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MaximumSolarAbsorptionusingDual AxisSolarPanel
Dept. of ECE,PESIT-BSC 1
CONTENTS
PAGE NO:
CHAPTER 1: PREAMBLE
1.1: INTRODU...
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CHAPTER 8: APPLICATIONS
8.1: ALTERNATE ENERGY SOUR...
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CHAPTER 1
PREAMBLE
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CHAPTER 1
PREAMBLE
1.1 INTRODUCTION
One of the mos...
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In order to overcome this, our project aims at imp...
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Evolution of SolarTracker:
Since the sun moves acr...
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1.3 LIST OF FIGURES:
1. Sun’s apparent position 6
...
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1.3 BASIC BLOCK DIAGRAM
Fig.2
The solar panel is d...
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1.3 BLOCK DIAGRAM FOR READY PROJECT
Fig.3
Fig.4
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CHAPTER 2
LITERATURE SURVEY
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LITERATURE REVIEW
Sun-synchronous navigation is r...
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energy of the panels by keeping the panel’s face ...
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CHAPTER 3
SENSORS
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SENSORS
3.1 PHOTOSENSORS
Light Dependent Resistor...
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3.2 CURRENT SENSORS
Fig.6
A current sensor is a d...
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The ACS712 Low Current Sensor Breakout outputs an...
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MATHEMATICS INVOLVED IN ADC CONVERSION:
ACS712: 5...
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CHAPTER 4
MODULES
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4.1 SOLAR TRACKER ASSEMBLY
DRIVE TYPES:
Active tr...
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4.2 MOTOR CONTROL
Motor is use to drive the Solar...
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Bipolar vs. Unipolar stepper motors
The two commo...
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Many microprocessor systems use four output lines...
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can all be derived from four values: the motor’s ...
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Here is a basic explanation of how the gearbox wo...
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amps, the charge voltage can be kept at an optima...
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Although there are different types of battery but...
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immediately connected to a battery charger. If a ...
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CHAPTER 5
MECHANICS
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5.1 PLUMMER BLOCK
A pillow block, also known as a...
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Fig.15
5.2 BALL BEARING
A ball bearing is a type ...
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Fig.16
5.3 SYSTEM SCHEMATIC
Fig.17
Mounting Syste...
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 The plumber blocks are used to provide support ...
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CHAPTER 6
SOFTWARE
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6.1 ARDUINO
The Arduino integrated development en...
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ARDUINO MEGA2560:
The Arduino Mega 2560 is a micr...
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Fig.21
6.2 ARDUINO BREAKOUT BOARD
Fig.22
If you h...
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There are a few things to watch for when interact...
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FLOWCHART FOR STEPPERMOTOR ROTATION:
Start
Initia...
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?
sd.begin(53)
FLOWCHART FOR SD CARD DATA LOGGING...
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CHAPTER 7
TESTING
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SOLAR PANEL
 A solar panel is an assembly of pho...
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GEAR BOX
 The gear box used in the design to hol...
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CHAPTER 8
APPLICATIONS
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8.1 ALTERNATE ENERGYSOURCE
The Earth receives an ...
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For constant solar panel
TIME VOLTAGE(volts) CURR...
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For rotating solar panel east -xº +xº west
Angle ...
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Fig.23
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Fig.24
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8.2 PANEL MEASURING APPARATUS
We have also expand...
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CHAPTER 9
CONCLUSION
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9.1 CONCLUSION:
With Global Warming constantly af...
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2. Environmentally friendly
Solar Energy is clean...
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BIBLIOGRAPHY:
[1] Rizk J. and Chaiko Y. “Solar Tr...
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APPENDIX 1
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A1.1 MILESTONES:
Fig.26
JANUARY 2015:
 For the s...
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MARCH 2015:
 Unlike the first model design the s...
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A1.2 ACTIVITIES & GANNT CHART:
Fig.27
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Maximum solar absorption using dual axis solar panel report

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.

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Maximum solar absorption using dual axis solar panel report

  1. 1. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 1 CONTENTS PAGE NO: CHAPTER 1: PREAMBLE 1.1: INTRODUCTION 4 1.2: LIST OF FIGURES 7 1.3: BASIC BLOCK DIAGRAM 8 1.4: BLOCK DIAGRAM FOR 9 THE READY PROJECT CHAPTER 2: LITERATURE SURVEY 11 CHAPTER 3: SENSORS 3.1: PHOTOSENSORS 14 3.2: CURRENT SENSORS 15 CHAPTER 4: MODULES 4.1: SOLAR TRACKER ASSEMBLY 19 4.2: MOTOR CONTROL 20 4.3: GEAR CONTROL 22 4.4: CHARGE CONTROLLER 24 4.5: BATTERY 25 CHAPTER 5: MECHANICS 5.1: PLUMMER BLOCK 29 5.2: BALL BEARING 30 5.3: SCHEMATIC ASSEMBLY 31 CHAPTER 6: SOFTWARE 6.1: ARDUINO (SOFTWARE) 34 6.2: ARDUINO BREAKOUT BOARD 36 6.3: FLOW CHARTS 38 CHAPTER 7: TESTING 41
  2. 2. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 2 CHAPTER 8: APPLICATIONS 8.1: ALTERNATE ENERGY SOURCE 44 8.2: PANEL MEASURING APPARATUS 49 CHAPTER 9: CONCLUSION 9.1: CONCLUSION 51 9.2: FUTURE ENHANCEMENTS 52 BIBLIOGRAPHY 53 APPENDIX 1 A1.1 MILESTONES AND TARGETS 55 A1.2 ACTIVITIES AND GANNT CHART 57
  3. 3. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 3 CHAPTER 1 PREAMBLE
  4. 4. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 4 CHAPTER 1 PREAMBLE 1.1 INTRODUCTION One of the most promising renewable energy sources characterized by a huge potential of conversion into electrical power is the solar energy. The conversion of solar radiation into electrical energy by Photo-Voltaic (PV) effect is a very promising technology, being clean, silent and reliable, with very small maintenance costs and small ecological impact. The continuous evolution of the technology determined a sustained increase of the conversion efficiency of PV panels, but nonetheless the most part of the commercial panels have efficiencies no more than 20%. A constant research preoccupation of the technical community involved in the solar energy harnessing technology refers to various solutions to increase the PV panel’s conversion efficiency. The continuous modification of the sun-earth relative position determines a continuously changing of incident radiation on a fixed PV panel. The point of maximum received energy is reached when the direction of solar radiation is perpendicular on the panel surface. Thus an increase of the output energy of a given PV panel can be obtained by mounting the panel on a solar tracking device that follows the sun trajectory. PVs offer added advantages over other renewable energy sources in that they give off no noise and require practically no maintenance. A tracking system must be able to follow the sun with a certain degree of accuracy, return the collector to its original position at the end of the day and also track during periods of cloud over. The major components of this system are as follows.  Light dependent resistor  Microcontroller  Output mechanical transducer (stepper motor) The main aim of our project is to track the maximum solar energy without radiation loss for the efficient use of solar energy. The problem with the existing system is stationary solar panels cannot track maximum radiations hence most of energy is wasted.
