The document is a presentation on solar cells, covering topics such as their introduction, history, construction, power storage, classification, applications, and future prospects. It explains how solar cells convert sunlight into electricity, their efficiency, and the importance of energy storage, alongside the challenges like cost and geographical requirements. The presentation concludes that solar energy is an environmentally friendly solution to energy crises with potential for widespread adoption in the future.

1. z
OUR TOPIC IS
SOLAR CELL
WELCOME TO THE PRESENTATION
PRESENTED BY
KRISHNENDU KARMAKAR(L-12)
SUJOY MUKHERJEE(L-02)
DEPT.– ECE, 3RD YEAR, 6TH SEM
KALYANI GOVT. ENGG. COLLEGE

2. z OVERVIEW
1.INTRODUCTION
2.HISTORY
3. CONSTRUCTIONS
4.POWER STORAGE
&
POWER CONTROL
5.CLASSIFICATION
6.APPLICATION
7.FUTURE PROSPECT
8.CONCLUSION

3. z
SOLAR CELL INTRODUCTION
 Semi conductor device.
 Converts electromagnetic radiation into
electrical signals, basically generates electricity
from direct sunlight radiation, known as
photovoltaic cell.
 To generate desired power, we connect
number cells together and form solar panel.
 the number and size depends on demand of
power and available sunlight.

4. z
HISTORY
1954
1994
BELL LAB announces the invention of 1st solar cell
with 6% conversion efficiency.
NREL(National Renewable Energy Laboratory,
spectrolab) developed 2-terminal concentrator
cell with 30% conversion efficiency.

5. z
CONSTRUCTION
 Light enter through an optical coating that
minimizes the loss of light by reflection, traps the
solar radiation made of titanium formed on cell
surface by vacuum disposition technique.
 After light passes the surface enters core layer
that consists of P-N junction diode made of silicon
in which electrons and holes are generated by the
incident photons.
 Light generate voltage across P-N junction
excites electrons and holes in it to start moving
across junction if battery is connected with it in
forward bias.
 Current flow caused by light known as light
light generated current (IL),there is large drift
current due to minority carriers and a diffusion
current (Io) also present flows opposite to IL.
Itotal = Io – (eqv/kt - 1) - IL
 The material used for junction must be
dissimilar to absorber in order to produce built in
electric field with large area because power
produced proportional to illuminated area.Solar cell circuit diagram

6. Solar cell V-I characteristics

7. z POWER STORAGE
 Solar cells works on during the presence of sunlight
so at night time when sunlight is absent we need to
store the energy for our work.
 To save solar energy , several solar cells are mounted on
a common panel connected in series or parallel for
increasing the voltage or power respectively . This type
of structure is called solar panel connected to battery.
 In this type of system the usual choice for energy storage
is lead-acid battery.
 Solar batteries work by storing the DC energy being produced by your solar panels and it can
also store energy as AC power for later use by inverter. The higher your battery's capacity, the
more solar energy it can store.
 Solar battery able to store excess solar electricity by charging the battery and solar panels are
not working we can draw energy from it for night use, if the battery fully charged then we
send it to grid and use it when battery is depleted.
 Maximum efficiency is solar cell so far now 44.5% but current using solar technology converts
electricity with 25%.

8. POWER CONTROL
 The battery will be damaged if it is allowed to be overcharged or over discharged, so a controller
needed to protect it.
 Smallest systems may have been only a few 12 volts lights, but in bigger systems 230 volts will
probably needed.
 An inverter is used to transform the low
voltage DC generated by the solar panels
into mains AC voltage.
 The power output is maximum for a
particular load resistance.
 The output voltage increases with increasing
in light intensity but beyond a certain intensity
the output voltage remain constant.
 The efficiency of solar is defined as the ratio of electrical output to amount of input solar enegy
produced by the solar cell.

9. z
CLASSIFICATION OF SOLAR CELLS
14%-17% efficiency 13%-15% efficiency 5%-7% efficiency

10. APPLICATION
 HOME POWER SERVICE  ELECTRICAL POWER GENERATION
IN SPACE
 ELECTRICAL POWER STATION  SOLAR POWER CAR
 OTHERS: DOMESTIC POWER SUPPLY, WATER PUMPING STATION AND
TELECOMMUNICATION SYSTEM etc.

11. z
FUTURE PROSPECT
ADVANTAGE
 Renewable energy .
 Clean and Non polluting.
 Innovative.
 Require very little maintenance.
 No supply problem, long life
time.
DISADVANTAGE
 Very expensive at present time.
 Cant be obtained in night time.
 Large free geographical area
needed for high amount of power
generation.
 Weather disturbance.
Name of some famous solar cell manufacturing companies –
SunPower, LG, Panasonic, Solartech universal, Silfab etc.

12. FUTURE PROSPECT
 In future solar cells and solar powered device will be seen every where.
 We will see solar cell notebook, artificial leaf to perform photosynthesis,
solar glasses, ultra-thin concrete roof to generate solar power etc.

13. CONCLUSION
 As it is a environment friendly energy source will reduce environment pollution.
 It will become the most cost-efficient energy source in near future.
 High use of solar cells will decrease green house gas emissions.
 It is a perfect solution for our energy crisis.
Bibliography
o Modelling on solar cells by Balaji Padmanabhan taken
from www.nanohub.org
o World’s Most Efficient Solar cell journal from
www.nrel.gov>news>press
o Solar cell nature materials from www.nature.com
o Solar cell history www.popsci.com/article/science

14. ANY
QUESTIONS ?