Project Solar Tracking System 3l3a3u

CHAPTER-1 INTRODUCTION 1.1 Solar Tracking System As we know, sun is a one of the most important component in this world. Without sun, it is impossible for a human or living creature to live in this world. Humans nowadays feel uncomforted about the global warming situation. Even this kind of situation bring a lot of negative perception, they should have to think it through the positive way. One of the way to reduce the global warming is to reduce the utilizing of electrical voltage and change to a natural voltage source like wind, rain, tides, sunlight and geothermal heats. So, the engineers try to create a new device that can convert the natural energy to an electrical energy like solar for sunlight energy, wind turbines for wind energy, water turbines. The problem that still exists now is the device that invests by an engineer. For example, the solar that many of the s use is only in a one way direction. If the sun located at the direction that is not perpendicular to the solar , the power that can be generate is low compare to the when the sun located exactly perpendicular to the solar . The sun is rotate from east to west but the highest power that can be generate by the solar is when location of sun is perpendicular to the solar . So the power that can be use in the night day is quite short. So, the project that I will do is called „Solar tracking System‟. This is because the sunlight can generate a clean and free power. This project helps for power generation by setting the equipment to get maximum sunlight automatically. Energy crisis is the most important issue in today's world. Conventional energy resources are not only limited but also the prime culprit for environmental pollution. Renewable energy resources are getting priorities in the whole world to lessen the dependency on conventional resources. Solar energy is rapidly gaining the focus as an important means of expanding renewable energy uses. Solar cells those convert sun's energy into electrical energy are costly and inefficient. Different mechanisms are applied to increase the efficiency of the solar cell to reduce the cost. Solar tracking system is the most appropriate technology to enhance the efficiency of the solar cells by tracking the sun. Light dependent resistors are used as the sensors

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of the solar tracker. The designed tracker has precise control mechanism which will provide three ways of controlling system. A small prototype of solar tracking system is also constructed to implement the design methodology presented here. A solar tracker is a device that orients a payload toward the sun. Payloads can be photovoltaic s, reflectors, lenses or other optical devices. Thus the tracking of the sun‟s location and positioning of the solar are important. The goal of this project is to design an automatic tracking system, which can locate position of the sun. The tracking system will move the solar so that it is positioned perpendicular to the sun for maximum energy conversion at all time. Photo resistors will be used as sensors in this system. The system will consist of light sensing system, microcontroller, gear motor system, and a solar . In flat- photovoltaic (PV) applications, trackers are used to minimize the angle of incidence between the incoming sunlight and a photovoltaic . This increases the amount of energy produced from a fixed amount of installed power generating capacity. In standard photovoltaic applications, it is estimated that trackers are used in at least 85% of commercial installations greater than 1MW from 2009 to 2012.The solar s are operating at optimal parameters when they are at the perfect right angle to the sun. Unfortunately this is accomplished only if solar s are rotated by the sun. This is the purpose of this diy solar tracker system.

Figure 1.1 Solar Tracking System 2

Solar energy is rapidly gaining notoriety as an important means of expanding renewable energy resources. As such, it is vital that those in engineering fields understand the technologies associated with this area. My project will include the design and construction of a LM358IC & LDR-based solar tracking system. Solar tracking allows more energy to be produced because the solar array is able to remain aligned to the sun. This system builds upon topics learned in this course. A working system will ultimately be demonstrated to validate the design. Problems and possible improvements will also be presented. At present, there is a great interest towards solving the energy problems facing the world, more especially the third world countries. This has led to research on alternative energy source that would complement the conventional fossil fuel. The alternatives energy sources include; solar, nuclear and wind, but in this research work we focused on solar energy. Solar energy is the energy generated by harnessing the power of the solar radiation. It is the cleanest source of energy whose use can contribute to saving exhaustible energy sources. Photovoltaic s converts the sun‟s radiation to electricity. The amount of power5 available from a photovoltaic is determine by three parameters first, the type and area of the material, secondly the intensity of the sunlight and the wavelength. With advancement in solar technology, parameter one had been fully improved upon and standardized. In this research work, the other two parameter were fully addressed. As this device, „‟solar tracker‟‟ ensures maximum intensity of sun rays hitting the surface of the from sun- rise to sunset. A solar must be able to follow the sun‟s movement to produce the maximum possible power. This is achieved through the designed and implementation of the tracker system, that maintains the orthogonal position with the light source. The device is implemented by integrating it with a 900V inverter and 12V, 100AH battery. The construction of the tracker is made up of two segments, the electrical and the mechanical part respectively. The electrical system consists of PV sensor, a comparator circuit and a battery. The mechanical system consists of the DC motors, worm gears and the frame that housed the entire system. Resistivity and induction tests were carried out on the DC motors to ensure their optimal performance in the construction.