  5. 5. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 5 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 for the efficient utilization of tracked solar energy and avoid unnecessary usage of power when not in use. BACKGROUND: By using solar arrays, a series of solar cells electrically connected, a DC voltage is generated which can be physically used on a load. Solar arrays or panels are being used increasingly as efficiencies reach higher levels, and are especially popular in remote areas where placement of electricity lines is not economically viable. This alternative power source is continuously achieving greater popularity especially since the realization of fossil fuels shortcomings. Renewable energy in the form of electricity has been in use to some degree as long as 75 or 100 years ago. Sources such as Solar, Wind, Hydro and Geothermal have all been utilized with varying levels of success. The most widely used are hydro and wind power, with solar power being moderately used worldwide. 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. Technology of Solar Panel: 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". Solar cells or PV cells rely on the photovoltaic effect to absorb the energy of the sun and cause current to flow between two oppositely charge layers. A solar panel is a collection of solar cells. Although each solar cell provides a relatively small amount of power, many solar cells spread over a large area can provide enough power to be useful. To get the most power, solar panels have to be pointed directly at the Sun. The development of solar cell technology begins with 1839 research of French physicist Antoine-Cesar Becquerel. He observed the photovoltaic effect while experimenting with a solid electrode in an electrolyte solution. After that he saw a voltage developed when light fell upon the electrode.
  6. 6. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 6 Evolution of SolarTracker: Since the sun moves across the sky throughout the day, in order to receive the best angle of exposure to sunlight for collection energy. A tracking mechanism is often incorporated into the solar arrays to keep the array pointed towards the sun. 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. When compare to the price of the PV solar panels, the cost of a solar tracker is relatively low. Most photovoltaic solar panels are fitted in a fixed location- for example on the sloping roof of a house, or on framework fixed to the ground. Since the sun moves across the sky though the day, this is far from an ideal solution. Solar panels are usually set up to be in full direct sunshine at the middle of the day facing South in the Northern Hemisphere, or North in the Southern Hemisphere. Therefore morning and evening sunlight hits the panels at an acute angle reducing the total amount of electricity which can be generated each day. Fig1.Sun’sapparentmotion During the day the sun appears to move across the sky from left to right and up and down above the horizon from sunrise to noon to sunset. Figure shows the schematic above of the Sun's apparent motion as seen from the Northern Hemisphere.
  7. 7. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 7 1.3 LIST OF FIGURES: 1. Sun’s apparent position 6 2. Basic block diagram 8 3. Final block diagram of prepared project 9 4. Working flowchart for block diagram 9 5. Light dependent resistor 14 6. Current sensor ACS712 15 7. Current sensor pin out 15 8. Voltage divider circuit 17 9. Types of trackers 19 10. Stepper motor 20 11. Unipolar and bipolar motors 21 12. Gear box 23 13. Gear box cross section 23 14. Charge controller 25 15. Plummer block 30 16. Ball bearing 31 17. Schematic assembly of tracker 31 18. Snapshot of the assembly 32 19. Arduino Uno snapshot 34 20. ARDUINO pin out 34 21. ARDUINO MEGA 2560 board 36 22. ARDUINO breakout board 36 23. Constant solar panel current and voltage vs time graph 47 24. Rotating solar panel current and voltage vs time graph 48 25. Snapshot of voltage & current readings 49 26. Milestones 55 27. Gantt chart 57
  8. 8. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 8 1.3 BASIC BLOCK DIAGRAM Fig.2 The solar panel is designed in such a way that maximum efficiency is obtained. The solar energy from sun is converted into electrical energy by the use of photovoltaic cells. This power from solar panels cannot be used directly to charge the battery directly so we use a charge controller. To facilitate this charge controller is developed. We use a dc to dc converter which is given to load regulator which monitors the load. A pressure sensor is used to monitor the incoming or outgoing person so, the lights are on or off. TOOLS: Hardware: Solar panel, Geared Motor, Load, Sensors, Microcontroller unit.
