ARUSHA TECHNICAL COLLEGE
JUNCTION OF MOSHI-ARUSHA AND NAIROBI ROADS
P.O. BOX 296, ARUSHA-TANZANIA
TELEPHONE: +255-27-2503040/2502076, FAX: +255-27-2548337
WEBSITE: http://www.atc.ac.tz, E-MAIL: rector@atc.ac.tz
ELECTRICAL ENGINEERING DEPARTMENT
ORDINARY DIPLOMA IN ELECTRICAL ENGINEERING
FINAL YEAR PROJECT– 2020/2021
PROJECT TITLE: SOLAR TRACKER SYSTEM
PRESENTED BY: SIMPLISI PRISCUS SHAO
ADMISSION No: 18030712017
NTA LEVEL 06
ACADEMIC YEAR 2020/2021
1
DECLARATION
I SIMPLISI PRISCUS SHAO, hereby declare that the work submitted for the project SOLAR
TRACKER SYSTEM is my original work. I have not copied from any other student’s work or
from any other sources except where due reference or acknowledgment is made explicitly, nor
has been authored by another person.
Name: SIMPLISI PRISCUS SHAO.
Date submitted:
Received for examination by Sir. DANIEL MAYALA.
Date:
i
ABSTRACT
The goal of this thesis was to develop a laboratory prototype of a solar tracking system, which is
able to enhance the performance of the photovoltaic modules in a solar energy system. The
operating principle of the device is to keep the photovoltaic modules constantly aligned with the
sunbeams, which maximizes the exposure of solar panel to the Sun’s radiation. As a result, more
output power can be produced by the solar panel.
The work of the project included hardware design and implementation, together with software
programming for the microcontroller unit of the solar tracker. The system utilized an
ATmega328P microcontroller to control motion of two servo motors, which rotate solar panel in
two axes. The amount of rotation was determined by the microcontroller, based on inputs
retrieved from four photo sensors located next to solar panel.
At the end of the project, a functional solar tracking system was designed and implemented. It
was able to keep the solar panel aligned with the sun, or any light source repetitively. Design of
the solar tracker from this project is also a reference and a starting point for the development of
more advanced systems in the future.
ii
ACKNOWLEDGEMENT
I would like to express my heartfelt gratitude to Sir. DANIEL MAYALA, who is my supervisor,
for his constant guidance in the implementation of this project.
I must particularly thank him for commitment and unrelenting effort to see I do all the
assignment appertaining to this project and finally I can say I had done.
Thank you.
iii
TABLE OF CONTENTS
DECLARATION............................................................................................................................ i
ABSTRACT .................................................................................................................................... ii
ACKNOWLEDGEMENT ............................................................................................................. iii
TABLE OF CONTENTS ............................................................................................................... iv
TABLE OF FIGURES ................................................................................................................... vi
LIST OF TABLES ........................................................................................................................ vii
CHAPTER ONE ............................................................................................................................. 1
1. INTRODUCTION ...................................................................................................................... 1
1.1General Background ............................................................................................................... 1
1.2 Problem statement ................................................................................................................. 1
1.3 Problem justification ............................................................................................................. 2
1.4. Objectives ............................................................................................................................. 2
1.4.1. Main objective ............................................................................................................... 2
1.4.2 Specific objectives .......................................................................................................... 2
1.5. Significance of the project.................................................................................................... 2
1.6. Scope of the project .............................................................................................................. 3
CHAPTER TWO ............................................................................................................................ 4
2.0 LITERATURE REVIEW ......................................................................................................... 4
2.1 Introduction ........................................................................................................................... 4
2.2Existing system ...................................................................................................................... 4
2.2.1 Block diagram of stationary solar tracker....................................................................... 5
2.2.2 Block diagram of single axis solar tracker ..................................................................... 5
2.3 Drawbacks of the existing system ......................................................................................... 6
2.4 Proposed system .................................................................................................................... 6
iv
2.4.1 Working principle ........................................................................................................... 6
2.4.2 Block diagram of the proposed system........................................................................... 7
2.5Advantages of the proposed system ....................................................................................... 7
CHAPTER THREE ........................................................................................................................ 8
3.0 METHODOLOGY ................................................................................................................... 8
3.1 Literature review ................................................................................................................... 8
