International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor: 6.887
Volume 5 Issue VII, July 2017- Available at
Design & Manufacturing of Solar Panels
Cleaning System
Swanand S. Wable1, Somashekhar Ganiger2
PG Scholar, 2Assistant Professor , Department of Mechanical Engineering
JSPM’S Imperial College of Engineering & Research, Wagholi, Pune.
Abstract: The Solar Panels Farms are generally situated in dirt and dust areas which is mostly in case of tropical countries. The
performance of solar panels depends on various factors, the power generated by farm can decreased if there is dust and dirt on
panels and this is the main factor for reduction. One can generally assume a reduction of about 40% - 50%, if the panels are not
clean properly for 1-2 months. So to overcome this problem and to increase the efficiency of power production cleaning of
module on regular basis is necessary. To clean the dust, an automatic cleaning robot is developed, which will clean the panels on
regular interval of time. The mechanism is based on control circuit, DC motor; microfiber (bristles) to clean the panels. The
paper provides you with the idea how the robot will work and its effect on the energy production by solar farms. It will also to
help to understand the problem arise due to not cleaning of solar cells.
Keywords: Solar Panels, Energy loss, Design, Automatic Cleaning, Microcontroller.
The robots are alternative method to the conventional methods and they are design so to avoid the wastage of water and to reduce
the human effort to clean solar modules, but also labor-intensive, method of sending human workers to hose and wipe down panels
manually or use a truck-mounted sprayer to do so., Dirty panels produce less electricity, so to increase the production of electricity
cleaning of panels should be must, but the need to use water for cleaning those panels, especially in dry regions, makes even a clean
power project less eco-friendly. In certain remote corners, the water digged out from the ground is too brackish for use and also it
contains the corroded elements, if not being treated properly, due to this there is increase in production cost of a solar power plant.
In dusty areas such as the Middle East and India, solar panels
Could lose electricity production by 10 %to 35 % over time if
They are not washed on regular basis. Robots dry clean each panel and move from the top to the bottom of a row of panels. There is
increase in 2-3 % more electricity production than employing humans due to use of such robots, the challenge of
Keeping solar panels dust free will grow as more solar power projects are built worldwide. The cheap labor and plenty of water
supply will able to continue for making manual washing the low-cost choice for solar power plant owners.
The natural way to clean is air; air flow removes a bulk of the dust while the brushes get rid of the rest. So to avoid the wastage of
water, to reduce the human effort and time require cleaning the modules, a robot is developed which will help to clean the module
on regular interval of time, and also it will
overcome all the problems arise. The robot itself is a solar power charged but it will runs on two 12-volt lead-acid batteries at night.
Solar electricity recharges the batteries during the day. The robot will clean the panels to and fro on regular interval of time. After
completing its task the robot returns to a docking station and uses the rotational energy to get rid of the dust captured by the
microfiber. With about one year of field data of its robots’ performance, the startup projects that its equipment and services could
save 840 million liters of water for a 300 MW solar park over 20 years while increasing electricity sales by $180 million, Meller
said. How much the utilities are willing to pay for power.
Hence this paper will help to get an idea and innovative method of cleaning solar panels automatically.
In this paper you will find the idea of how the system will help you to clean the solar panels without the help of human & water,
thus saving the water usage. To do so various different kinds of research paper has been reviewed so that the concept should be clear
and the manufacturing of system should be easy. The need to clean the solar panels on regular basis is necessary because
accumulation of dust on panels reduces the intensity of incident rays, thus reducing its production efficiency. So periodic cleaning of
©IJRASET (UGC Approved Journal): All Rights are Reserved
International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887
Volume 5 Issue VII, July 2017- Available at
panels is necessary either manual or by automatic. With reference to this paper we have develop a new and easy technique to clean
the panels.
Various different methods are there for cleaning of panels like human using brush, spraying of water. But with the use of such
techniques we are wasting water as well as we are investing huge amount in cleaning. Cleaning is done everywhere. They have
design a robot which is human operated & thus it cannot work all the time as the panels should be cleaned after specific interval of
time. Hence there should be some automation done for better scope. [2]
The elements commonly required for cleaning the panels are water, human, brush, sprinklers. Sprinklers are used to sprinkle the
water in every side of panels.
This paper has given a better idea of making the robot without human. They have composed of a cleaning head that moves on panels
while the robot’s auxiliary equipment for power & water supply is connected via umbilical, located on an adjacent support vehicle.