  9. 9. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 9 1.3 BLOCK DIAGRAM FOR READY PROJECT Fig.3 Fig.4
  10. 10. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 10 CHAPTER 2 LITERATURE SURVEY
  11. 11. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 11 LITERATURE REVIEW Sun-synchronous navigation is related to moving the solar powered rover (robot) in such a way that its solar panel always points toward the sun and which results into maximum battery charging and hence the rover can work for long hours. The unique feature of this solar tracking system is that instead of taking the earth as its reference, it takes the sun as a guiding source. Its active sensors constantly monitor the sunlight and rotate the panel towards the direction where the intensity of sunlight is maximum. The light dependent resistor’s do the job of sensing the change in the position of the Sun. The control circuit does the job of fetching the input from the sensor and gives command to the motor to run in order to tackle the change in the position of the sun. By using this system the additional energy generated is around 25% to 30% with very less consumption by the system itself. The project describes the use of a microcontroller based design methodology of an automatic solar tracker. Light dependent resistors are used as the sensors of the solar tracker. The tracking system maximizes solar cell output by positioning a solar panel at the point of maximum light intensity. This paper describe the use of DC motors, special motors like stepper motors, servo motors, real time actuators, to operate moving parts of the solar tracker. The system was designed as the normal line of solar cell always move parallel to the rays of the sun. The Aim of one of the referred project publications is to develop and implement a prototype of two-axis solar tracking system based on a microcontroller. The parabolic reflector or parabolic dish is constructed around two feed diameter to capture the sun’s energy. The focus of the parabolic reflector is pointed to a small area to get extremely high temperature. The temperature at the focus of the parabolic reflector is measured with temperature probes. This auto-tracking system is controlled with two 12V, 6W DC gear box motors. The five light sensors (LDR) are used to track the sun and to start the operation (Day/Night operation). The paper adopts the PWM DC motor controller. It is capable of archiving the timeliness, reliability and stability of motor speed control, which is difficult to implement in traditional analog controller. The project concentrates on the design and control of dual axis orientation system for the photovoltaic solar panels. The orientation system calculations are based on astronomical data and the system is assumed to be valid for any region with small modifications. The system is designed to control the Altitude angle in the vertical plane as well as the Azimuth angle in the horizontal plane of the photovoltaic panel workspace. And this system is expected to save more than 40% of the total
  12. 12. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 12 energy of the panels by keeping the panel’s face perpendicular to the sun. In the previous solutions, each tracking direction is controlled by using a Sun sensor made by a pair of phototransistors. Sensor control is that sunray is detected by photoelectric detector and then the changed signal is transmitted to control step motor to adjust the attitude of the solar. The paper discusses the technology options, their current status and opportunities and challenges in developing solar thermal power plants in the context of India. The National Solar Mission is a major initiative of the Government of India and State Governments to promote ecologically sustainable growth while addressing India’s energy security challenge. It will also constitute a major contribution by India to the global effort to meet the challenges of climate change.
  13. 13. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 13 CHAPTER 3 SENSORS
  14. 14. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 14 SENSORS 3.1 PHOTOSENSORS Light Dependent Resistor Light Dependent Resistor is made of a high-resistance semiconductor. It can also be referred to as a photoconductor. If light falling on the device is of the high enough frequency, photons absorbed by the semiconductor give bound electrons enough energy to jump into the conduction band. The resulting free electron conducts electricity, thereby lowering resistance. Hence, Light Dependent Resistors is very useful in light sensor circuits. LDR is very high-resistance, sometimes as high as 10MΩ, when they are illuminated with light resistance drops dramatically. A photo resistor is a passive component and does not have a PN-junction. The photo resistivity of any photo resistor may vary widely depending on ambient temperature, making them unsuitable for applications requiring precise measurement of or sensitivity to light. We are using two LDR’s at opposite ends of the solar panel to increase the light detection efficiency of the solar tracker, with a 10K POT for control. A Light Dependent Resistor is a resistor that changes in value according to the light falling on it. A commonly used device, the ORP-12, has a high resistance in the dark, and a low resistance in the light. Connecting the LDR to the microcontroller is very straight forward, but some software ‘calibrating’ is required. Fig.5
  15. 15. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 15 3.2 CURRENT SENSORS Fig.6 A current sensor is a device that detects electric current (AC or DC) in a wire, and generates a signal proportional to it. The generated signal could be analog voltage or current or even digital output. It can be then utilized to display the measured current in an ammeter or can be stored for further analysis in a data acquisition system or can be utilized for control purpose. ACS712 provides economical and precise solutions for AC or DC current sensing in industrial, commercial, and communications systems. Fig.7
  16. 16. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 16 The ACS712 Low Current Sensor Breakout outputs an analog voltage that varies linearly with sensed current. To calibrate, first set the output offset to the desired level (with zero current on the sense lines, read output with a DVM). Then with a known current input (a 100mA limited supply works well for this), set the output deflection with the gain pot. Sensitivity is then calculated as (Vref - Vdeflect)/ (current input). Features and Benefits ▪ Low-noise analog signal path ▪ 5 μs output rise time in response to step input current ▪ Total output error 1.5% at TA = 25°C ▪ 1.2 mΩ internal conductor resistance ▪ 2.1 kVRMS minimum isolation voltage from pins 1-4 to pins 5-8 ▪ 5.0 V, single supply operation ▪ 66 to 185 mV/A output sensitivity ▪ Output voltage proportional to AC or DC currents ▪ Factory-trimmed for accuracy ▪ Extremely stable output offset voltage ▪ Nearly zero magnetic hysteresis ▪ Ratiometric output from supply voltage
  17. 17. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 17 MATHEMATICS INVOLVED IN ADC CONVERSION: ACS712: 5amps current sensor has sensitivity of 0.185 V/Amp For Vcc = 5V and ADC Vref=Vcc Relationship between input voltage and ADC count is Count = (1024/Vcc) x Vin But Vin =(Vcc/2)+0.185(I) Count =(1024/Vcc)x {(Vcc/2)+0.185(I)} I =0.0264 x (count -512) Voltage Sensing Circuit Fig.8 Voltage divider circuit is used as a voltage sensor. The maximum voltage extracted from the solar panel is 20 V. But the arduino microcontroller board is devised for working on atmost 5 V therefore we are using a voltage divider circuit as shown above with values designed as: Vo= (Vin x R2)/(R1+R2) Given Vinmax = 20 Volts Vomax= 5 Volts Assume R2=1.5KΩ Therefore R1= 4.55KΩ
  18. 18. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 18 CHAPTER 4 MODULES
  19. 19. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 19 4.1 SOLAR TRACKER ASSEMBLY DRIVE TYPES: Active tracker Active trackers use motors and gear trains to direct the tracker as commanded by a controller responding to the solar direction. As each mirror in a large field will have an individual orientation these are controlled programmatically through a central computer system, which also allows the system to be shut down when necessary. Passive tracker Passive trackers use a low boiling point compressed gas fluid that is driven to one side or the other (by solar heat creating gas pressure) to cause the tracker to move in response to an imbalance. As this is a non-precision orientation it is unsuitable for certain types of concentrating photovoltaic collectors but works fine for common PV panel types. These will have viscous dampers to prevent excessive motion in response to wind gusts. Shader/reflectors are used to reflect early morning sunlight to "wake up" the panel and tilt it toward the sun, which can take nearly an hour. Fig.9 Single Axis Trackers: •A single axis trackercanpivot inonlyone plane – horizontalor vertical. The horizontaltype is usedin tropical regions where the sun gets veryhighat noon, but the days are short. The vertical type is used inhigh latitudes (suchas inUK) where the sundoesnot get very high, but summerdays canbe verylong. •Although the construction is less complicatedit is also less effective inharnessingthe total solar energy. Dual Axis Trackers: •Dual axis solartracker has two degrees of freedom that act as axes of rotation.These axes are typically normal to one another. •It can rotate simultaneously in horizontal and vertical directions and areableto point at the sun at all times.Dual axis trackers track thesun both East to West and North to South for added power output (approx.40% gain) and convenience.