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1.2 Objective of the Project Below are the main objectives of “Solar Tracking System” projects. 1. To design a project that can detect and compare the intensity of light. 2. To design a project that able to move a stepper motor based on the intensity of light and show the direction .

1.3 Project Scope This project is focused to design and build the prototype of solar tracking system that would be a starting point to build the realistic solar tracking system. Therefore, this prototype will cover the scope as followed. Move both direction and total movement that this system can do is 180° • Using LM358IC,stepper motor(bipolar 5 pin),Light Dependant Resistor (LDR) or Photoresistor as a sensor,4-Transisters & 4-Diods to detect and compare the solar intensity of light.

1.4 Problem Statement As we can see, the problem that we can see here is the solar that is use is only in one way direction. Because of this problem, the power that can be generated is low. The second problem is the price for the solar tracking system is very expensive for the family that use more power than usual because they need to install more than one solar to produce enough power. So, this project is to fix the problem that occurs here. This solar tracking system can detect a 180 degree of rotation. So, the solar that can be generating here is very high compare to when the solar can only stay in one direction. So, the families don‟t have to install more than one solar to generate enough power. One solar is enough to produce a lot of power.

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CHAPTER-2 LITERATURE SURVEY AND DETAIL OF COMPONENTS

2.1 Literature Review Solar tracking system project had been widely employed by the other giant company like BP Solar, Yingli Green Energy, Kyocera, Q-Cells, Sanyo, Sharp Solar, Solar World, Sun Power, and Suntech. Now, many people use solar energy or photovoltaic energy as an alternative power because it‟s free and renewable. As we can see now, the payment charge for an electricity had been risen rapidly because the increasing of gas price. Many researchers have tried to find the alternative energy to replace the gas. One of the alternative energy that we can use is photovoltaic energy. Photovoltaic energy is the most promising and popular form of solar energy. In solar photovoltaic‟s, sunlight is actually converted into electricity. Photovoltaic power was first discovered by a French scientist‟s Antoinc Becquerel in 1839. The first working solar cell was successfully made by Charles frits in 1882. It was made of thin sheets of selenium and coated with gold. The use of solar s for generating electricity and heat seems relatively like new development, it has actually been widely used to generate power since early 1900‟s. In 1954 bell laboratory mass produced the first crystal silicon solar cell. The bell PV cell converted 4% of the sun‟s energy into electricity a rate that was considered the cutting edge in energy technology. Scientists continued to reinvent and enhanced on the design of the original silicon cell and were able to produce a solar cell that was capable of putting 20% return electricity rate. In the late 1900‟s as awareness grew in the science community about the effects of global warming and the need for renewable energy sources, scientists continued to refine the silicon PV and by early 2000 they were able to make a solar cell with 24% electricity return. In just seven years scientists were again able to increase the electricity return of silicon solar cell using space age materials. By 2007, modern silicon PV solar cells were operating with 28% electricity return. Each photovoltaic cell produces a small amount of electricity so they are wired together into

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s to provide enough current (D C) power so it must be converted to alternating current (AC) with the aid of an inverter. This is very different from a conventional understanding of solar power as only a way of heating water. Sunlight is made of photons, small particles of energy. These photons are absorbed by and through the material of a solar cell or solar photovoltaic . The photons 'agitate' the electrons found in the material of the photovoltaic cell. As they begin to move (or are dislodged), these are 'routed' into a current. This, technically, is electricity - the movement of electrons along a path. Solar s made of silicon to convert sunlight into electricity. Solar photovoltaic are used in a number of ways, primarily to power homes that are inter-tied or interconnected with the grid. Wire conducts these electrons, either to batteries or to the regular electrical system of the house, to be used by appliances and other household electrical items. In many solar energy systems, the battery stores energy for later use. This is especially true when the sun is shining strongly.

