299.31 W/m2
during the year.