  20. 20. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 20 4.2 MOTOR CONTROL Motor is use to drive the Solar Tracker to the best angle of exposure of light. For this section, we are using stepper motor. Stepper Motor Features  Linear speed control of stepper motor  Control of acceleration, deceleration, max speed and number of steps to move  Driven by one timer interrupt  Full - or half-stepping driving mode  Supports all AVR devices with 16bit timer Introduction The stepper motor is an electromagnetic device that converts digital pulses into mechanical shaft rotation. Many advantages are achieved using this kind of motors, such as higher simplicity, since no brushes or contacts are present, low cost, high reliability, high torque at low speeds, and high accuracy of motion. Fig.10
  21. 21. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 21 Bipolar vs. Unipolar stepper motors The two common types of stepper motors are the bipolar motor and the Unipolar motor. The bipolar and unipolar motors are similar, except that the Unipolar has a centre tap on each winding. Fig.11 Unipolar stepper motor Stepper motors are very accurate motors that are commonly used in computer disk drives, printers and clocks. Unlike dc motors, which spin round freely when power is applied, stepper motors require that their power supply be continuously pulsed in specific patterns. For each pulse the stepper motor moves around one step often 15 degrees giving 24 steps in a full revolution. There are two main types of stepper motors - Unipolar and Bipolar. Unipolar motors usually have four coils which are switched on and off in a particular sequence. Bipolar motors have two coils in which the current flow is reversed in a similar sequence. Each of the four coils in a Unipolar stepper motor must be switched on and off in a certain order to make the motor turn.
  22. 22. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 22 Many microprocessor systems use four output lines to control the stepper motor, each output line controlling the power to one of the coils. As the stepper motor operates at 5V, the standard transistor circuit is required to switch each coil. As the coils create a back emf when switched off, a suppression diode on each coil is also required. The table below show the four different steps required to make the motor turn. Bipolar Stepper motor The bipolar stepper motor has two coils that must be controlled so that the current flows in different directions through the coils in a certain order. The changing magnetic fields that these coils create cause the rotor of the motor to move around in steps. The bipolar motor needs current to be driven in both directions through the windings, and a full bridge driver is needed as shown in Figure. The center tap on the Unipolar motor allows a simpler driving circuit shown in Figure, limiting the current flow to one direction. The main drawback with the Unipolar motor is the limited capability to energize all windings at any time, resulting in a lower torque compared to the bipolar motor. The Unipolar stepper motor can be used as a bipolar motor by disconnecting the center tap. DESCRIPTION RATING Drive Voltage 12 to 24 volts Current setting 2.5amps per phase Type Bipolar/micro- stepping Maximuminput frequency 50KHz Outermost size 42 x 42 x 30mm 4.3 GEAR CONTROL A gearbox is defined as the metal casing within which a train of gears is sealed. There are several important characteristics of motors that provide information about a motor and its capabilities. They are the motor’s output torque, its current draw, its output speed, its power, and its efficiency, each of which I will discuss in turn. These characteristics are interdependent and
  23. 23. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 23 can all be derived from four values: the motor’s stall torque, stall current, free current, and free speed. The gear ratio of a gear train, also known as its speed ratio, is the ratio of the angular velocity of the input gear to the angular velocity of the output gear. The gear ratio can be calculated directly from the numbers of teeth on the gears in the gear train. Fig.12 The gear ratio used in this application is 1:14.33 means that for every one revolution of the pinion, the gear has made 1/14.33, revolutions. In practical terms, the gear turns more slowly. Fig.13
  24. 24. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 24 Here is a basic explanation of how the gearbox works. The engine drives the input shaft. The gears transfer the torque to the output shaft. This shaft has a pinion on it which drives the ring gear around the diff assembly. These two parts determine the final drive ratio of the vehicle, and as it is before the diff they can be changed independent of any other ratio. The ring gear is around the center diff. This diff splits the torque between front and rear axle. Think of it purely as a normal diff, with two output shafts for now. One of these shafts goes to the front diff, which acts in the normal matter to split torque between the front two wheels. The other goes to the rear diff, just like a rwd car. 4.4 CHARGE CONTROLLER A solar charge controller or regulator is a small box consisting of solid state circuits pcb which is placed between a solar panel and a battery. Its function is to regulate the amount of charge coming from the panel that flows into the battery bank in order to avoid the batteries being overcharged. A charge controller limits the rate at which electric current is added to or drawn from electric batteries. It prevents overcharging and may prevent against overvoltage, which can reduce battery performance or lifespan, and may pose a safety risk. It may also prevent completely draining ("deep discharging") a battery, or perform controlled discharges, depending on the battery technology, to protect battery life. A solar charge controller is needed in virtually all solar power systems that utilize batteries. The job of the solar charge controller is to regulate the power going from the solar panels to the batteries. Overcharging batteries will at the least significantly reduce battery life and at worst damage the batteries to the point that they are unusable. Most solar power systems use 12 volt batteries, like you find in cars. (Some use other voltages and the same advantages apply to these systems as well.) Solar panels can deliver far more voltage than is required to charge the batteries. By, in essence, converting the excess voltage into
  25. 25. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 25 amps, the charge voltage can be kept at an optimal level while the time required to fully charge the batteries is reduced. This allows the solar power system to operate optimally at all times. Fig.14 4.5 BATTERY Batteries are device which are used for storing chemical energy in form of electrical energy. It consists of one or more electrochemical cells. Although there are different types of battery but for PV systems lead acid batteries are preferred. When buying a battery, there are several factors that should be taken into account to determine the total cost of ownership over the life of the battery. • The Most Important Consideration – Cycle Life: While the factors above are important, the most critical consideration is cycle life, which measures the number of discharge/charge cycles the battery can provide before capacity drops to a specified percentage of its rated capacity. • Capacity: A battery’s capacity is very important since it is the measurement of the amount of energy stored in the battery. • Voltage: The battery bank voltage must be considered to ensure it matches the system requirements. By the voltage of the loads in a DC system.