2.2 Components Analysis 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 and increases proportionately on cloudy days. As the majority of the energy is in the direct beam, maximizing collection requires the sun to be visible to the s as long as possible. 2.2.1 LM358 IC Utilizing the circuit designs perfected for Quad Operational Amplifiers, these dual operational amplifiers feature low power drain, a common mode input voltage range extending to ground/VEE, and single supply or split supply operation. The LM358 series is equivalent to one−half of an LM324. These amplifiers have several distinct advantages over standard operational amplifier types in single supply applications. They can operate at supply voltages as low as 3.0 V or as high as 32 V, with quiescent currents about one−fifth of those associated with the MC1741 (on a per amplifier basis). The common mode input range includes the negative supply, thereby eliminating the necessity for external biasing components in many applications. The output voltage range also includes the negative power supply voltage. 6

2.2.1.1 Description The LM358 series consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a single power supply over a wide range of voltages. Operation from split power supplies is also possible and the low power supply current drain is independent of the magnitude of the power supply voltage.

Figure 2.2.1.1 IC LM358

Application areas include transducer amplifiers, dc gain blocks and all the conventional op amp circuits which now can be more easily implemented in single power supply systems. For example, the LM358 series can be directly operated from the standard +5V power supply voltage which is used in digital systems and will easily provide the required interface electronics without requiring an additional ±15V power supply. 2.2.1.2 Features • Internally frequency compensated for unity gain • Large dc voltage gain: 100 Db • Very low supply current drain (500μA); essentially independent of supply voltage • Wide bandwidth (unity gain): 1MHz (temperature compensated) • Input common-mode voltage range includes ground 7

• Differential input voltage range equal to the power supply voltage • Low input offset voltage: 2mV • Wide power supply range: o Single supply: 3V to 32V o Dual supplies: ±1.5V to ±16V • Large output voltage swing: 0V to V+ - 1.5V • SOP-8L packaging • “Green” Molding Compound (No Br, Sb) • Lead Free Finish/ RoHS Compliant (Note 1) 2.2.1.3 Functional Block Diagram

Figure 2.2.1.3 Functional Block Diagram of IC LM358

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2.2.1.4 Pin Descriptions Pin Name

Pin No.

OUTPUT 1

Description

1

Channel 1 Output

INVERTING INPUT 1

2

Channel 1 Inverting Input

NON-INVERTING INPUT 1

3

Channel 1 Non-inverting Input

GND

4

Ground

NON-INVERTING INPUT 2

5

Channel 2 Non-inverting Input

INVERTING INPUT 2

6

Channel 2 Inverting Input

OUTPUT 2

7

Channel 2 Output

V+

8

Chip Supply Voltage

Table 2.2.1.4 Pin Description 2.2.1.5 Application • Eliminates the need for dual supplies • Compatible with all forms of logic • Two internally compensated op amps • Low power drain ideal for battery operation • Allows direct sensing near GND • V OUT can swing to GND 2.2.2 Light Dependant Resistor – LDR A light dependant resistor also know as a LDR, photoresistor, photoconductor or photocell, is a resistor whose resistance increases or decreases depending on the amount of light intensity. LDRs (Light Dependant Resistors) are a very useful tool in a light/dark circuits. A LDRs can have a variety of resistance and functions. For example it can be used to turn on a light when the LDR is in darkness or to turn off a light when the LDR is in light. It can also work the 9

other way around so when the LDR is in light it turns on the circuit and when it‟s in darkness the resistance increase and disrupts the circuit.

