“HORIZONTL SINGLE AXIS SOLAR TRAKER USING ARDUINO UNO”
Satyam Namdeo, Ritik Rajak, Umesh Kumar, Yogesh Mishra Prof. Manoj Tiwari, (Guide)
Department of Mechanical Engineering,
Gyan Ganga Institute of Technology and Sciences, Jabalpur (M.P.)
Abstract -This project discusses on the development of horizontal single axis solar tracker using Arduino UNO which is cheaper, less complex and can still achieved the required efficiency. For the development of horizontal single axis solar tracking system, five light dependent resistors (LDR) has been used for sunlight detection and to capture the maximum light intensity.
A servo motor is used to rotate the solar panel to the maximum light source sensing by the light dependent resistor (LDR) in order to increase the efficiency of the solar panel and generate the maximum energy. The efficiency of the system has been tested and compared with the static solar panel on several time intervals.
A small prototype of horizontal single axis solar tracking system will be constructed to implement the design methodology presented here. As a result of solar tracking system, solar panel will generate more power, voltage, current value and higher efficiency.
Solar energy is rapidly gaining ground as an important mean of expanding renewable energy use. Solar tracking is employed in order to maximize collected solar radiation by a photovoltaic panel. In this paper we present a prototype for Automatic solar tracker that is designed using Arduino UNO with Wind sensor to Cease Wind effect on panels if wind speed exceeds certain threshold.
The Proposed solar tracker tracks the location of the sun anywhere in any time by calculating the position of the sun. For producing the maximum amount of solar energy, a solar panel must always be perpendicular to the source of light. Because the sun motion plane varies daily and during the day it moves from east to west; one needs two axis tracking to follow the sun's position. Maximum possible power is collected when two axis tracking is done. However, two axis tracking is relatively costly and complex.
A compromise between maximum power collection and system simplicity is obtained by single axis tracking where the plane (North south axis) is fixed while the east west motion is accomplished. This work deals with the design of both single and two axis tracking systems. Automatic trackers is also compared to Fixed one in terms of Energy generated, Efficiency, Cost and System reliability.
1. INTRODUCTION
In this globalization era, demand of electricity keeps on increasing year by year .The demanding of electricity gives an impact on the loss of main resources to produce electrical energy. Mankind have explored more ways and technologies for the production of electrical energy using the renewable energy resources.
Renewable energy is an energy which generate from natural resources which are naturally replenished. Among all the renewable energy resources that have been discovered, solar energy is the most suitable. The solar energy provides light, heat and energy to all living things.
Solar energy is a free energy which does not have any price if using it.
Furthermore, solar energy does not produce any pollution, environmental friendly and endless supplies.
Solar energy is an energy generated by the sun in the form of solar radiation. Solar radiation from the sun is collected and absorbed by the solar panels and convert into electrical energy.
Solar energy shows a great potential for conversion into electrical in Malaysia because it has very high radiation levels.
Despite of solar energy being a good source of energy, there is a need to improve the methods to harness this energy. This can be achieved by using solar tracking system instead of fixed system.
come out with an idea to develop a single axis solar tracker for solar panel.
The circuit is controlled by microcontroller Atmega328P, two dependent resistor (LDR) and a servo motor. The purpose of the research is to observe comparison of voltage reading
between fixed and tracking solar panel.
proposed dual axis tracking method.
Solar panel assemble and connected to a stepper motor to track the sun so that maximum sunlight will be directly shine on the panel at any given time of the day and year. Deals with the design and execution of a solar tracker system dedicated to the PV conversion panels using a single axis solar tracker device to ensures the optimization of the conversion of solar energy into electricity by properly move and turn the PV panel into the real position of the sunlight.
Discuss on the important of using solar tracking system for extracting solar energy. The researcher discussed on mechanism of building an efficient solar tracking system with the help of LabVIEW software.
Discussed on determining the accuracy of solar trackers by measuring the tracker angles. The tracker angles of the the solar trackers were measured under varying conditions. It examines the degree to which the solar tracking system were able to achieve optimal solar angles (optimal accuracy) over the course of a day and under different operating conditions.
Proposed the mechanism of solar tracking which was implemented by the use of an image processing software which combines the effect of sensors and processed image of sun to control the solar panel accordingly. The purposes of this research are to develop a tracking system that control and monitor the movement of solar panel based on the intensity of the light, to measure output voltage, current and power, P=IV and to compare the efficiency increase of a solar system between fixed solar system and solar tracking system.
Energy crisis is one of the most important issues in today’s world.
