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Effect of humidity on the efficiency of solar cell (photovoltaic)

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Manoj Kumar Panjwani at Sukkur Institute of Business Administration- North China Electric Power University
Manoj Kumar Panjwani
  • Sukkur Institute of Business Administration- North China Electric Power University
G.B. Narejo
G.B. Narejo
G.B. Narejo
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International Journal of Engineering Research and General Science Volume 2, Issue 4, June-July, 2014
ISSN 2091-2730
499 www.ijergs.org
Effect of Humidity on the Efficiency of Solar Cell (photovoltaic)
Manoj Kumar Panjwani 1, Dr. Ghous Bukshsh Narejo1
1Department of Electronic Engineering, NEDUET, Pakistan
E-mail- manoj_panjwani@hotmail.com
Abstract: Out of 100% energy coming from sun approximately 30% of the energy is either reflected back or is absorbed by clouds,
oceans and land masses. In cities where the humidity is more, like Karachi Mumbai, Malaga, Hamburg and Los Angles where in
average humidity ranges in (40-78 %), results in a minimal layer of water vapor at the front solar cell directly facing Sun. The Solar
energy which actually strikes the solar cell is subjected to loss in absorption/reflection of energy. There have been approximate losses
of about 15-30% of the energy in addition to 30%. One of the effects that we found out after our experimental analysis was of the
humidity that it brings down the utilization of solar energy approximately to 55-60% from just 70% approximately of utilized energy.
Keywords:Solar energy, humidity factor, absorption, effect, reflection, efficiency, approximation.
Introduction
If we talk about the energy which is received from Sun, Earth receives approximately of 1413 W/m2 and the actual consumption
which appears on the scale formulated is approximately 1050W/m2 as recorded by Pacific Northwest Forest and Range Experiment
Station Forest Service, U.S. Department of Agriculture, Portland, Oregon, USA in in 1972.As per the facts observed, approximately of
30% energy is lost in between. As per the statistical figures stated, that the Earth’s top of the atmosphere sunlight’s intensity is about
30% more intense than the actual received on the land. In the Solar panels what we use today, actually we make use of the 70% energy
coming from the Sun and utilize the working of our panels to fulfill our energy needs. [1-3]
As per the fact that the earth’s crust mainly consists of 70% of Water, the energy which strikes the earth is indirectly striking the
water/oceans which helps in increasing of humidity level on the overall basis. The humidity doesn’t only create hurdles for the energy
actually received at the top of the atmosphere but also effects the device consumptions by many aspects.[4-5]
The aspects what we covered is the effect of humidity on the Solar panels which create obstacles for drastic variation in the power
generated , indirectly making the device work less efficient than it could have without it. The cities where in the humidity level is
above the average range of 30 actually results in the minimal layer of water on the top of the Solar panel which results in decreasing of
the efficiency.
As per the facts when the light consisting of energy/Photon strikes the water layer which in fact is denser, Refraction appears which
results in decreasing of intensity of the light which in fact appears the root cause of decreasing of efficiency. Additional there appears
minimum components of Reflection which also appears on the site and in that, there appears light striking is subjected to more losses
which after the experiments conducted resulted approximately in 30% loss of the total energy which is not subjected to utilization of
Energy for the Solar panel.[6]
AS far as the efficiency of the Solar cell is concerned, Efficiency is termed as the amount of the light that can be converted into usable
format of electricity. Because of the efficiency depends upon the value of Maximum Power Point of the Solar cell , due to the above
effect of humidity ,the maximum power point is deviated and that indirectly results in decreasing of the Solar cell Efficiency.[7-8]
Interesting facts appears to provide surprising figures about the population in Coastal areas around the globe. According to National
Oceanic and Atmospheric Administration USA, about 52% of the Population in USA lives coastal counties Los angles, Texas, Calif
Etc. [9]
According to the top world users of Solar Energy ,Germany(9785MW),Spain(3386MW), Japan(2633MW) and USA(1650) appears to
dominate among the users of Solar Energy and where in the coastal humidity ranges among the cities as Hamburg(Germany) as 50-
70% , Malaga(Spain) as 65-80%,Tokyo(Japan) 45-65% and Log angles (USA) as 70-95%.[10]
International Journal of Engineering Research and General Science Volume 2, Issue 4, June-July, 2014
ISSN 2091-2730
500 www.ijergs.org
The usage of the Solar Panel is readily effected by the effect of humidity and the values corresponds to change is the humidity is
subjected to change
Experiment and Analysis:
Various experiments were conducted and in the test bench included 50W BP Solar Panel having specification of Vamp = 17.3V and
Imp = 2.9A with temperature coefficient of Isc= (0.065 ± 0.015) % / °C, Temperature coefficient of Voc=-(80 ± 10) mv / °C and
Temperature coefficient of power=-(0.5 ± 0.05) % / °C, and Tungsten Halogen Bulb of 1000W, 2 Humidifier, Hygrometer,
Thermometer, Output Load as tungsten filament bulbs(15,20,25W) , 2 Millimeters.