Figure 2.2.2 Light Dependant Resistor 2.2.3 Motor Stepper motors are special motors that are used when motion and position have to be precisely controlled. The stepper motor is closely related in design to three-phase AC synchronous motors where an internal rotor containing permanent magnets or a large iron core with salient poles is controlled by a set of external magnets that are switched electronically. A stepper motor may also be thought of as a cross between a DC electric motor and a solenoid. As each coil is energized in turn, the rotor aligns itself with the magnetic field produced by the energized field winding. Unlike a synchronous motor, in its application, the motor may not rotate continuously; instead, it "steps" from one position to the next as field windings are energized and de- energized in sequence. Depending on the sequence, the rotor may turn forwards or backwards. Simple stepper motor drivers entirely energize or entirely de-energize the field windings, leading the rotor to "cog" to a limited number of positions; more sophisticated drivers can proportionally control the power to the field windings, allowing the rotors to position "between" the "cog" points and thereby rotate extremely smoothly. Computer controlled stepper motors are 10

one of the most versatile forms of positioning systems, particularly when part of a digital servocontrolled system. Stepper motors can be rotated to a specific angle with ease, and hence stepper motors are used in computer disk drives, where the high precision they offer is necessary for the correct functioning of, for example, a hard disk drive or CD drive. Only very old hard drives (from the pre-gigabyte era) use stepper motors; newer drives use systems based on voice coils.

Figure 2.2.3 Motor 2.2.4 Transistor Invented in 1948 by Bardeen, Brattain and Shockley .The bipolar junction transistor consists of three regions of semiconductor material. Contains three ading, alternately doped semiconductor regions: Emitter (E), Base (B), and Collector (C) . The middle region, base, is very thin compared to the diffusion length of minority carriers. One type is called a p-n-p transistor, in which two regions of p-type material sandwich a very thin layer of n-type material. A second type is called an n-p-n transistor, in which two regions of n-type material sandwich a very thin layer of p-type material. Both of these types of transistors consist of two p-n junctions placed very close to one another in a back-to-back arrangement on a single piece of semiconductor material. Diagrams depicting these two types of transistors are shown in Fig. 12.1

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Figure 2.2.4 Transistor

2.2.5 Resistors Resistor is an electrical component that reduces the electric current. The resistor's ability to reduce the current is called resistance and is measured in units of ohms (symbol: Ω). If we make an analogy to water flow through pipes, the resistor is a thin pipe that reduces the water flow. In this inverter circuit resistor is used for charging the capacitor and variable resistor is used for adjusting the output frequency to exact 50 Hz Here we use resisters of different specification shown below-

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Figure 2.2.5 Resistor 2.2.6 Rectifier diodes Semiconductor diodes are active devices which are extremely important for various electrical and electronic circuits. Diodes are active non-linear circuit elements with non-linear voltage-current characteristics. Diodes are used in a wide variety of applications in communication systems (limiters, gates, clippers, mixers), computers (clamps, clippers, logic gates), radar circuits (phase detectors, gain-control circuits, power detectors, parameter amplifiers), radios (mixers, automatic gain control circuits, message detectors), and television (clamps, limiters, phase detectors, etc). The ability of diodes to allow the flow of current in only one direction is commonly exploited in these applications. Another common application of diodes is in rectifiers for power supplies. Rectifiers are mainly used in power supplies where an AC signal is to be converted to DC. The DC voltage is obtained by ing the rectifier‟s output through a filter to remove the ripple (AC components). Although, various types of filters (covered in the chapter on Frequency Response) can be used a capacitor .

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Figure 2.2.6 Diode

2.2.7 Variable Resistor (Port) Variable resistors are often called potentiometers, or pots for short, because one very common use for them is as an adjustable voltage divider. For many years they were often called volume controls‟, because another very common use was in adjusting the audio volume produced by amplifiers, radio and TV receivers. Yet another early name for essentially the same component when it was used simply as a variable resistance was rheostat meaning a device to set the flow‟ (of current). Pots are made in a variety of physical forms, and with the actual resistance element made from different materials. Some pots are made for frequent manual adjustment via a control knob, while others are designed to be adjusted only occasionally with a screwdriver or similar tool, for fine tuning of circuit performance. The latter type are usually called „preset‟ pots or trimpots. This generally allows much more convenient setting, but such pots are not as common as the single-turn type because they are rather more expensive.