3.2 Data collection....................................................................................................................... 8
.3.3 Data analysis ........................................................................................................................ 8
3.4 Designing .............................................................................................................................. 8
3.5 Circuit implementation and testing ....................................................................................... 8
3.6 Project report writing ............................................................................................................ 8
3.7Simulation .............................................................................................................................. 9
CHAPTER FOUR ......................................................................................................................... 11
4.0 DATA COLLECTION ........................................................................................................... 11
4.1 Data Collection Methods..................................................................................................... 11
4.1.1 Primary Data Collection ............................................................................................... 11
4.1.2 Secondary data collection. ............................................................................................ 11
CHAPTER FIVE ................................................................ Ошибка! Закладка не определена.
5.0 DATA ANALYSIS ............................................................................................................. 13
REFERENCE ................................................................................................................................ 18
v
TABLE OF FIGURES
Figure 1 block diagram of stationary solar tracker ......................................................................... 5
Figure 2 Block diagram of single axis solar tracker ....................................................................... 5
Figure 3 Block diagram of dual axis solar tracker .......................................................................... 7
vi
LIST OF TABLES
Table 1 Project timeline .................................................................................................................. 9
Table 2 Cost estimation of the project. ......................................................................................... 10
vii
CHAPTER ONE
1. INTRODUCTION
1.1General Background
Today’s world has increasing demands for energy by the day especially in Tanzania
industrialization, which is against the continuous reduction in existing resources of fossils fuels
and ever growing concern regarding environmental pollution. It’s therefore needless to say that
this has pushed mankind to explore new technologies for production of electrical energy, using
clean, renewable sources such as solar and wind power.
A prominent non-convectional renewable energy source is solar energy which provides great
prospect for conversion into electrical power, which in turn ensures an important part of the
electrical energy needs of the planet.
Photo-voltaic (PV for short) is the conversion principle employed in conversion of solar light
into electricity. Using solar tracking technique, yield from solar panel can be increased by 30% 60% unlike in stationary or fixed installations which if we assume silicon is the material used to
build the PV panels, then the system is only about 24.5% efficient. [1]
1.2 Problem statement
There are many problems that occur in the previous type of solar tracking systems especially in
my society. The problem here is the solar that is use only the fixed installation and single axis
solar tracker. Because of this problem, the power that can be generated is low. The other is the
price of the solar tracking system is very expensive for the family that use more power than usual
because its need to install more than one solar panel to produce enough power. So this project is
to fix the problem that occurs. This solar panel can detect a 180 degree of rotation in both
directions, horizontally and vertically. [2]
The other problem is related with solar energy. The fixed solar panels or single axis solar panels
do not aimed directly to the sun due to the constant motion of the earth. As the result the power
produced by this device is not maximum as it should produce. The better solution for this system
to get the maximum output power is through dual axis solar tracking. This is the reason main
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reason why the dual solar tracker is made. The solar tracker will follow the sunlight to get more
output power. Indirectly it will reduce the cost of buying more solar panels. These systems also
reduce the time for users to change the position of solar panel to face the sun.
1.3 Problem justification
The aim of this project is to ensure that sunlight rays are falling perpendicularly on the solar
panel to give the maximum solar energy which is harnessed into electrical power with the
maximum energy being between the period of 1200Hrs to 1200Hrs with the peak around midday
when the sun is almost directly above the solar panel and so maximum energy is used to move
the solar panel, further increasing the efficiency of the tracker. This project seeks to address the
challenge of accurate, low power as well as economical micro-controller based solar tracking
system that can be implemented using the allocated time and resources so as to track the relative
motion of the sun in the sky during daylight and to save the much needed power, sleep at night.
An algorithm is implemented to solve the problem of motor control which is then written in into
Arduino IDE software.
1.4. Objectives
Objectives are specified into two groups namely, these are as follows;
1.4.1. Main objective
To design a system to track solar ultra-violent light for solar panels to track the sun light from
both directions i.e. horizontal and vertical
1.4.2 Specific objectives
•
To study the existing system and analyzing where to makes a modifications
•
To modify or addition of new features on the existing system
•
To design the circuit simulation by using software i.e. Arduino IDE, proetus 8
professional.
•
To develop a project and testing the designed system.
1.5. Significance of the project