Conventional energy resources are limited and are one of the primary reason for environmental pollution. The use of renewable energy is becoming increasingly popular. As far as we know solar technologies are emerging very rapidly all over the world because of their eco-friendly current generation and various applications they have. A solar tracker is one of the famous devices used that orients a payload toward the sun. In photovoltaic applications, trackers are
used to minimize the angle of incidence between the incoming sunlight and a photovoltaic panel to maximize the amount of energy produced from PV system.
2. LITERATURE REVIEW
2.1 Solar Energy as a Natural Resources: The matter of getting energy from renewable sources is very relevant today. While in some locations such energy would solve the basic problems, such as the lack of food, medical care, etc., in other locations it would contribute to the solution of such problems like environmental pollution, resource exhaustion, and others. The sources of renewable energy are well known. Those are wind, water, and sun.
Solar energy attracts special attention because it is inexhaustible. However, it is still not used as widely as people wish.
The main problem is how to harness solar energy. While earlier, it was harnessed through the specific location of buildings, for example, with windows faced to the side where there is more sunshine. Now, solar panels are used to harness solar energy.Just a couple of years ago, the efficiency of solar panels was limited. For example, they could transform solar energy only during hours when the sun was shining on them. Now, the technology has improved significantly.
Such elements as a solar actuator and sensors have changed the way solar panels work. Solar actuators move panels to follow the sunlight. Thus, they make solar panels more efficient. Sensors are the elements that tell the actuators where to move the panel.
2.2 Solar Trajectory
Sun path, sometimes also called day arc, refers to the daily and seasonal arc-like path that the Sun appears to follow across the sky as the Earth rotates and orbits the Sun. The Sun's path affects the length of daytime experienced and amount of daylight received along a certain latitude during a given season.
The relative position of the Sun is a major factor in the heat gain of buildings and in the performance of solar energy systems.[1] Accurate location-specific knowledge of sun path and climatic conditions is essential for economic decisions about solar collector area,
orientation, landscaping, summer shading, and the cost-effective use
of solar trackers.
2.3 Solar Traking Platform
A solar tracking system is designed to optimize the operation of solar energy receivers. The objective of this paper is proposing a new tracking system structure with two axis. The success strategy of this new project focuses on the economical analysis of solar energy. Therefore it is important to determine the most cost effective design, to consider the costs of production and maintenance, and operating. The proposed tracking system uses a new solar sensor position with an adaptive feature.
2.4 Solar Traking Control
There are numerous advantages that can be availed with solar tracking control systems by Mitsubishi Electric. There are several features that the solar tracking system utilizes, which help it stand out:
Generates more electricity than stationary counterparts (10 to 25%
more).
The system can calculate the solar azimuth and zenith angles using trigonometric functions.
The system uses real number processing data, for high precision data manipulation, to accurately calculate solar position.
Under PLC to PLC Communication, serial communications and networks allow fast synchronization, maintenance and monitoring of the tracking station.
Analog interface provides precise inclinometer readings for accurate array positioning and inputs for monitoring the wind speed in the
area. For example, with higher than normal wind, then the position of the controller structure is made parallel to the ground to avoid structural damage to PV modules.
System has Resistance Temperature Detectors (RTD) for temperature monitoring.
System has dedicated VFD protocol for advanced panel positioning to continuously monitor panel movement, simplified tracker programming, and reduced tracker downtime during maintenance.
The Robust Security for Program Protection prevents unauthorized access to the solar tracker algorithm.
System has user-defined function blocks and libraries for simple replication of code to reduce tracker programming errors.
It also comes with self-diagnostic systems to monitor internal components to prevent unnecessary downtime, system protection, and overload functions. The self- diagnostics also enable accurate planning for maintenance checks of trackers and help avoid incurring damage to the tracker.
The IP67F panel is an optional compliant solution with a 5-year warranty.
2.5 Literature Study Motivation
This paper shows the potential system benefits of simple tracking solar system using a stepper motor and light sensor.
This method is increasing power collection efficiency by developing a device that tracks the sun to keep the panel at a right angle to its rays. A solar tracking system is designed, implemented and experimentally tested. The design details and the experimental results are shown. XTRACTING useable electricity from the sun was made possible by the discovery of the photoelectric mechanism and subsequent development of the solar cell - a semi- conductive material that converts visible light into a direct current.
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 realisation of fossil fuel's 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 Geo- thermal have all been utilised with varying levels of success.
DIAGRAM
3. PROBLEM FOUND :
Intermittency : One of the biggest problems that solar energy technology poses is that energy is only generated while the sun is shining. That means nighttime and overcast days can interrupt the supply. The shortage created by this interruption would not be a problem if there were low-cost ways of storing energy as extremely sunny periods can actually generate excess capacity.