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Figure 2.2.7 Variable Resister 2.2.8 DC Batteries The battery is an essential component of almost all aircraft electrical systems. Batteries are used to start engines and auxiliary power units, to provide emergency backup power for essential avionics equipment. Batteries operate by converting chemical energy into electrical energy through electrochemical discharge reactions. Batteries are composed of one or more cells, each containing a positive electrode, negative electrode, separator, and electrolyte . Cells can be divided into two major classes: primary and secondary. Primary cells are not rechargeable and must be replaced once the reactants are depleted. Secondary cells are rechargeable and require a DC charging source to restore reactants to their fully charged state. Examples of primary cells include carbon-zinc (Leclanche or dry cell), alkaline-manganese, mercury- zinc, silver-zinc, and lithium cells (e.g., lithium-manganese dioxide, lithium-sulfur dioxide, and lithium- thionyl chloride). Examples of secondary cells include lead-lead dioxide (lead-acid), nickel-cium, nickel-iron, nickel-hydrogen, nickel-metal hydride, silver-zinc, silver-cium, and lithium-ion.

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CHAPTER-3 PROJECT DISCRIPTION

3.1 Solar Tracking System A solar tracker is a device that orients a payload toward the sun. Payloads can be photovoltaic s, reflectors, lenses or other optical devices. Thus the tracking of the sun‟s location and positioning of the solar are important. The goal of this project is to design an automatic tracking system, which can locate position of the sun. The tracking system will move the solar so that it is positioned perpendicular to the sun for maximum energy conversion at all time. Photoresistors will be used as sensors in this system. The system will consist of light sensing system, microcontroller, gear motor system, and a solar .

Figure 3.1 Solar Tracking System

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3.2 Circuit Diagram of Solar Tracking System Using LM358IC

Figure 3.2 Circuit Diagram of Solar Tracking System 3.2.1 Working of Circuit Diagram The heart of the above circuit is two voltage comparators made using LM358 Dual OpAmp. We all know that when the intensity of light falling on a LDR increases, its resistance decreases. Here LDR is connected with a series resistor (R3 & R4), hence when the intensity of light falling on a LDR increases, voltage across corresponding resistor (R3 or R4) increases. The output of the voltage comparator will be high when the voltage at non-inverting terminal (+) is higher than the voltage at the inverting terminal (-). Inverting (-) terminals of both comparators are shorted and connected to a variable resistor (RV1), which is used to set the reference voltage. Thus the sensitivity of both LDRs can be adjusted by varying the 10K pot shown on the left side of the circuit diagram. When the light falls on a LDR increases, voltage at the non-inverting (+) terminal of corresponding comparator increases and its output goes HIGH. 17

3.3 Software used 3.3.1 PCB Deg steps: 1. Design your circuit board, Use PCB wizard software to draw your circuit board. 2. Buy a plain board that is coated with a fine layer of copper on one side from a retailer. 3. Scrub the board with a scouring pad and water to make sure the copper is clean. Let the board dry. 4. Print your circuit board's design onto the dull side of a sheet of blue transfer paper. Make sure the design is oriented correctly for transfer. 5. Place the blue transfer paper on the board with the circuit board's printed design against the copper. 6. Lay a sheet of ordinary white paper over the blue paper. Following the transfer paper's instructions, iron over the white and blue paper to transfer the design onto the copper board. Iron every design detail that appears near an edge or corner of the board with the tip of the iron. 7. Let the board and blue paper cool. Peel the blue paper slowly away from the board to see the transferred design.

Figure 3.3.1 PCB Deg 18

8. Examine the transfer paper to check for any black toner from the printed design that failed to transfer to the copper board. Make sure the board's design is oriented correctly. 9. Replace any missing toner on the board with ink from a black permanent marker. Allow the ink to dry for a few hours. 10. Remove exposed parts of the copper from the board using ferric chloride in a process called etching. a. Put on old clothes, gloves and safety goggles. b. Warm the ferric chloride, stored in a non-corrosive jar and sealed with a noncorrosive lid, in a bucket of warm water. Do not heat it above 115 F (46 C) to prevent toxic fumes from being released. c. Pour only enough ferric chloride to fill a plastic tray that has plastic risers in it to rest the circuit board on. Be sure to do this in a well-ventilated space. d. Use plastic tongs to lay the circuit board face down on the risers in the tray. Allow 5 to 20 minutes, depending on the size of your circuit board, for the exposed copper to drop off the board as it etches away. Use the plastic tongs to agitate the board and tray to allow for faster etching if necessary. 11. Wash all the etching equipment and the circuit board thoroughly with plenty of running water. 12. Drill 0.03 inch (0.8 mm) lead component holes into your circuit board with high-speed steel or carbide drill bits. Wear safety goggles and a protective mask to protect your eyes and lungs while you drill. 13. Scrub the board clean with a scouring pad and running water. Add your board's electrical components and solder them into place.