Two or dual-axis tracking solar tracker have a double angle of rotation horizontal to each
other.
2

It tracks the solar radiation in both two directions, east-west (E-W) and north-south (NS).

It has the advantages over single axis since it can track the sun in both horizontal and
vertical directions.
1.6. Scope of the project
This project focuses on constructing a model mechanism which allows a solar panel to be able to
follow a light source. In this project, the scope has been reduced due to time and resource
limitations. Because of this, only a small scale version of the tracking solar panel will be built as
a basis for the data collection. Due to the smaller area of the solar panel, this will limit the
amount of electricity that can be generated, which is something that has to be considered when
discussing the results of the project. The small size of the solar panel and the other involved parts
also means that the structure will not be subjected to big loads. Therefore, there will not be any
major calculations for the strength of the structure. As a continuation for the project, a full-scale
version could be built. For a full-scale version of the structure, strength calculations would have
to be made. This project will only examine the amount of energy that is produced by the solar
panels, and not how much energy is needed to power the mechanism. This is also something that
can be examined in future work. Reliability and required maintenance are important issues, but
this is also something that will not be examined during the project.
3
CHAPTER TWO
2.0 LITERATURE REVIEW
2.1 Introduction
Among the renewable energy sources in electrical solar energy from the sun can be harnessed
using solar panels or solar cells to convert solar irradiation into electrical current.
Most photo-voltaic cells employ photoelectric effect. This is a process by which electrons are
emitted from some materials, such as a metal, as a result of being stuck by photons. Some
substances such as selenium, are particularly susceptible to this effect and if used in solar cells,
they can generate some electric potential through photo emission.
Sun rays come in form of ultra-violent light, a form of electromagnetic radiation and once they
fall of solar panel surface made of materials such a silicon, the irradiation is absorbed and
converted into electrical energy through photo emission. Maximum absorption occurs when the
solar panel and solar cells directly face the sun, so that the sun’s rays fall perpendicularly on the
absorption surface. [3]
This absorption and conversion may not be optimal given that the solar panels and solar cells are
mounted in fixed positions usually on rooftops with slants.
For viable solar energy generation using single installation, its efficiency has to be improved and
therefore various solar tracking methods are devised to closely track sun movement during the
day.
2.2Existing system
While solar panels are an effective means of collecting energy, their efficiency at doing
so is directly related to their angle with the sun. Because Photovoltaic cells get the most energy
from facing the sun, a stationary solar panel collects less sunlight.
Here in Tanzania most of the solar systems are either stationary solar tracker or single
axis solar tracker which are usually made depending on a single horizontal or vertical axis. The