As the global capacity for solar power continues to rise, nations like Japan and other global leaders in solar energy technology are focusing on developing adequate energy storage to deal with this issue.
Land Use: Another concern is that solar energy may take up a significant amount of land and cause land degradation or habitat loss for wildlife. While solar PV systems can be fixed to already existing structures, larger utility- scale PV systems may require up to 3.5 to 10 acres per megawatt and CSP facilities require anywhere from 4 to 16.5 acres per megawatt.3 4 However, the impact can be reduced by placing facilities in low-quality areas or along existing transportation and transmission corridors.
Scarcity of Materials: Certain solar technologies require rare materials in their production.
This, however, is primarily a problem for PV technology rather than CSP technology. Also, it is not so much a lack of known reserves as much as it is the inability of current production to meet future demand: Many of the rare materials are byproducts of other processes rather than the focus of targeted mining efforts.
Recycling PV material and advances in nanotechnology that increase solar-cell efficiency could both help boost supply, but perhaps finding material substitutes that exist in greater abundance could play a role.
An Environmental Downside:
The one environmental downside to solar technology is that it contains many of the same hazardous materials as electronics. As solar becomes a more popular energy source, the problem of disposing the hazardous waste becomes an additional challenge. However, assuming the challenge of proper disposal is met, the reduced greenhouse gas emissions that solar energy offers make it an attractive alternative to fossil fuels.
4. METHODOLOGY
This section will be focusing on the methods used to develop horizontal single axis solar tracker using Arduino approach. It is divided into three sub-
section which include the specification of components, software design and hardware design.
This step involves material and component selection, hardware installation, and prototyping design. This project consists of using several electronic components to build up the solar tracking mechanism. The main components used are Arduino UNO, light-dependent resistor (LDR), servo motor, and solar panel. This section discusses the specifications of components used.
Arduino Uno R3 is based on the ATmega 328p microcontroller that canexecute instructions in a single clock cycle, and the ATmega16U microcontroller that is managing the USB connection and ICSP bootloader. Arduino UNO consists of 14 digital pins and 6 analog pins where there are 6 pins are used as Pulse Width Modulation (PWM) pins to control the speed of the motor.
This deviceis commonly used in electronic circuit design where it can detect the presence of light.
LDR is made from semiconductor materials such as cadmium sulfide (CdS) and lead sulfide, PbS.It works on the principle of photoconductivity, where the resistance of LDR will be changed when detecting light. A significant drop inthe resistance will occur when the level of light intensity increases.
The solar panel is an electrical device that canconvert light energy from the Sun into electricity by the photovoltaic effect. Electrical parameters such as voltage, current, and resistance will be varying when the solar cell is exposed to sunlight
5. SPECIFICATIONS OF
COMPONENTS
This section discusses the components that used on this research
5.1 Arduino Uno
The Arduino UNO is a micro-controller
board based on the ATmega328. It has fourteen digital input/output pins (of which six of it can be used as PWM outputs), six analog inputs, 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 micro-controller; it can simply connect to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.
Arduino/Genuino Uno is a microcontroller board based on the ATmega328P (datasheet). It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz quartz crystal, 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.. You can tinker with your UNO without worring too much about doing something wrong, worst case scenario you can replace the chip for a few dollars and start over again.
"Uno" means one in Italian and was chosen to mark the release of Arduino Software (IDE) 1.0. The Uno board and version 1.0 of Arduino Software (IDE) were the reference versions of Arduino, now evolved to newer releases. The Uno board is the first in a series of USB Arduino boards, and the reference model for the Arduino platform;
for an extensive list of current, past or outdated boards see the Arduino index of boards.
5.2 Liquid Crystal Display (LCD) : Liquid Crystal Display (LCD) is an electronic display module or screen and has a wide range of applications. It is very basic and very commonly used in many devices and circuits. LCD can display sixteen characters per line and a second
line on the screen (16x2). The LCD will be displayed in a matrix of 5x7 pixels. The specifications of LCD display pins is tabulated.
LCDs are used in a wide range of applications, including LCD televisions computer monitors, instrument panels, aircraft cockpit displays, and indoor and outdoor signage. Small LCD screens are common in LCD projectors and portable consumer devices such as digital cameras, watches, digital clocks, calculators, and mobile telephones, including smartphones. LCD screens are also used on consumer electronics products such as DVD players, video game devices and clocks. LCD screens have replaced heavy, bulky cathode ray tube (CRT) displays in nearly all applications. LCD screens are available in a wider range of screen sizes than CRT and plasma displays, with LCD screens available in sizes ranging from tiny digital watches to very large television receivers.