  26. 26. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 26 Although there are different types of battery but for PV systems lead acid batteries are preferred. This kind of battery needs charging when 60% of its capacity is used and is superior to all other batteries in terms of price to power ratio. Advantages of Lead Acid Batteries:  It is robust and reliable and cheap.  Has slight tolerance towards overcharging.  Has low internal impedance  Ability to deliver high current.  Comes in variety of charge and storage capacities. Disadvantages of Lead Acid Batteries:  Must be stored in charged state to avoid crystallization of cells.  Charge efficiency is 55 to 60%.  Cycle life of 300 to 500 cycles.  Cannot be charged very fast. Lead Acid Batter Discharge Cycle: A fully charged battery is connected to a load (light bulb) and the chemical reaction between sulfuric acid and the lead plates produces the electricity to light the bulb. This chemical reaction also begins to coat both positive and negative plates with a substance called lead sulfate also known as sulfation (shown as a yellow build-up on plates). This build-up of lead sulfate is normal during a discharge cycle. As the battery continues to discharge, lead sulfate coats more and more of the plates and battery voltage begins to decrease from fully charged state of 12.6- volts. The battery is now fully discharged, the plates are almost completely covered with lead sulfate (sulfation) and voltage has dropped to 10.5-volts. Lead sulfate (sulfation) now coats most of the battery plates. Lead sulfate is a soft material, which can is reconverted back into lead and sulfuric acid, provided the discharged battery is
  27. 27. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 27 immediately connected to a battery charger. If a lead acid battery is not immediately recharged, the lead sulfate will begin to form hard crystals, which cannot be reconverted by a standard fixed voltage (13.6 volts) battery converter/charger. Lead Acid Battery Recharge Cycle The discharged battery is connected to a converter/charger with its output voltage set at 13.6- volts. In order to recharge a 12-volt lead acid battery with a fully charged terminal voltage of 12.6-volts, the charger voltage must be set at a higher voltage. Most converter/chargers on the market are set at approximately 13.6-volts. During the battery recharge cycle lead sulfate (sulfation) begins to reconvert to lead and sulfuric acid. During the recharging process as electricity flows through the water portion of the electrolyte and water, (H2O) is converted into its original elements, hydrogen and oxygen. These gasses are very flammable and the reason your RV or Marine batteries must be vented outside. Gassing causes water loss and therefore lead acid batteries need to have water added periodically. Sealed lead acid batteries contain most of these gasses allowing them to recombine into the electrolyte. If the battery is overcharged pressure from these gasses will cause relief caps to open and vent, resulting in some water loss. Most sealed batteries have extra electrolyte added during the manufacturing process to compensate for some water loss. DESCRIPTION RATING Nominal Voltage 12 volts Nominal Capacity 40Amp hr Max Charging current 12 A
  28. 28. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 28 CHAPTER 5 MECHANICS
  29. 29. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 29 5.1 PLUMMER BLOCK A pillow block, also known as a plummer block or bearing housing, is a pedestal used to provide support for a rotating shaft with the help of compatible bearings & various accessories. Housing material for a pillow block is typically made of cast iron or cast steel. Pillow blocks are usually referred to the housings which have a bearing fitted into them and thus the user need not purchase the bearings separately. Pillow blocks are usually mounted in cleaner environments and generally are meant for lesser loads of general industry. These differ from "plummer blocks" which are bearing housings supplied without any bearings and are usually meant for higher load ratings and corrosive industrial environments. However the terms pillow block and plummer block are used interchangeably in certain parts of the world. The fundamental application of both types is the same which is to mount bearings safely enabling their outer ring to be stationary while allowing rotation of the inner ring. The housing is bolted to a foundation through the holes in the base. Bearing housings are either split type or unsplit type. Split type housings are usually two piece housings where the cap and base can be detached, while certain series are one single piece housings. Various seals are provided to prevent dust and other contaminants from entering the housing. Thus the housing provides a clean environment for the expensive bearings to freely rotate, hence increasing their performance and duty cycle. Bearing housings are usually made of grey cast iron. However various grades of metals can be used to manufacture the same. ISO 113 specifies internationally accepted dimensions for plummer blocks.