direction of the axis is decided based on the location where system is going to be placed, the
location plays a role in the sun position during the day along with how much daylight is there. So
4
the amount of output power will be less since the panels they can only tracking sunrays from the
fixed position or from single axis, either (North-South) or (East-West). [4]
2.2.1 Block diagram of stationary solar tracker
Figure 1 block diagram of stationary solar tracker
2.2.2 Block diagram of single axis solar tracker
POWER
SUPPLY
LDR
SERVO MOTORS
PROCESSIN
G UNIT
MOTOR
DRIVER
Figure 2 Block diagram of single axis solar tracker
5
SOLAR
PANEL
2.3 Drawbacks of the existing system
1. The problem that this project addresses is the inefficiency associated with fixed solar
panels or single axis panel.
2. Fixed solar panels do not track effectively the sun across the sky.
3. They can be very expensive since there is need of many panels so us to obtain the high
output voltage
2.4 Proposed system
While solar panels are an effective means of collecting energy, their efficiency at doing
so is directly related to their angle with the sun. In this projects include design and construction
of an Arduino based solar tracker which will be able to track the sun light from both directions
and dual axes. This solar tracker system uses the Arduino board, a servomotor, 2 LDR and 2
resistors to rotate the solar panel towards the sun or a source of light. This panel tracker will be
moving in both directions depends on the sun position (180 degrees vertically and 360 degrees
horizontally). In this project LDR was selected since it has no polarity, and easy to interface with
circuit, cheap, reliable and is described by high spectral sensitivity, so that difference in high
intensity is represented immediately by change in its resistance value. [8]
2.4.1 Working principle
1. Resistance of LDR depends on intensity of the light and it varies according to it. The
higher is the intensity of light, lower will be the LDR resistance and due to this the output
voltage lowers and when the light intensity is low, higher will be the LDR resistance and
thus higher output voltage is obtained.
2. A potential divider circuit is used to get the output voltage from the sensors
3. The LDR senses the analog input in voltages between 0 to 5 volts and provides a digital
number at the output which generally ranges from 0 to 1023.
4. Now this will give feedback to the microcontroller using the Arduino software (IDE).
5. The servo motor position can be controlled by this mechanism which is discussed later in
the hardware model.
6. The sensitivity of the LDR depends on point source of light. It hardly shows any effect on
diffuse lighting condition.
6
2.4.2 Block diagram of the proposed system
Figure 3 Block diagram of dual axis solar tracker
2.5Advantages of the proposed system
1. This system (two or dual-axis tracking solar tracker) have a double angle of rotation
horizontal to each other.
2. It tracks the solar radiation in both two directions, east-west (E-W) and north-south (NS).
3. It has the advantages over single axis since it can track the sun in both horizontal and
vertical directions.
7
CHAPTER THREE
3.0 METHODOLOGY
This chapter explain method and procedure used in order to archive the objectives of project. The
following are methods and procedures taken to archive the project objectives:

Literature review

Data collection

Data analysis

Circuit designing

Simulation

Circuit implementation and testing

Project report writing
3.1 Literature review
This is one of source that makes me to reach at my project to be successfully by making a review
mostly based in the internet source and by studying the existing system (solar tracking systems)
compared with the proposed system.
3.2 Data collection
Data was collected through literature review such as reading books and searching
information from the internet. Also, by consulting expert and site visiting. During site
visiting the data was collected through observation
.3.3 Data analysis
In this part, the data collected were analyzed and processed.
3.4 Designing
The circuit design will base on information collected and analyzed in order to meet the
objectives of the project.
3.5 Circuit implementation and testing
Circuit will be implemented in the board and tested to see whether the output is the same one
obtained in simulation. Also, the result I hope it will be function
3.6 Project report writing
The report will base on the literature review, data collected and designing done.
8
3.7Simulation
After the designing of the circuit in the software the simulation was done to show if the design
gives the expected results and meets the objectives in order to get output.
Table 1 Project timeline
S/
ACTIVI
N
TY
1
WEEKS
1
2
3
4
5
6
7
8
Selectio
n of
project
title
2
Defendi
ng of the
project
title
3
Collecti
on the
data
4
Project
report
writing
5
Submiss
ion of
the
report.
9
9
1
1
1
1
1
0
1
2
3
4
15
16
Table 2 Cost estimation of the project.
SN
ITEM
UNIT
OUANTITYTY RATE
AMOUNT
1
Arduino
PCS
1
35,000/=
35,000/=
2
Servo
PCS
2
@15,000/=
30,000/=
motor
3
Solar panel
PCS
6 watts
25,000/=
25,000/
4
LDR
PCS
4
@2,500
10,000/=
5
Water
PCS
1
10,000/=
10,000/=
proof box
6
Solder wire
2m
1
@2,500/=
50,00/=
7
Jumper
5m*1.5mm
1
@1,000/=
50,00/=
wires
TOTAL
120,000/=
10
CHAPTER FOUR
4.0 DATA COLLECTION AND ANALYSIS
This describes the methods and procedures required for the development of this project. This
procedure includes the certain process per attaining objectives in accomplishment this project.
Data collections are method which use to collect data. Data are collected in order to get
information about the current system, proposed system and see if the information collected can
bring success to the development of the new system and solve the major problem of the current
system. Data collection involves many methods such as are Observation, Interview,
Questionnaire and focus group discussion but in this project it prefers using Observation and
Questionnaire.
4.1 Data Collection Methods
The project was done through different methods which were used in collection of relevant
information helpful to this project both primary and secondary data were collected, and the
methods used to collect the data are as follows.
4.1.1 Primary Data Collection
Primary data are those which are collected a fresh and for the first time and thus happen to be
original in character.
There are several methods of collecting primary data, particularly in surveys and descriptive
researches. In descriptive research, we obtain primary data either through observation or through
direct communication with respondents in one form or another or through questionnaires
4.1.2 Secondary data collection.
Secondary data are those which have been collected by someone else and which have already
been passed through the statistical process.
These are already available i.e. they refer to the data which have already been collected and
analyzed by someone else, secondary data may either be published or unpublished data.
The secondary data were collected through reviewing various books, internet searching and
through observations.
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4.1.2.1 Solar panel
Solar panels works by absorbing sunlight with photo voltaic cells, generating direct current (DC
energy and then converting it to suitable alternating current (AC energy with help of inverter
technology. AC energy then flows through the homes electrical angel and is distributed
accordingly.
Photovoltaic modules use light energy photons from the sun to generate electricity through the
photovoltaic effect.
For the solar panels to get their best performance, a steep angle of 60 is best. During the spring the
best angle is 45, and during the summer when the sun is high in the sky, it’s best to have a low tilt
at 20.
4.1.2.2 Arduino
Arduino is an open source electronics platform based on easy to use hardware and software’s. Arduino
boards are able to read inputs from a sensor and turn it into an output, for example activating a motor,
turning on a LED, or even publishing something online
4.1.2.3 Servo motors
A servo motor is a rotary actuator or a motor that allows for a precise control in terms of the angular
position, acceleration and velocity. Basically it has certain capabilities that a regular motor does
not have. Consequently it makes use of regular motor and airs it with a sensor for position
feedback.
A DC servo motor consists of a small DC motor, feedback potentiometer, gearbox, motor drive
electronic circuit and electronic feedback control loop. It is more or less similar to the normal DC
motor. The stator of the motor consists of a cylindrical frame and the magnet is attached to the
inside of the frame. [5] A brush is built with an armature coil that supplies the current to the
commutator. At the back of the shaft, a detector is built into the rotor in order to detect the rotation
speed. With this construction, it is simple to design a controller using simple circuitry because the
torque is proportional to the amount of current flow through the armature.
4.1.2.4 Light dependent resistor (LDR)
12
It is a photo-resistor is a device whose resistivity is a function of the incident electromagnetic
radiation. Hence, they are light sensitive devices. They are also called as photo conductors, photo
conductive cells or simply photocells.
They are made up of semiconductor materials having high resistance. • LDR works on the
principle of photo conductivity. [6]
Photo conductivity is an optical phenomenon in which the material’s conductivity is increased
when light is absorbed by the material. The most common type of LDR has a resistance that falls
with an increase in the light intensity falling upon the device (as shown in the image above).
The resistance of an LDR may typically have the following resistances:

Daylight = 5000Ω

Dark = 20000000Ω
4.2 DATA ANALYSIS
This chapter will provide the analysis of the data collected in the previous chapter as well as the
design, to come up with the complete circuit of the system.
4.2.1 The analysis and hence the design will rely on the following parameters components and
materials:
4.2.2 Solar cells
 Solar cells used in this design have the following types and specifications.
 Model: MY50M-12
 Type: Polycrystalline silicon solar cell
 Max Power: 3.8 Watt
 Voltage at Pmax: 6Volt
 Current at Pmax: 0.63A
 Temperature Range: -45C - +80C
13
 Dimension: 670mm x 530mm x 30mm
Cell Conversion Efficiency: 16%
Number of Cells: 36
Solar cell types are widely used to meet electricity in residential areas. This type is small and has
a low price. This solar panel is modified by adding a light sensor around it. So the dimensions of
this solar cell to be 770mm x 630mm x 330mm.
In the modified solar panel there are sensors around it that are placed in 4 positions marked with
yellow areas and numbers in sequence. So we can call the sensor parts are top-center, top-right,
top-left, bottom-left, bottom-right. [7] This solar cell has 17 x 9 cell resolution. Solar panel
placed standing on pole with a distance of 500mm above ground. This solar panel will be more
optimal if placed on the roof of a building or a house that has a flat pedestal field
4.2.3 Servo motor
 Motor Torque
Weight of Solar Panel = 0.5kg
Therefore;
Torque required to rotate the panel = Weight of panel * perpendicular distance between motor
shaft and the panel
Torque required to rotate the panel = 0.5kg * 5 cm
Torque required to rotate the panel = 2.5 kg-cm
 System consumption
o Motor Power = P = 5Watt
Considering tracking of sun for 12 hours from East to West, total 180˚ (i.e. -90˚ to +90˚)
Therefore;
Angle of rotation per Hour for motor1 = Total angle /Time
Angle of rotation per Hour for motor 1 = 180˚/12
14
Angle of rotation per Hour for motor 1 = 15˚/hour
o Motor speed is 3.5 rpm
So, for one revolution motor takes 60 seconds /3.5 rpm =17 seconds
So, to rotate half revolution required time is 17/2 = 8.5 sec. = 0.0025 hr.
Therefore;
Energy consumption by motor1=Motor Power*Time
Energy consumption by motor1= 10 * 0.0025
Energy consumption by motor1= 0.025 Whr
Energy consumption by motor1= 6.94 mWh
On consideration of seasonal tracking motor will rotate 47˚ * 2 = 94˚/year
So,
Angle of rotation per Hour for motor 2 = Total angle /Time
Angle of rotation per Hour for motor 2 = 94° 24hr∗365days
Angle of rotation per Hour for motor 2 = 0.01˚/hr.
As 0.01˚ is so small we can neglect it.
Therefore;
Total Energy consumption = Load Energy Consumption + System Consumption
Total Energy consumption = 10 + 0.00875
Total Energy consumption = 10.00875 Whr
4.2.4 DC supply/Battery
Brand: Exide
Rated Capacity: 7 Ah
Battery Voltage: 12 V
15
Items in Pack: 2 (Parallel Connected)
4.2.5 Microcontroller (Arduino)
Microcontroller: Atmega328P
Operating Voltage: 5V
Input Voltage (limits): 6-20V
Digital I/O Pins: 14
Analog Input Pins: 6
Clock Speed: 16 MHz
16
17
REFERENCE
[1] M. Lokhande, Automatic Solar Tracking System, International Journal of Core Engineering
& Management (IJCEM) Volume 1, Issue 7, ISSN: 2348 9510, October 2014.
[2] S. Rana, A Study On Automatic Dual Axis Solar Tracker System Using 555 Timer,
International Journal of Technical Research and Applications e-ISSN: 2320-8163,
www.ijtra.com Volume 1, Issue 4 (septoct 2013), PP. 77-85, 2013
[3] T. Hughes, “Measurement and Control Basic”, 3rd edition, ISA Press, 2002.
[4] K. Ogatha, “Modern Control System”, Fourth Edition, Pearson education International,
Tehran, 2002. [5] X. Jin, G. Xu, R. Zhou, X. Luo, Y. Quan, A Sun Tracking System Design For
a Large Dish Solar Concentrator, International Journal of Clean Coal and Energy, 2013, 2, 1620, May 2013.
[6] R. Banerjee, Solar Tacking System, International Journal of Scientific and Research
Publications, Volume 5, Issue 3, ISSN 2250-3153, March 2015
[7] R. Swami, Solar Cell, International Journal of Scientific and Research Publications, Volume
2, Issue 7, ISSN 2250-3153, July 2012
[8] C. De Silva, “Sensors and Actuators”, Second Edition, CRC Press Taylor and Francis Group,
2016
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