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3.4 Datasheet of components At the design stage component availability and cost were put into consideration.

S.no 1.

2.

3.

Component Resistors

Variable resistor

Transistors

Rating

Quantity

cost

47 k ohm

1

2 Rs

15k ohm

1

2 Rs

100 k ohm

1

10 Rs

20k ohm

1

10 Rs

BD139

2

10 Rs

BD140

2

10 Rs

4.

Diode

1N4004

4

24 Rs

5.

Battery

12V

1

20 Rs

6.

IC

LM358

1

20 Rs

7.

LDR

10 K

2

20 Rs

8.

Motor

12V, 100rpm

1

180 Rs

Table 3.4 Datasheet of components

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CHAPTER-4 TESTING AND TROUBLSHOOTING 4.1 Testing At the construction or circuit build-up stage various testing were carried out for transistor, diode, resistor, light dependant resistor, motor & battery .Will like to explain some of them here. 4.1.1 Testing of Bipolar Transistor: Transistor can be damaged by heat when soldering or by misuse in a circuit. It you suspect that a transistor may be damaged there are two easy ways to test it. Testing with a multieeter or testing in a simple switching circuit. For this project the first was used. In testing with a multimeter. Use a multimeter or a simple tester (battery, Resistor and LED) to check each pair of leads for conduction. Set a digital multimeter to diode test and an analogue multimeter to a low resistance range. Test each pair of leads both ways (six tests in total).

Figure 4.1.1 Transistor Testing



The base-emitter (BE) junction should behave like a diode and conduct one way only.



The base-collector (BC) junction should behave like a diode and conduct one way only.



The collector-emitter (CE) should not conduct either way. 21

4.1.2 Testing of Light dependant resistor A very good test can do is to check a ldr with multimeter set to the ohmmeter setting. This is a simple test we can do to check whether it is good, open, or shorted and proper ratting. So we take the ohmmeter and place it across the leg of the ldr.

Figure 4.1.2 Testing of LDR

4.1.3 Testing of diode: A very good test you can do is to check a diode with multimeter set to the ohmmeter setting. This is a simple test we can do to check whether it is good, open, or shorted. So we take the ohmmeter and place it across the leads of the diode. The orientation is very important. (a) Anode-Cathode Diode Resistance Test We first take the ohmmeter and place the positive probe on the anode of the diode (the black part of the diode_ and the negative probe on the cathode of the diode (the black strip), as shown above. In this setup, the diode should read a moderately low resistance, maybe a few hundred thousands of ohms.

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Figure 4.1.1 (a) Anode-Cathode Testing of Diode

(b) Cathode-Anode Diode Resistance Test Now take the ohmmeter and switch the probes around so that the positive probe of the multimeter is now on the cathode of the diode and the negative lead on the anode. In this setup now, the diode should read a much higher resistance, well over 1MΩ. A typical reading may, for example, be 2.3MΩ. The multimeter may even indicate 'OL' for an open circuit, since the resistance is so high.

Figure 2.1.3(b) Cathode-Anode Testing of Diode

4.1.4. Testing of Resistor A very good test can do is to check a diode with multimeter set to the ohmmeter setting. 23

This is a simple test we can do to check whether it is good and proper ratting. So we take the ohmmeter and place it across the leg of the resistor.

Figure 4.1.4 Testing of Resistor 4.1.5. Testing of Motor We connected motor with the dc battery and than motor is rotating in proper direction, so motor is good and ok.

Figure 4.1.5 Testing of Motor

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4.1.6. Testing of Battery We connected battery with the digital multimeter. If multimeter is showing desired voltage, so battery is good and ok.