LCDs are slowly being replaced by OLEDs, which can be easily made into different shapes, and have a lower response time, wider color gamut, virtually infinite color contrast and viewing angles, lower weight for a given display size and a slimmer profile (because OLEDs use a single glass or plastic panel whereas LCDs use two glass panels; the thickness of the panels increases with size but the increase is more noticeable on LCDs) and potentially lower power consumption (as the display is only "on" where needed and there is no backlight).
OLEDs, however, are more expensive for a given display size due to the very expensive electroluminescent materials or phosphors that they use.
Also due to the use of phosphors, OLEDs suffer from screen burn-in and there is currently no way to recycle OLED displays, whereas LCD panels can be recycled, although the technology required to recycle LCDs is not yet widespread. Attempts to maintain the competitiveness of LCDs are quantum dot displays, marketed as SUHD, QLED or Triluminos, which are LCD displays with blue LED backlighting and a Quantum- dot enhancement film (QDEF) that converts part of the blue light into red and green, offering similar performance to an OLED display at a lower price, but the
quantum dot layer that gives these displays their characteristics can not yet be recycled.
5.3 SERVO MOTOR
A Servo Motor is a small device that has an output shaft. This shaft can be positioned to specific angular positions by sending the servo a coded signal. As long as the coded signal exists on the input line, the servo will maintain the angular position of the shaft. If the coded signal changes, the angular position of the shaft changes. In practice, servos are used in radio-controlled airplanes to position control surfaces like the elevators and rudders. They are also used in radio- controlled cars, puppets, and of course, robots.
Servos are extremely useful in robotics. The motors are small, have built-in control circuitry, and are extremely powerful for their size. A standard servo such as the Futaba S-148 has 42 oz/inches of torque, which is strong for its size. It also draws power proportional to the mechanical load. A lightly loaded servo, therefore, does not consume much energy.
A servo motor can be operated with power supply from 4.8V to 6V.
Normally voltage of 5V with operating frequency, f0 = 40Hz is used. Servo motor is used to give accurate angle control such as 45 degrees, 90 degrees. The angle can be hold continuously. It can rotate from 0 degree to 180 degrees when the pulse duty ration changed.
Working of a Servo Motor:
The servo motor has some control circuits and a potentiometer (a variable resistor, aka pot) connected to the output shaft. In the picture above, the pot can be seen on the right side of the circuit board. This pot allows the control circuitry to monitor the current angle of the servo motor.
If the shaft is at the correct angle, then the motor shuts off. If the circuit
finds that the angle is not correct, it will turn the motor until it is at a desired angle. The output shaft of the servo is capable of traveling somewhere around 180 degrees. Usually, it is somewhere in the 210-degree range, however, it varies depending on the manufacturer. A normal servo is used to control an angular motion of 0 to 180 degrees. It is mechanically not capable of turning any farther due to a mechanical stop built on to the main output gear.
The power applied to the motor is proportional to the distance it needs to travel. So, if the shaft needs to turn a large distance, the motor will run at full speed. If it needs to turn only a small amount, the motor will run at a slower speed. This is called proportional control.
5.4 LIGHT DEPENDENT RESISTOR (LDR)
A light dependent resistor is made from semiconductor materials which enable them to have their light sensitive properties. Light dependent resistor is very sensitive towards light. The resistance of light dependent resistor may change over many order when light shine on it. Significance value of the resistance falling as the level of light shine on the light dependent resistor increases.
The lighting sensor is composed the fixed resistor and the light dependent resistor (LDR). Supply voltage is 5V, and the voltage of LDR cannot be connected directly to the controller. So, voltage divider method is applied to read the voltage of LDR. The value of voltage difference between two LDRs is compared to the sensitivity, because the motor cannot be rotated every time on the whole day. The solar tracking system is designed to rotate CW or CCW directions according to the greater level of voltage
when the voltages difference of two LDRs.
When the voltage difference is greater than or not the sensitivity, the motor rotates to its respective direction.
LDR sensor circuit In the above circuit, a complementary resistor with a value of 4.7kΩ is used to get the desired output voltage signals. Regulated voltage supply is 5V. The output voltages are calculated by using the following equation;
For maximum, let R1= RLDR(max)= 1M, Assume,
R2= 4.7k, using voltage divider, Vout=
[R2 /(RLDR+R2 )]×Vcc and the output voltage is 0.02 V.
For midpoint, let R1 = RLDR(mid) = 1k, Assume R2 = 4.7k , the output voltage is 4.12V.
5.5 SOLAR CELL &SOLAR PANEL A solar cell or photo-voltaic cell is an electrical device that converts the energy of light from the sun into electricity by the photo-voltaic effect, which is a physical and chemical phenomenon.