The cleaning head is driven vertically by Cables & horizontally by a pair of motorized drive trolleys which rides along the bottom &
top edges of array panels. The drive and cleaning system needs to ensure the longevity of device. So design of new system is
necessary so that there will not be any complex in use and it will be fully automatic [1].
Cleaning the solar panels is normally by washing which is very tedious & cumbersome, at the same time its expensive too. The
design of auto cleaning robot will have flexibility in order to fix on different sizes of flat solar panels. In accordance with
dimensions of flat plate, the robot consists of rollers that will be driven by DC motors through belt system. The movements of
rollers will be controlled by microcontroller. In this they have used the external power for driving motor. It helps to reduce the labor
There is need of improvement in these conventional methods. An alternative to all these methods is to be found. There is a need to
achieve maximum efficiency by keeping the panels clean so that the rays can penetrate maximum amount of it on panels. [3]
Impact of progressive water-stains (scaling) on degrading the PV performance needs to be investigated including appropriate
mitigation measures. PV modules determine the nature of salt depositing/adhering to the glass surface, as the water used for
cleaning the panels contains a highly soluble salt which damages the panels. Such staining is particularly evident with bird dropping
and their subsequent cleaning. The impact of dust on the performance of solar collectors (including PV) has been attributed to the
immense solar potential, averaging nearly 6 kWh/m2/day in these regions combined with the susceptibility to a desert environment
(and frequent dust storms). There are many studies that confirm reduction of performance of producing energy by solar panels.
Consequently in order to produce and deliver the maximum amount of energy to the grid periodic cleaning of panels is necessary.
The dirt & dust cause highly effect on the performance of solar panels depends on various factors and always needs to be estimated
or evaluated for individual situations.
A. The Main Aim of the Project is
1) To maximize the energy production by solar panels in remote areas, in utility grade sites, in low expense and without impact on
manual and water used cleaning.
2) While cutting cost, the performance of photovoltaic panel in solar farms should be optimize.
The Major Factors Consider while Developing the System are
Robot should be compact in size; also it should be maintenance free.
It should clean the panels automatically without using water.
The material used for cleaning the solar farms should not damage the panels.
C. In Order to Overcome on above Problems following steps has been taken
1) Using a water-free microfiber and airflow cleaning system, it can be almost 99% dust free panels, and the production can be
2) The design should be easy to manufacture, low cost.
3) Design has been drawn in solid works for better understanding.
4) After analyzing all the calculations and design manufacturing has been done.
©IJRASET (UGC Approved Journal): All Rights are Reserved
International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887
Volume 5 Issue VII, July 2017- Available at
5) All major factors like climate, area of installation has been taken into consideration while designing.
A. Analysis of Dust on Solar Panels
The radiation reaching to the surface can decrease due to accumulation of dust on panels, thus decreasing the efficiency of solar
farms. The angle of incidence on the surfaces of modules changes due to dust. According to the research there is loss of about 4% 5% of energy daily. Test has been conducted for the energy losses due to red stain, dust, ash, sand etc, gives the different result.
Also the size of dust plays an important role in reduction of energy generation, more the size the less will be the generation of
energy. The drop of voltages and out power has been observed and shown in below graph:
Figure No.1. Effect of Dust on Power Production
B. The Main Components used are as follows
1) Microcontroller: There are about two microcontrollers which will help to control the to and fro movement of brushes. It will
also program in such a way that it will help the system to clean in a specific interval of time.
2) Brushes or Bristles: These are nylon bristles fitted on the roller to clean the solar panels. The roller will be fitted between the
two frames so that it can roll on the panels easily without any hindrance. It will roll throughout the panels, thus cleaning the
panels. The bristles fitted on the roller are microfibers type of number N-30 to 50micron.
3) Chain & Sprocket: The chain and sprocket mechanism is used to deliver the rotating power from motor to shaft. It is used as its
cheap and maintenance is also of very low cost compared to belt drive system.
4) Sensor: The sensors are used to sense the end and start of panels. It helps the robot to understand where to stop and where to
start. It’s also used to adjust the speed of shaft.