Results were calculated initially with normal temperature in Karachi which was 32*C (305K) and humidity 25.The humidifier was
used as to increase the humidity level of the area where in the Solar panel was connected with the load and was subjected to a constant
intensity by using tungsten Halogen bulb and the distance was kept 2 foot. The readings were noted and the humidity was carefully
calculated by the use of Hygrometer.
The results showed the drastic change in the readings when the humidity was subject to gradually increase. Below is the chart in
where the readings are noted
Temperature(K)
Humidity (%)
Voltage (DC)
Current Amps(DC)
Powers(watts)
305
25
17.10
2.78
47.538
305
30
16.72
2.63
43.973
305
35
16.53
2.42
40.002
305
40
16.45
2.3
37.605
305
45
16.41
2.14
35.117
305
50
16.33
2.04
33.313
305
55
16.32
1.88
30.681
Table 1: Humidity vs. voltage, current and power readings taken through the experimental set up as discussed.
Below are the graphs where in the relation between Humidity to voltage, current and power are calculated
International Journal of Engineering Research and General Science Volume 2, Issue 4, June-July, 2014
ISSN 2091-2730
501 www.ijergs.org
Fig1. Graph between Humidity and Voltage. Humidity appears as X axis and Voltage appears at Y axis
. Graph between Humidity and Current. Humidity appears as X axis and Current appears at Y axis
16.2
16.3
16.4
16.5
16.6
16.7
16.8
16.9
17
17.1
17.2
010 20 30 40 50 60
Humidity vs. Voltage
Voltage
0
0.5
1
1.5
2
2.5
3
010 20 30 40 50 60
Humdidty Vs. Current
Current
International Journal of Engineering Research and General Science Volume 2, Issue 4, June-July, 2014
ISSN 2091-2730
502 www.ijergs.org
Fig3. Graph between Humidity and Power. Humidity appears as X axis and Power appears at Y axis
After the results which are obtained so far , the readings clearly shows that the humidity level do effect the working of the solar panel
and can drag down the efficiency of the Solar panel is installed in cities where in the normal humidity level appear more.
Percent Reduction in Power =(P (Without Humidity)-P (with Humidity))/P (Without Humidity)*100
5% Humidity Increased
1st= ((47.538-43.973)/47.538)*100=7.499% Approx.
10% Humidity Increased
2nd= ((47.538-40.002)/47.538)*100=15.85% Approx.
15% Humidity Increased
3rd = ((47.538-37.605)/47.538)*100=20.89% Approx.
20% Humidity Increased
4th= ((47.538-35.117)/47.538)*100=26% Approx.
25% Humidity Increased
5th= ((47.538-33.313)/47.538)*100=29.92% Approx
Acknowledgment
I would like to thank Dr.Lachhman Das Dhomeja, Professor at Institute of Information and Communication Technology, University of
Sindh , Indra Devi Sewani , PHD Student at Sindh University Jamshoro and Radha Mohanlal , Lab Engineer at IOBM for being
Humidity vs. Power
Power
International Journal of Engineering Research and General Science Volume 2, Issue 4, June-July, 2014
ISSN 2091-2730
503 www.ijergs.org
supportive and informative in my goals and for unconditional help without which this task submission of Research wouldn’t have
been ever possible
CONCLUSION
After the experiments conducted, humidity drastically effect the performance of the Solar Panel and proves out to decrease the Power
produced from the Solar Panels up to 15-30% if subjected to environment where in the Humidity level remains high
Future Prospects and Suggestions:
After observing such a drastic change when it comes to change in humidity level , the required Solar Panels should be designed in
such a way specially in Pakistan which could be made to have less effects of humidity level on the Power ratings.
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Zeller, P., Libati, H.M.Utilization of solar energy for electrical power supply in rural African areas, Nairobi 2009
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... Finally, authors Manoj and Dr. Ghous Bukshsh Narejo, calculate the Percent Reduction in Power, about increased every 5% in humidity, decreased by approximately 6% of power. [13] Valentine, Chigozie, and Godswill articles, [12] they took another experiment to prove that lower humidity higher efficiency of solar panels. One solar panel was placed in a fixed position, and the solar temperature and solar flux changed as the humidity levels changed. ...
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  • SOL ENERG MAT SOL C
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An efficient method of Solar Panel Energy Measurement System
  • Jan 2009
  • G Mustafa
  • F Khan
Mustafa, G. ; Khan F, "An efficient method of Solar Panel Energy Measurement System", Dhaka 2009 nancyschuelke.hubpages, Top-5-Users-of-Solar-Energy-In-the-World.
Energy and energy analysis of solar photovoltaic system Advanced solar panel designs
  • Jan 2006
  • Ravi Prakash Tiwari
  • M Rajesh
  • K Sudhakar Bhopal Ralph
  • E L Linder
Ravi Prakash Tiwari, Rajesh M, K. Sudhakar" Energy and energy analysis of solar photovoltaic system", 2012 Bhopal Ralph, E.L., Linder, E.B. Advanced solar panel designs, Washington, DC 2006.
Design and proper sizing of solar energy schemes for electricity production in Malaysia
  • Jan 2003
  • P Zeller
  • H M Libati
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