  30. 30. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 30 Fig.15 5.2 BALL BEARING A ball bearing is a type of rolling-element bearing that uses balls to maintain the separation between the bearing races. The purpose of a ball bearing is to reduce rotational friction and support radial and axial loads. It achieves this by using at least two races to contain the balls and transmit the loads through the balls. In most applications, one race is stationary and the other is attached to the rotating assembly (e.g., a hub or shaft). As one of the bearing races rotates it causes the balls to rotate as well. Because the balls are rolling they have a much lower coefficient of friction than if two flat surfaces were sliding against each other. Ball bearings tend to have lower load capacity for their size than other kinds of rolling-element bearings due to the smaller contact area between the balls and races. However, they can tolerate some misalignment of the inner and outer races. For a bearing to operate properly, it needs to be lubricated. In most cases the lubricant is based on elastohydrodynamic effect (by oil or grease) but working at extreme temperatures dry lubricated bearings are also available. For a bearing to have its nominal lifespan at its nominal maximum load, it must be lubricated with a lubricant (oil or grease) that has at least the minimum dynamic viscosity (usually denoted with the Greek letter ) recommended for that bearing. The recommended dynamic viscosity is inversely proportional to diameter of bearing.
  31. 31. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 31 Fig.16 5.3 SYSTEM SCHEMATIC Fig.17 Mounting System  The mounting system refers to the structure which holds the solar panels, the structure consist of movable and fixed parts based on a set of criteria.  The structure must be able to support the weight of the solar panel which is mounted on it. Fabrication  The base part of mounting system is shown above.
  32. 32. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 32  The plumber blocks are used to provide support for a rotating shaft with the help of compatible bearings.  At the one end of the metal shaft stepper motor is mounted with gear box. Gear box with stepper motor controls the east to west rotation of solar panel. The below structure is mounted on shaft for north to south rotation. The solar panel frame is mounted on the top. Fig.18
  33. 33. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 33 CHAPTER 6 SOFTWARE
  34. 34. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 34 6.1 ARDUINO The Arduino integrated development environment (IDE) is a cross-platform application written in Java, and derives from the IDE for the Processing programming language and the Wiring projects. It is designed to introduce programming to artists and other newcomers unfamiliar with software development. It includes a code editor with features such as syntax highlighting, brace matching, and automatic indentation, and is also capable of compiling and uploading programs to the board with a single click. A program or code written for Arduino is called a "sketch". These systems provide sets of digital and analog I/O pins that can be interfaced to various extension boards and other circuits. The boards feature serial communications interfaces, including USB on some models, for loading programs from personal computers. For programming the microcontrollers, the Arduino platform provides an integrated development environment (IDE) based on the Processing project, which includes support for C and C++ programming languages. Arduino programs are written in C or C++. The Arduino IDE comes with a software library called "Wiring" from the original Wiring project, which makes many common input/output operations much easier. Fig.19 Fig.20
  35. 35. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 35 ARDUINO MEGA2560: The Arduino Mega 2560 is a microcontroller board based on the ATmega2560. It has 54 digital input/output pins (of which 15 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. The power pins are as follows:  VIN. The input voltage to the Arduino board when it's using an external power source (as opposed to 5 volts from the USB connection or other regulated power source). You can supply voltage through this pin, or, if supplying voltage via the power jack, access it through this pin.  5V. This pin outputs a regulated 5V from the regulator on the board. The board can be supplied with power either from the DC power jack (7 - 12V), the USB connector (5V), or the VIN pin of the board (7-12V). Supplying voltage via the 5V or 3.3V pins bypasses the regulator, and can damage your board.  3V3. A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA.  GND. Ground pins.  IOREF. This pin on the Arduino board provides the voltage reference with which the microcontroller operates. A properly configured shield can read the IOREF pin voltage and select the appropriate power source or enable voltage translators on the outputs for working with the 5V or 3.3V. In addition, some pins have specialized functions. The Arduino Mega2560 has a resettable polyfuse that protects your computer's USB ports from shorts and overcurrent. Although most computers provide their own internal protection, the fuse provides an extra layer of protection. If more than 500 mA is applied to the USB port, the fuse will automatically break the connection until the short or overload is removed.
  36. 36. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 36 Fig.21 6.2 ARDUINO BREAKOUT BOARD Fig.22 If you have a project with any audio, video, graphics, data logging, etc in it, you'll find that having a removable storage option is essential. Most microcontrollers have extremely limited built-in storage. For example, even the Arduino Mega chip (the Atmega2560) has a mere 4Kbytes of EEPROM storage. There's more flash (256K) but you can't write to it as easily and you have to be careful if you want to store information in flash that you don't overwrite the program itself! To get that kind of storage we're going to use the same type that's in every digital camera and mp3 player: flash cards! Often called SD or microSD cards, they can pack gigabytes into a space smaller than a coin. They're also available in every electronics shop so you can easily get more and best of all, many computers have SD or microSD card readers built in so you can move data back and forth between say your Arduino GPS data logger and your computer graphing software.