Solar cell is a device whose electrical characteristics such as current, voltage and resistance vary when exposed to the sunlight.
The photovoltaic cell is the basic building block of a photovoltaic system.
The individual cells can vary from 0.5 inches to 4 inches across. One cell can however produce only 1 or 2 watts that is not enough for most appliances.
Performance of a photovoltaic array depends on sunlight. Climatic conditions like clouds and fog significantly affect the amount of solar energy that is received by the array and therefore its performance.
Most of the PV modules are between 10
and 20 percent efficient.
Solar cells can be divided into three broad types, crystalline silicon-based, thin-film solar cells, and a newer development that is a mixture of the other two.
1. Crystalline Silicon Cells: Around 90%
of solar cells are made from crystalline silicon (c-Si) wafers which are sliced from large ingots grown in laboratories. These ingots take up to a month to grow and can take the form of single or multiple crystals. Single crystals are used to create monocrystalline solar panels and cells (mono-Si), while multiple crystals are used for polycrystalline panels and cells (multi-Si or poly c-Si).
These solar cells use an n-type ingot, which are made by heating silicon chunks with small amounts of phosphorus, antimony or arsenic as the dopant. The n-type ingot is coupled with a p-type silicon layer, which uses boron as the dopant. The n-type and p-type ingots are fused to create a junction in a process that was first devised in 1954.
Monocrystalline cells have a distinctive appearance and are often coloured as well as tending to have a cylindrical shape. These cells are cut into shape, which can be wasteful, but do provide the highest levels of efficiency.
Polycrystalline cells do not need to be cut to shape as the silicon is melted and poured into square moulds.
Polycrystalline solar panels are seen as being a mid-range option both in terms of pricandefficiency.
2. Thin Film Solar Cells :Crystalline silicon cells are made from wafers that are just a fraction of a millimetre deep (around 200 micrometers, 200μm), however thin-film solar cells, also called
thin-film photovoltaics are around 100 times thinner. These thin film solar panels and cells are made from amorphous silicon (a-Si), in which the atoms are randomly arranged rather than in an ordered crystalline structure. These films can also be made from cadmium- telluride (Cd-Te), copper indium gallium diselenide (CIGS) or organic PV materials.
These cells are produced by layering photovoltaics to create a module and are the cheapest option for producing solar panels. The cells can be laminated onto windows, skylights, roofing tiles and other substrates, including glass, metals and polymers. However, despite this flexibility, they are not as efficient as regular crystalline silicon cells. Where crystalline silicon cells can produce a 20% efficiency, these thin film cells only reach around 7% efficiency. Even the very best CIGS cells barely reach 12%
efficiency.
3. Third Generation Solar Cells :The latest solar cell technologies combine the best features of crystalline silicon and thin-film solar cells to provide high efficiency and improved practicality for use. They tend to made from amorphous silicon, organic polymers or perovskite crystals, and feature multiple junctions made up from layers of different semiconducting materials.
These cells have the potential to be cheaper, more efficient and more practical than other types of cell, and have been shown to be able to achieve around 30% efficiency (with a perovskite- silicon tandem solar cell)
5.6 SOLAR TRACKING SYSTEM 1.Single axis tracker:
Single axis trackers have one degree of freedom that acts as an axis of rotation.
The axis of rotation of single axis trackers is typically aligned along a true north meridian. It is possible to align them in any cardinal direction with advanced tracking algorithms. A single axis tracker tracks the sun east to west. There are several common implementations of single axis trackers. These include HSAT (horizontal single axis trackers), VSAT (vertical single axis trackers), TSAT (tilted single axis trackers) and PSAT (polar aligned single axis trackers). The orientation of the module with respect to
the tracker axis is important when modeling performance.
2. Dual axis tracker :Dual axis trackers have two degrees of freedom that act as axes of rotation. These axes are typically normal to one another. The axis that is fixed with respect to the ground can be considered a primary axis. The axis that is referenced to the primary axis can be considered a secondary axis. There are several common implementations of dual axis trackers. They are classified by the orientation of their primary axes with respect to the ground. two-axis tracker tracks the daily east to west movement of the sun and the daily declination movement of the sun. Two common implementations are TTDAT (tip-tilt dual axis trackers) and AADAT (azimuth- altitude dual axis trackers)
Some Dual axis trackers are designed by using Light Detecting sensors (LDRs), it consists of two sets of phototransistor sensors, two motors and PIC controller. One set of sensors and one motor is used to tilt the tracker in sun’s east - west direction and the other set of sensors and the other motor which is fixed at the bottom of the tracker is used to tilt the tracker in the sun’s north-south direction. The light sensor’s consists of two LDR’s placed on either side of the panel separated by an opaque plate.