Figure 4.1.6 Testing of Battery

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CHAPTER-5 ADVANTAGES, DISADVANTAGES AND APPLICATIONS

5.1 Advantages • Solar tracking systems continually orient photovoltaic s towards the sun and can help maximize your investment in your PV system. • One time investment, which provides higher efficiency & flexibility on dependency. • Tracking systems can help reducing emissions and can contribute some help against global warming. • Bulk implementations of tracking systems help reduced consumption of power by other sources. • It enhances the clean and emission free power production.

5.2 Disadvantages • Initial investment is high. • It‟s a bit of difficult for servicing, as the systems are not quite popular regionally. • Moving parts and gears which will require regular maintenance. • May require repair or replacement of broken parts over a long run. • It has to be built reliably, against damages caused by heavy rains.

5.3 Applications Solar trackers are devices used to orient photovoltaic s, reflectors, lenses or other optical devices toward the sun. Since the sun‟s position in the sky changes with the seasons and the time of day, trackers are used to align the collection system to maximize energy production. Several factors must be considered when determining the use of trackers.

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Example: Single Axis Tracker used for Solar Photovoltaic (PV) Applications. Example: Single Axis Tracker used for Solar Thermal Parabolic Trough Applications. • It can be used for small & medium scale power generations. • For power generation at remote places where power lines are not accessible. • For domestic backup power systems.

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CHAPTER-6 CONCLUSION

By using this circuit the solar array can be rotated in required direction following the sun path to get maximum energy from the sun. With the help of this Labview program International Journal of Computer and Electrical Engineering, Vol.4, No.1, February 2012 45the efficiency of the solar would be increased. Again use of this technique can capture large amount of solar energy. For this reason the use of the non conventional energy will increase which is very fruitful incident of our future power sector. It is the main contribution that once the simplicity of solar energy system design is understood, engineers and manufactures will provide new system designs that will expand the solar market worldwide. Upon completion of the solar tracker prototype it was tested to ensure it meet design requirements and specifications. It functioned properly in accordance to design specifications. Test showed that power used by tracker system is less than the power gain by tracking the sun accurately. The most important conclusion of this research, is the total cost of construction of the tracker system is very low. This means the system can be mass produced at lower cost and at affordable rate by many communities in the developing countries.

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REFERENCES [1] J. A. Beltran, J. L. S. Gonzalez Rubio, C.D. Garcia-Beltran: Design, Manufacturing and Performance Test of a Solar Tracker Made by an Embedded Control, CERMA 2007, Mexico. [2] O. Stalter, B. Burger, S. Bacha, D. Roye: Integrated Solar Tracker Positioning Unit in Distributed Grid-Feeding Inverters for V Power Plants, ICIT 2009, Australia. [3] M. A. Panait, T. Tudorache: A Simple Neural Network Solar Tracker for Optimizing Conversion Efficiency in Off-Grid Solar Generators, ICREPQ 2008, Spain. [4] A. M. Morega, J. C. Ordonez, P. A. Negoias, R. Hovsapian: Spherical Photovoltaic Cells – A Constructal Approach to Their Optimization, OPTIM 2006, Romania. [5] A. M. Morega, A. Bejan: A Constructal Approach to the Optimal Design of Photovoltaic Cells, Int. Journal of Green Energy, pp. 233-242, 2005. [6] J. Horzel, K. De Clerq: Advantages of a New Metallization Structure for the Front Side of Solar Cells, 13th EC Photovoltaic Solar Energy Conference, , 1995. [7] P. I. Widenborg, G. Aberle: Polycrystalline Silicon Thin-Film Solar Cells on AIT-Textured Glass Superstrates, Advances in OptoElectronics Journal, Vol. 2007. [8] P. A. Basore: Manufacturing a New Polycrystalline Silicon PV Technology, Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion, pp. 20892093, 2006. [9] P. Turmezei: Chalcogenide Materials for Solar Energy Conversion, Acta Polytechnica Hungarica, Vol. 1, No. 2, pp. 13-16, 2004. [10] Technosoft: IBL2403 Intelligent Drive Manual. [11] A.K. Saxena and V. Dutta, “A versatile microprocessor based controller for solar tracking,” in Proc. IEEE, 1990, pp. 1105 – 1109. [12] R. Condit and D. W. Jones, “Stepping motor fundamentals,” Microchip Inc. Publication AN907, pp. 1 – 22, 2004.

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