  37. 37. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 37 There are a few things to watch for when interacting with SD cards: One is that they are strictly 3.3V devices and the power draw when writing to the card can be fairly high, up to 100mA (or more)! That means that you must have a fairly good 3.3V power supply for the card. Secondly you must also have 3.3V logic to interface to the pins. We've found that SD cards are fairly sensitive about the interface pins - the newest cards are edge triggered and require very 'square' transitions - things like resistor dividers and long wires will have a deleterious effect on the transition speed, so keep wires short, and avoid using resistor dividers for the 3.3V logic lines. SD cards require a lot of data transfer, they will give the best performance when connected up to the hardware SPI pins on a microcontroller. Arduino mega uses digital pins as 50 (MISO), 51 (MOSI), 52 (SCK), and for the CS line, the most common pin is 53 (SS).  Connect the 5V pin to the 5V pin on the Arduino  Connect the GND pin to the GND pin on the Arduino  Connect CLK to pin 13 or 52
  38. 38. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 38 FLOWCHART FOR STEPPERMOTOR ROTATION: Start Initialize the digital 8 & 9 pins as a output pins(LDR o/p) a=digitalRead(8) b=digitalRead(9) c=a-b ? c=0 or c>0 or c<0 Clockwise rotation Anticlockwise rotationNo rotation End C=0 C<0 c>0
  39. 39. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 39 ? sd.begin(53) FLOWCHART FOR SD CARD DATA LOGGING: Start Set pin 53 (chip/ slave select) as a output pin Initialization done Initialization failed Create and open text file in sd card Read or write data to sd card file Close the file End No Yes
  40. 40. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 40 CHAPTER 7 TESTING
  41. 41. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 41 SOLAR PANEL  A solar panel is an assembly of photovoltaic cells. Solar Panel is responsible for harnessing the solar energy and converting it into electrical energy in order to be stored in the battery for providing power to the stepper motor rotation and supply electricity for commercial and residential applications.  The solar panel of 60Watt is used in the project because stepper motor requires 48Watt to rotate which is less than panel output.  Solar panel has been tested for a day being still and then the rotating panel has been tested for voltage and current readings.  The specifications of solar panel is given below DESCRIPTION RATING OpenCircuit Voltage 20 volts DC Output 17 volts Current 3.2 Amperes Power 60Watts Weight 1.5 kg STEPPERMOTOR  The stepper motor is an electromagnetic device that converts digital pulses into mechanical shaft rotation.  Our design includes stepper motor in order to provide stepwise rotation of solar panel.  The upper setup includes solar panel, panel base, supporting structure panel base which will result into the total weight of around 18Kgs.  In order to withstand the weight of upper rotating part and to effective rotation a motor of 20Kgcm is used in the design.
  42. 42. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 42 GEAR BOX  The gear box used in the design to hold the panel in the proper position when there is no power otherwise panel will fall into either of the end. Which also reduces power consumption by the motor.  The gear ratio of 1:14.33 is used in the design, slow movement as the sun doesn’t move so fast within an hour. VOLTAGE DIVIDER CIRCUIT  Voltage divider circuit is used as a voltage sensor. The maximum voltage extracted from the solar panel is 20 V. But the arduino microcontroller board is devised for working on atmost 5 V therefore we are using a voltage divider circuit. CURRENT SENSOR  A current sensor is a device that detects electric current (AC or DC) in a wire, and generates a signal proportional to it. The generated signal could be analog voltage or current or even digital output.  Arduino controller only senses the voltage not current , so we need a current sensor.  ACS712 current sensor used in the design has 185 mV/A output sensitivity.  ACS712 current sensor output is voltage proportional to the corresponding input voltage.
  43. 43. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 43 CHAPTER 8 APPLICATIONS
  44. 44. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 44 8.1 ALTERNATE ENERGYSOURCE The Earth receives an incredible supply of solar energy. The sun, an average star, is a fusion reactor that has been burning over 4 billion years. It provides enough energy in one minute to supply the world's energy needs for one year. In one day, it provides more energy than our current population would consume in 27 years. In fact, "The amount of solar radiation striking the earth over a three-day period is equivalent to the energy stored in all fossil energy sources." Solar energy is a free, inexhaustible resource, yet harnessing it is a relatively new idea. The ability to use solar power for heat was the first discovery. Producing electricity from solar energy was the second discovery. In 1839 a French physicist named Edmund Becquerel realized that the sun's energy could produce a "photovoltaic effect" (photo = light, voltaic = electrical potential). In the 1880s, selenium photovoltaic (PV) cells were developed that could convert light into electricity with 1-2% efficiency ("the efficiency of a solar cell is the percentage of available sunlight converted by the photovoltaic cell into electricity"), but how the conversion happened was not understood. Photovoltaic power therefore "remained a curiosity for many years, since it was very inefficient at turning sunlight into electricity.""Only in the last few decades when growing energy demands, increasing environmental problems and declining fossil fuel resources made us look to alternative energy options have we focused our attention on truly exploiting this tremendous resource." We will enumerate the results of our solar tracker project for both still solar panel and a rotating solar panel so to show that the voltage and current we get by a tracker assembly is much favourable than the still one.