Depending on the intensity of the sun rays one of the two LDR’s will be shadowed and the other will be illuminated. The LDR present in the side, in which the intensity of the sun rays is higher, will generate a stronger signal and the other will generate a weaker signal.
The difference in the output voltage between the two LDR’s will help in the movement of the PV panel in the direction in which the intensity of the sun rays is maximum[4]. but they are not working that exact due to their limitations like Shadow factor, cause if there is Clouds the two sensors will not be illuminated so the panel will not track and also will lose track if the Clouds disappear. The
alternate solution proposed here is Dual axis trackers based on calculating the position of the sun using sun motion equation are more reliable cause it get over the shadowing effect by prediction of the position of the sun and moving the tracker regardless there is shadowing or not. in addition to solving the problem of Wind speed if it exceeds certain Threshold using wind sensor and stopping the system to save the panel and continue tracking if the wind level below this threshold.
6. SOFTWARE DESIGN
Program Flowchart of the System:
Firstly the header files, the variable, input and output pins are considered to initialize. Then the dada from LDRs are read. The difference between the two LDR and sensitivity are compared. If the measured difference between the set of sensors is greater than the sensitivity value, the direction pin on Arduino is HIGH. The motor rotates CW direction. Or the direction pin on Arduino is LOW and the motor rotates CCW direction This section explained the circuit design of light dependent resistor controlling the rotation of the servo motor by using Proteus software. This circuit consists of an Arduino UNO a LCD Display, a servo motor, five units of light dependent resistor (LDR), five units of 10kΩ resistor, a reset button, an on/off button.
7. HARDWARE DESIGN
In the electronic circuit of the proposed testbench. For automatic mode, the microcontroller converts the analogs values of LDR sensors (pins A0 to A3) into digitals. Then it controls two servomotors(up-down and left-right) using two Pulse-Width Modulation (PWM) signals (pins 5and 6) to track the sun. The rotation movements occur in two axes, in azimuth from east to west according to the daily sun's path and in elevation from south to north according to the seasonal sun's path. For manual mode, a potentiometer (pin A4) is used to control the movement of the two servo motors, a push-button (pin 11) is deployed to connect the potentiometer either to up-down servomotor or left- right servomotor. Besides, another pushbutton (pin 12) is used to switch between the two modes. Furthermore, the PV voltage is measured through the analog pin A5 of the Arduino, then the PV current is calculated since the resistor of the load is already known.
Next, the PV current, voltage and power versus time and the actual mode are sent to the computer to present them in real-time on MS Excel.
Electronic circuit of the solar tracker with manual and automatic modes
The LDR sensor circuitry is designed as a voltage divider circuit.
The variation in the light intensity is proportional to the variation of the divider output voltage. The top of the potential divider is 5 V, the ground is at
0 V, and the output of the voltage divider is connected to an analog input of the microcontroller. Subsequently, the Analog to Digital Converter of the microcontroller converts the analog value read by A0 into a digital value between 0 and 1023 because the ADC is coded in 10 bits, and according to this value, it is possible to know the level of light. The value of resistors used in voltage dividers is 330 Ω.
Two 180 degrees servomotors are used. A servomotor to control the solar tracker according to the vertical axis, which is the left-right servomotor.
And a micro servo motor to control the solar tracker according to the horizontal axis, which is the up-down servomotor. The advantage of the servomotor is that we can control its stop, run, the direction of rotation and speed using a single low current wire connected directly to an output of the microcontroller without needing any drivers. The used servo motors are controlled by the Arduino UNO board via 3-wire electrical cable, two wires for supply and one wire for PWM to control its positions.
8. RESULT
This section explained the result of outdoor testing. Outdoor testing has been done to show the functionality of the horizontal single axis solar tracker system towards sunlight.
The testing is done only if the weather is in good condition. Comparison of power, voltage, current and efficiency between static solar panel with fixed angle and solar tracker with variable angles has been taken.
Based on the comparison, solar panel with solar tracking mechanism has higher performance than static solar panel while there is a similar value from 11.00 am until 2.00 pm due to both solar
panels are position horizontally, facing vertically upward and receive the same amount of radiation from the sunlight.
While conducting an outdoor experiment, some disturbances will affect the performance of the solar panel, one of the factors will be the weather condition during the time to collect data. There are different weather conditions such as rainy days, cloudy days, and sunny days in Malaysia. The performance of the solar panel would be affected on cloudy days, as the beam radiation of sunlight will be blocked by cloud and the solar panel may not be able to directly received diffused radiation from the Sun.
