The solar tracker is used to orient various payloads toward the sun in order to trap the energy to the maximum extent. Payloads can be photovoltaic cells, reflectors, lenses or other optical devices. This tracker circuit finds the sun at dawn, follows the sun during the day, and resets for the next day. Here the payload is a Solar Photo Voltaic Panel. Sunlight has two components, the "direct beam" that carries about 90% of the solar energy, and the "diffuse sunlight" that carries the remainder .The diffuse portion is the blue sky on a clear day. As the majority of the energy is in the direct beam, maximizing collection requires the sunlight to fall straight onto the panels as long as possible. This is where the tracker comes.

1. MAXIMUM SOLAR ABSORPTION
USING DUAL AXIS SOLAR
PANEL

2. Introduction
 Solar panels are devices that convert light into electricity. They are called solar after the
sun because the sun is the most powerful source of the light available for use. They are
sometimes called photovoltaic which means "light-electricity".
 A Solar Tracker is a device onto which solar panels are fitted which tracks the motion of
the sun across the sky ensuring that the maximum amount of sunlight strikes the panels
throughout the day.
 The Solar Tracker will attempt to navigate to the best angle of exposure of light from the
sun.

3. Synopsis
• OBJECTIVE:
• The main aim of our project is to track the maximum solar energy without
radiation loss for the efficient use of solar energy, and logging data
(voltage, current).
• The problem with the existing system is stationery solar panels cannot track
maximum radiations hence most of energy is wasted.
• What we expect through logging the data is that before a user buys any solar
panel and is expecting it to work at the given rated voltage or current, he or she
can check the validity of that rating on the apparatus used for solar tracking by
our project.
• In order to overcome this, our project aims at implementing rotatory solar panel
using microcontrollers which will rotate by sensing the intensity of the radiation
and logs the data(voltage and current) for testing the capacity of the solar
panel.

4. Literature Survey
 Types of Solar Trackers:
Single Axis Tracker Dual Axis Tracker

5. STRUCTURAL DIAGRAM

6. HARDWARE DESCRIPTION
Defined as a bank of Solar cellsSolar Panel
•60 watts solar panel
•20 volts x 3 amperes
A photo-resistor or light-dependent resistor is a light-controlled variable resistor.Light Dependent Resistors
•The resistance of a photo-resistor decreases with increasing incident light intensity;
•It exhibits photoconductivity.
It is a brushless DC electric motor that divides a full rotation into a number of equal steps.Stepper Motor
•With a drive voltage of 12 to 24 volts.
•Current setting of 2.5 amps
Batteries are device which are used for storing chemical energy in form of electrical energy.Battery
•Using a nominal battery of 40 amp hour with maximum charging current of 12 amps.
A charge controller has an essential purpose to keep your batteries properly fed and safe for the long term.Charge Controller
•Battery voltage of 12 volts
•Easy installation, LED indicator
Device that detects electric current (AC or DC) in a wire, and generates a signal proportional to it.Current Sensor
•Using ACS 712 current sensor provided in a small, surface mount package, 5.0 V single supply operation
A gearbox is a collection of mechanical components that deliver maximum strength by managing a series of
gear ratios that in turn operate a transmission.Gear Box
•We are using a gear box of gear ratio 1:14.33, it means that for every one revolution of the pinion, gear has made 0.433 revolutions.

7. PROGRAMMER’S CONSIDERATIONS
√ Using ARDUINO MEGA 2560
microcontroller.
 Having 54 digital input/output
pins.
 16 analog inputs
 256 KB flash memory
 Each pin can provide max of 40mA
√ With ARDUINO as the
programming language

8. Arduino Breakout Board
 A project with any audio, video, graphics, data
logging, etc in it, you'll find that having a
removable storage option is essential.
 They are strictly 3.3V devices and the power
draw when writing to the card can be fairly high,
up to 100mA.
 Arduino mega uses digital pins as 50 (MISO), 51
(MOSI), 52 (SCK), and for the CS line, the most
common pin is 53 (SS).

9. Design for Voltage Divider
 Voltage divider circuit is used as a voltage sensor. The
maximum voltage extracted from the solar panel is
20V.
 But the arduino microcontroller board is devised for
working on atmost 5 V therefore using a voltage
divider circuit to protect the board circuitry.
 Therefore it is designed as,
Vo= (Vin x R2)/(R1+R2)
Given Vinmax = 20 Volts
Vomax= 5 Volts
Assume R2=1.5KΩ
Therefore R1= 4.55KΩ

10. Testing Procedures
•Solar panel testing is done by checking its output voltage and current. by connecting the solar panel output to the
charge controller and the values for voltage and current at different times of the day for the rotating and static solar
panel is tabulated
Solar Panel:
•The battery is tested by checking it’s charging and discharging time. Connecting the battery to a high current
consuming load like a charger may reduce its discharging time.
Battery Testing:
•Stepper motor is tested by energizing the motor coils and by giving clock pulses for a particular period of time to the
motor driver.
Motor Testing:
•The sensors were tested for proper measurement of voltage and current through ammeters and voltmeters around the
load resistors.
Sensor Testing:
•The LDRs are mounted on the panel based on the sensor ouput panel rotated either in CW or CCW direction throughout
the day to duly test the limitations of the assembly.
Solar Tracker Assembly Testing:

11. WORKING MODEL
 Stepper motor is used for EAST to
WEST rotation of the solar panel on
the daily basis.
 For the NORTH to SOUTH axis rotation
manual handling is advised.

12. Results

13. Results (contd.)

14. Future Scope
 Fabrication of Microcontroller using ASIC concepts: The number of wires can be greatly
reduced by directly if a customized PCB is made upon which all the resistors can be directly
soldered. This also eliminates the use of a Breadboard which was used to make all the
external connections.
 Mounting of the Panels: In our design, the panels are mounted on a horizontal shaft supported
strongly at both ends. We can mount the panels directly onto a motor placed at the center of
the Panel-Base in order to provide East-West movement. This reduces the weight and effective
cost of the project.

15. APPLICATIONS
Main Applications can be enumerated as:
 Alternative power source
 As the solar apparatus charges the battery during its ON
time thus that can be used as a secondary power source.

16.  Used as a measuring instrument for other solar panels
 For this application it is needed to store data in memory,
using arduino we have done it to micro-sd card which anyone
can check on their smartphones.
 Using the same apparatus for measuring the extent of
efficiency for a solar panel will be much cost effective for the
newbies in this area of power.
TIME VOLTAGE(volts) CURRENT(amps)
7.15 am 12.71 0.42
7.30 am 13.03 0.72
7.45 am 13.15 1.09
8.00 am 13.28 1.43
8.15 am 13.59 1.80
8.30 am 13.63 1.80
9.00 am 14.65 1.83
9.20 am 15.5 2.03
9.40 am 17.6 2.1
10.00 am 18 2.15
10.15 am 18.5 2.19
10.45 am 18.7 2.3
11.15 am 18.9 2.49
11.50 am 19.0 2.51
12.30 pm 19.0 2.53

17. CONCLUSION
MERITS
 Clean and green source of power.
 Solar panels are reasonably easy, safe and
convenient to install.
 One time investment which provides higher
efficiency and reliability.
 Solar Tracking systems continually orient
PV panels towards the sun and can help
maximize the investment on PV system.
DEMERITS
 Initial investment is high.
 Moving parts such as gears needs periodic
maintenance.
 Maintenance and repairing of mechanical
and electronic parts of the tracking system
requires extra man-power and of extra
investment.
 Has to be built extreme environmental
conditions such as storms, heavy rainfall
etc.