C. Design of all Mechanism Part
Material = C 45 (mild steel)
Considering factor of safety 1.5
Yield strength=280 N/mm2
Tensile stress= 140 N/mm2
1) Design of Motor:
Power of motor = 100 watt, 12V
Rpm of motor = 100 rpm
Calculation of power transmitted by shaft,
x motor efficiency (60%)
N=Rpm of motor
©IJRASET (UGC Approved Journal): All Rights are Reserved
International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887
Volume 5 Issue VII, July 2017- Available at
T=Torque transmitted
100 =
x 60%
T = 9.549 x 60% N-m
T = 9549.3 x 60% N-mm
T = 5729.58 N-mm
Motor is having inbuilt 1: 1.6 worm gear box
Torque & rpm obtain at gearing
No. of teeth (Motor), N1=15
No. of teeth (Sprocket), N2=24
So, Torque on sprocket =1.6 x T
= 1.6 x 5729.28
= 9167.32 N-mm
Speed of roller shaft = 100/1.6= 62.5 rpm
Now, Angular velocity (ω)of nylon brush,
= 0.575 m/s
So, Diameter of Sprocket,
Periphery= П x dia. of sprocket
Teeth x pitch= П x dia. of sprocket
24 x 6.25 = П x D
D= 47.74 mm
Now, Torque Transmitted,
T = Force x Radius
9167.32 = F x 23.8
F = 9167.32/23.8
F = 385.12 N
F = 39.25 kg
Now, Torque transmitted by shaft,
T = (П/16) x τ x D3
5729.58 = П/16 x 70 x D3
D = 7.47 mm.
Since, FOS = 1.5
Therefore, D = 7.47 x 1.5 = 11.2 mm
But we are using 20mm shaft, therefore our shaft
Design is safe.
For 20mm shaft diameter we take standard bearing
Number P204.
2) Design of Transverse Fillet Welded Joint on Shaft: We know,
Perimeter = П x diameter
= П x 20
= 62.83 mm
Selecting weld size = 3.2 mm
Area of weld = 0.707 x weld size x L
= 0.707 x 3.2 x П x 20= 142.15 mm2
©IJRASET (UGC Approved Journal): All Rights are Reserved
International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887
Volume 5 Issue VII, July 2017- Available at
Force Exerted = 40 x 9.81
= 392.4 N
Stress Induced = Forced exerted / Area of weld
= 392.4/142.15
= 2.76 N/mm2
For Filler weld:
Maximum Allowable Stress for welded joints = 210 kgf/cm2 = 21 N/mm2
Hence the welded joint is safe.
3) Design of Fillet Welded Joint: Hence, selecting weld size = 3.2mm
Area of weld = 0.707 x weld size x L
= 0.707 x 3.2 x П x 20
= 142.150 mm2
Force Exerted = 30 x 9.81
= 294.3 N
Stress Induced = Force exerted / area of weld
= 294.3/142.15
= 2.07 N/ mm2
For filler weld:
Maximum Allowable Stress for Weld Joints = 210 kgf/cm2 = 21 N/mm2
Hence Fillet welding done on plate is safe.
Now, Let the total weight (P) of our machine including solar panels be 200 kg, now this 200 kg weight is kept on four angle,
P = 200/4= 50 kg
P = 50 x 9.8
P = 490 N
Let, L = 500 mm
Therefore, M = WL/4
= 490 x 500/4
= 61250 N-mm
Now, Section of modulus, Z = (B2/6) – (b4/6) x B
= (402/6) – (254/6) x40
= 9039 mm2
Bending Stress = M/Z
= 61250/9039
= 6.776 N/ mm2
As induced bending stress is less then allowable bending stress i.e. 140 N/mm2, hence design is safe.
Power of Shaft, P = 25 Watt, 12V
Speed of shaft, N = 10 rpm
Power Transmitted by Shaft,
25 =
x Motor Efficiency
x 103 x 60%
T = 23.87 x 60% N-m
T = 2387.24 x 60% N-mm
T = 1432.39 N-mm
Now, Angular velocity (ω) of wheel,
©IJRASET (UGC Approved Journal): All Rights are Reserved
International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887
Volume 5 Issue VII, July 2017- Available at
= 0.0523 m/s
The main component of our machine is as shown in figure. We have to clean the solar panel by dry cleaning process, for that we are
using nylon brush of soft bristles so that it should not affect the transparency of solar panel in long term use. Now this brush will
rotate at high speed for throwing of the dust from the panel. The rotating motion for brush is given to it by motor mounted beside it,
the motor is of high rpm and low torque, so for balancing that chain sprocket is provided between then. This whole assembly is
mounted on the frame; the pedestal bearing is used for mounting rollers.
Figure No.2 Proposed Design
The frame with this assembly is mounted on four rollers; all four rollers are having individual motors of high torque and low rpm.