This is in agreement with what had been done and in which experimental
studies had been conducted. To compare the performance of solar panels with a tracking mechanism and static solar panel, a solar tracking prototype that was controlled by Arduino had been built. The hardware modeling of the solar tracking mechanism is referenced to the construction of the solar tracking structure discussed by.
An outdoor experiment had been conducted to measure the solar parameters and the result obtained is validated by comparing it with the previous model. Although the value compared is different, but comparison had demonstrated a similar trend which indicates the measured value is obtained in a correct path.
9. DATA ANALYSIS :
The data from the two LDRs are converted to analogue voltages and compared to hour by hour. But there are not much changed in the day. If here is no light, the system is switched off to reduce power consumption. Table 1. shows the comparison of the voltages on cloudy day.
Table 1.The comparison of the voltages on cloudy day
TIME DR 1 Volt DR 2 Volt
08:00Am 3.76 3.88
09:00 Am 3.96 4.22
10:00 Am 4.24 4.52
11:00 Am 4.48 4.72
12:00 Am 4.78 4.75
1:00 Pm 4.69 4.64
2:00 Pm 4.60 4.65
3:00 Pm 4.32 4.36
Table 2. The comparison of the voltages on sunny day
TIME DR 1 Volt DR 2 Volt
08:00Am 1.55 1.61
09:00Am 1.82 1.85
10:00Am 2.40 2.52
11:00Am 2.65 2.71
12:00Am 2.89 3.08
1:00 Pm 3.02 3.14
2:00 Pm 2.75 2.86
3:00 Pm 2.42 2.52
From the data, it can be seen that the voltage from cloudy day is less as twice as the sunny day. But voltage difference of cloudy day is greater than the sunny day.
So the motion of solar panel is infrequently changed in sunny day.
Cost to Install a 1 kW Solar System on a Residential Rooftop:
The average capacity of rooftop systems installed at home ranges from 1 kW to 10 dependingon the availability of ideal roof space and is the permissible capacity allowed by the distribution company
(DISCOM). Most DISCOMs only allow 80% of the sanctioned load. That is, to install a 5 kW system, you need to have a sanctioned load of not less than 6 kW.
Your electricity bills have the details of the sanctioned load mentioned in them. The cost of the rooftop solar systems largely depends on the price of modules and inverters used. An advanced technology module will cost more but is also of premium quality, lasts longer, generates more energy in constrained roof spaces and requires low maintenance
The average cost of a system:
The cost of a 1 kW rooftop solar system ranges from 45,000 to 85,000 excluding the cost of batteries. We are assuming the rooftop solar systems are connected to the grid, and the power is not stored in batteries.
A 5 kW system could cost in the range of 225,000 to 425,000 excluding GST. There could be other costs involved, including constructing an elevated structure or strengthening the roofs where necessary.
The system’s price varies on the brand the consumer chooses. It also depends on the quality of solar panels, inverters, mounting structures, and other equipment used for the system. So, if the consumer wants to go for a cost-effective model, it would cost them around 225,000 – 325,000.
Commercial Solar System – 20kW- 100kW Solar Power Plant Price People are frequently concerned about high electricity costs in commercial sectors. By installing a commercial rooftop on grid power plant, companies can either significantly reduce or eliminate their electricity bill up to 100%
for 25 years or even more. These solar power plants are recommended for business, commercial complexes, school- college, institutes and industry with high energy consumption.
There are various capacities in
commercial solar systems
including 20kW Solar System, 40kW Solar System, 75kW Solar System, and 100kW Solar System. We have discussed their size, area requirement, watt, volt, working, technical specification and cost in this article. So it’s worth spending 10 minutes reading this information and selecting the best
capacity system that meets all your requirements.
A 20kW solar system is ideal for small and medium-sized businesses and organisations. This system is basically an on grid solar system that can generate approximately 80 units per day or 2400 units per month as an average over the year. For installation, a 120-square-meter shadow-free and gap-free area is required. This system’s ROI (return on investment) is also amazing i.e. 3 to 5 years.
Price Range is Rs.9,40,000 – Rs.16,00,000
In medium size manufacturing units and businesses where the per day power requirement is less than or equal to 160 units/day, a 40kW solar system is best.
This system is a complete solar setup with solar panel, solar inverter and other solar accessories.A 40kW solar system can produce up to 160 units/day and 4800 units per month. For installing this capacity solar system 240 sq. meter space (shadow free) is needed. See the detailed specification of 40kW on grid solar system below.
Price Range is Rs.17,60,000 – Rs.31,50,000
A 100kW solar system is a large capacity commercial solar system that is best suitable for large manufacturing units or businesses with high energy usage.