  45. 45. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 45 For constant solar panel 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 1.00 pm 19.0 2.5 1.30 pm 19.0 2.47 2.00 pm 18.9 2.16 2.30 pm 18.6 2.12 3.00 pm 18.3 2.05 3.30 pm 18.15 1.98 4.00 pm 18.03 1.95 4.30 pm 18.0 1.80
  46. 46. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 46 For rotating solar panel east -xº +xº west Angle TIME VOLTAGE(volts) CURRENT(amps) -30 6.00 am 6.3 0.21 -30 6.30 am 10.2 0.36 -25 7.15 am 12.71 0.42 -25 7.30 am 13.03 0.72 -25 7.45 am 13.15 1.09 -20 8.00 am 13.28 1.43 -20 8.15 am 13.59 1.80 -20 8.30 am 13.63 1.80 -15 9.00 am 14.65 1.83 -15 9.20 am 15.5 2.03 -15 9.40 am 17.6 2.1 -10 10.00 am 18 2.15 -10 10.15 am 18.5 2.19 -10 10.45 am 18.7 2.3 -5 11.15 am 18.9 2.49 0 12.0 am 19.0 2.51 0 12.30 pm 19.0 2.53 5 1.00 pm 19.0 2.5 5 1.30 pm 19.0 2.47 10 2.00 pm 18.9 2.16 10 2.30 pm 18.6 2.12 15 3.00 pm 18.3 2.05 15 3.30 pm 18.15 1.98 20 4.00 pm 18.03 1.95 20 4.30 pm 18.0 1.80
  47. 47. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 47 Fig.23
  48. 48. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 48 Fig.24
  49. 49. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 49 8.2 PANEL MEASURING APPARATUS We have also expanded the scope of our project by using it as a measuring instrument for any sized solar panel. What we expect in this kind of application 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. To achieve this we are using ARDUINO breakout board to store the values of voltage and current outputted by the solar panel over an hour throughout a day so that we can concur the power efficiency through the readings. After the readings are stored for a day the user can relate to the outputs and as per his/her requirements it can choose to buy or not to buy the same solar panel. A snapshot of the same can be shown as Fig.25
  50. 50. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 50 CHAPTER 9 CONCLUSION
  51. 51. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 51 9.1 CONCLUSION: With Global Warming constantly affecting the world in numerous ways, it is essential we begin taking care of nature in whatever way possible. Present day technologies stress on being clean and green. Being environmentally friendly, solar power generators and panels are reasonably easy, safe and convenient to install. Hence enhancing the solar powered systems with intelligent trackers proves to be the optimal solution for utilizing the available solar energy. In recent years, the generation of electricity using solar technology has seen a tremendous growth, in particular because of the economic considerations and smooth operation of the solar panels. Even though the initial costs are high, but operation costs and maintenance costs are low. Solar tracking system today offer an innovative method to track the solar insolation and provide economic compatibility of the generation of electric power where grid connections are difficult to setup and costly. The solar tracker can be still enhanced additional features like rain protection and wind protection which can be done as future work. From the design of experimental set up with Micro Controller Based Solar Tracking System Using Stepper Motor If we compare Tracking by the use of LDR with Fixed Solar Panel System we found that the efficiency of Micro Controller Based Solar Tracking System is improved by 30-45% and it was found that all the parts of the experimental setup are giving good results. Solar Energy Advantages 1. Saves you money After the initial investment has been recovered, the energy from the sun is practically FREE. The recovery/ payback period for this investment can be very short depending on how much electricity your household uses.
  52. 52. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 52 2. Environmentally friendly Solar Energy is clean, renewable (unlike gas, oil and coal) and sustainable, helping to protect our environment. It does not pollute our air by releasing carbon dioxide, nitrogen oxide, sulphur dioxide or mercury into the atmosphere like many traditional forms of electrical generations does. Therefore Solar Energy does not contribute to global warming, acid rain or smog. Solar Energy Disadvantages The initial cost is the main disadvantage of installing a solar energy system, largely because of the high cost of the semi-conducting materials used in building one. The cost of solar energy is also high compared to non-renewable utility-supplied electricity. As energy shortages are becoming more common, solar energy is becoming more price-competitive. Solar panels require quite a large area for installation to achieve a good level of efficiency. The efficiency of the system also relies on the location of the sun, although this problem can be overcome with the installation of certain components. 9.2 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.
  53. 53. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 53 BIBLIOGRAPHY: [1] Rizk J. and Chaiko Y. “Solar Tracking System: More Efficient Use of Solar Panels”, World Academy of Science, Engineering and Technology 41 2008. [2] Filfil Ahmed Nasir, Mohussen Deia Halboot, Dr. Zidan Khamis A. “Microcontroller-Based Sun Path Tracking System”, Eng. & Tech. Journal, Vol. 29, No.7, 2011. [3] P.J. Hession and W.J Bonwick , 1984 “Experience with a sun tracker system” Solar Energy, Volume 32, Issue 1, pp 3-11. [4] SOLAR PANEL/TRACKER on Wikipedia.com [5] Gear box ratio and gear box dependent solar tracker on howstuffworks.com
  54. 54. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 54 APPENDIX 1
  55. 55. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 55 A1.1 MILESTONES: Fig.26 JANUARY 2015:  For the solar tracker components design as the solar panel, battery and charge controller were decided for having a prototype design of the project.  Programming was done using PIC BASIC for the rotation of solar panel based on LDR inputs and the motor rotation was checked in with the program.  The mechanical design of the tracker was verified and given for the making. FEBRUARY 2015:  The first model of the tracker was ready for testing but the problem of bearing its own weight and the weight of the solar panel on one shaft was intolerable.  A new design strategy had to be devised for the better implementation of the project.  Also the solar panel chosen was not outputting enough power to compensate for the loss through the motors.  Charge controller of suitable current and voltage compatible to the battery being used and the application to be presented with was decided.
  56. 56. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 56 MARCH 2015:  Unlike the first model design the second design was agreed upon the principles of distributed weight over two assemblies instead of one.  As the first model had to use two motors for dual rotation, so now we had prepared a design that has only one motor and thus reducing the power loss.  Also the motor had to be powered in throughout to keep the solar panel in the same position thus we had decided to use a gear box to hold the weight of the panel after it rotates to a certain angle. APRIL 2015:  The gearbox was completed within the starting of the month and checked for the weight tolerance and rotation of the solar panel.  As the whole system was heavy enough to withhold the panel assembly the base had to be made larger and heavier to provide it with the perfect balance from the ground.  The hardware was assembled completely by the end of the month and was presented in the project exhibition.  The feedbacks of all the students and faculties were duly noted and the possible improvements were decided to be made.  Also to expand the scope of application of our project there was a suggestion to make our project an experimental apparatus for any solar panel to check its practical voltage and current for a day before deciding on buying the product. This improvement gave a new direction to our viewpoint.  For this to be done we had to have a data logging part with the rest of the software assembly which couldn’t be done using PIC thus we switched over to ARDUINO UNO and used its breakout board sd-card interface to make this improvisation. The current and voltage were sensed by a current sensor and then they were logged in a text file. MAY 2015:  The whole system was presented before the project review panel for final remarks and testing.  Final report was documented as a draft for thorough analysis by the project guide.
  57. 57. MaximumSolarAbsorptionusingDual AxisSolarPanel Dept. of ECE,PESIT-BSC 57 A1.2 ACTIVITIES & GANNT CHART: Fig.27

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