Below frame four idle rollers are also given for travelling smoothly on solar panel frame. We have used timer circuit in our machine
by which we can set how many times a day our machine will clean the solar panels. Our circuit is having only three press buttons
one will start the machine and other two will increase and decrease the time in seconds, which will be shown in display. On both the
ends of the machine limit switch is mounted which will stop the machine as it will go on the one end of the solar panel row.
Figure No.3 Proposed Model
©IJRASET (UGC Approved Journal): All Rights are Reserved
International Journal for Research in Applied Science & Engineering Technology (IJRASET)
ISSN: 2321-9653; IC Value: 45.98; SJ Impact Factor:6.887
Volume 5 Issue VII, July 2017- Available at
The Following are the Result Obtained after Analysing the Robot
Single robot for single row ( row length doesn’t matters)
Brush length can be adjusted according to panel width.
Timer is set on robot along with dust sensor( whichever is earlier)
Robot itself is solar powered.
Designed to run fully autonomous (No human is required)
Intelligent software control cleaning process.
There are some Benefits also which are stated as follows
Improvement in performance of solar system
Reduce cost of operations of solar plants
Extend lifetime of solar panels
Make solar power plants greener.
Dust accumulation on PV panels can significantly reduce their power output. While the Geographic region is solar-energy rich, the
desert conditions are quite dusty threatening the PV systems power generation potential. The robotic system proposed by me with
the help of company is a simple way to tackle this challenge effectively. Although promising results will be obtained. Here we are
going to set a new benchmark by using latest technology and replacing the conventional methods of cleaning the solar panels. We
are saving water, time and money. In general the technique used by other method explain above total cost of solar panel
maintenance goes around 5% of total plant cost annually but cleaning done by robot reduced it by 2%. The robot of this kind can
clean the solar farm as and when require very easily without man power thus saving the cost and waste age of water. Further we can
add very interesting features in our system like de-ionized water cleaning; camera for inspection and climate based cleaning. The
major advantage of this robot is that we can inspect the farm without going on actual site. Also in future we can reduce the weight
and can made compact design of the system with the help of booming technology. Also now a day there is increase in use of solar
system in industries as well as at homes, thus giving a bright future scope for this system.
I take this opportunity to thanks Prof S. G. Ganiger and Dr..S.H.Sarje for valuable guidance and for providing all the necessary
facilities, which were indispensable in completion of this work.
“Robotic Device for Cleaning Photovoltaic Panel Arrays” by mark Anderson, Ashton Grandy, Jeremy Hastie, Andrew Sweezey, Richard Ranky, Constantinos
[2] “Development of an automatic robotic cleaning system for photovoltaic plants”, by Nawaf Albaqawi and Alireza Gheitasi, Waikato Institite of Tecgnology,
New Zealand, 2014
[3] “Microcontroller Based Automatic Cleaning of Solar Panels” by S.B. Halbhavi, G. Kulkarni, Dr. D. B. Kulkarni, IJLTET Vol. 5 Issues 4th July,2015, ISN:
[4] “Effects of Dust on Performance of PV Panels” by Shaharin A. Sulaiman, Haizatul H. Hussain, NikSiti H. NikLeh, and Mohd S. I. Razali
[5] Gradual Reduction of energy production of pv plants through continuous soiling. Prof. Dr. H. Häberlin and Ch. Renken. University of Applied Science Bern.
University of Technology and Architecture Burgdor
[6] Salim, F. Huraib, and N. Eugenio, " PV power-study of system options and optimization," in Proceedings of the 8th European PV Solar, Energy Conference,
Florence, Italy, 1988.
[7] R. H. Hamid, F. El-Hussainy, M.M. Beheary, K. M. Abdel-Moneim, Energy Conversion and Management, 47, 3192 (2006).
[8] OSC Energy Inc., SolarWash, 7 Nov. 2008, .
[9] Denholm P, Drury E, Margolis R, Mehos M. Solar energy: the largest energy resource. In: Sioshansi FP, editor. Generating electricity in a carbon-constrained
world. California: Academic Press; 2010. p. 271–302.
[10] “Microcontroller Based Automatic Cleaning of Solar Panel” by S.B. Halbhavi, S.G. Kulkarnai,India
[11] Muhammad Jaradat, Yousuf Atlaf, Roba Saab, in “A FULLY PORTABLE ROBOT SYSTEM FOR CLEANING SOLAR PANELS” , UAE
[12] “Robotic Device for Cleaning Photovoltaic Panel Arrays” by mark Anderson, Ashton Grandy, Jeremy Hastie, Andrew Sweezey, Richard Ranky, Constantinos
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