Similar to other capacities solar systems, this 100kW solar system includes solar panels, an on-grid solar inverter, and other solar accessories.This solar system has a massive capacity for generating electricity. It generates 400 units/day and 12000 units/month as an average over the year. Its average payback time period is 3 to 5 years. For installing such a big solar system 600 sq.
meter shadow + gap free area is required.
Price Range is Rs.35,00,000 – Rs.50,00000
1 MW Solar Power Plant:
A solar power plant with a 1MW capacity or more can be considered as a “Ground Mounted Solar Power Plant, Solar Power Station or Energy Generating Station”. These solar power systems produce a large amount of electricity which is more than enough to power any company independently or can subsequently be sold to the government Today, anyone can set up a solar power plant with a capacity of 1KW to 1MW on their land or rooftops. Ministry of New and Renewable Energy (MNRE) and state nodal agencies are also providing 20%- 70% subsidy on solar for residential, institutional, and non-profit organizations to promote such green energy sources. State electricity boards and distribution companies will assist you during the entire process. These incentives/schemes will boost the power generation in India and encourage people to install solar power systems.
Price Range is Rs4.87 Cr. (Approx.)
ADVANTAGES :
Trackers generate more electricity than their stationary counterparts due to increased direct exposure to solar rays. This increase can be as much as 10 to 25% depending on the geographic location of the tracking system.
There are many different kinds of solar trackers, such as single- axis and dual-axis trackers, all of which can be the perfect fit for a unique jobsite. Installation size, local weather, degree of latitude and electrical requirements are all important considerations that can influence the type of solar tracker best suited for a specific solar installation.
Solar trackers generate more electricity in roughly the same
amount of space needed for fixed-tilt systems, making them ideal for optimizing land usage.
In certain states, some utilities offer Time of Use (TOU) rate plans for solar power, which means the utility will purchase the power generated during the peak time of the day at a higher rate. In this case, it is beneficial to generate a greater amount of electricity during these peak times of the day. Using a tracking system helps maximize the energy gains during these peak time periods.
Advancements in technology and reliability in electronics and mechanics have drastically reduced long-term maintenance concerns for tracking systems.
DISADVANTAGES:
Solar trackers are slightly more expensive than their stationary counterparts, due to the more complex technology and moving parts necessary for their operation.
This is usually around a $0.08 –
$0.10/W increase depending on the size and location of the project.
Even with the advancements in reliability, there is generally more maintenance required than a traditional fixed rack, though the quality of the solar tracker can play a role in how much and how often this maintenance is needed.
Trackers are a more complex system than fixed racking. This means that typically more site preparation is needed, including additional trenching for wiring and some additional grading.
Single-axis tracker projects also require an additional focus on company stability and bankability.
When it comes to getting projects financed, these systems are more complex and thus are seen as a higher risk from a financier’s viewpoint.
Solar trackers are generally designed for climates with little to no snow making them a more viable solution in warmer climates. Fixed racking accommodates harsher
environmental conditions more easily than tracking systems.
Fixed tracking systems offer more field adjustability than single-axis tracking systems. Fixed systems can generally accommodate up to 20%
slopes in the E/W direction while tracking systems typically offer less of a slope accommodation usually around 10% in the N/S direction.
10. FUTURE WORK
Firstly, the quality of having a solid, almost unyielding structure should be put as one of the main characteristics of a solar tracker.
Hard and solid material need to be used as the main material for the solar tracker structure in order to withstand extreme weather condition such as strong windy day.
Secondly, build a solar tracker that can be monitored from long range, by adding Global System for Mobile Communication (GSM) or build an application software.
Lastly, maximizing the solar-system energy production and produce more energy by upgrading the single axis solar tracker to dual axis solar tracker. More power means a greater return on the solar investment, and greater energy savings.
11. CONCLUSION
An application of solar tracker using arduino approach has been presented in this study. As a conclusion, firstly the development of tracking system to control and monitor the movement of solar panel based on the intensity of the light is achieved. The solar panel will face the sun perpendicularly to absorb more solar energy.
Secondly, solar tracking systems generate more output during the hours while fixed solar panel installation generates least power. However, shading effect give a slightly impact for solar panel to produce the output value.
Thirdly, the percentage efficiency of the system in energy conversion increase when implemented the tracking system. The efficiency gain varies significantly with altitude and the orientation of a fixed solar panel
installation in the same location.
In this paper we have come to a conclusion that dual-axis solar tracker is more efficient in terms of the electrical energy output when compared to the single axis tracker and fixed system. The gain of the dual-axis tracking system is about 40% compared with the fixed system. also we can't neglect that dual axis tracker is more complex due to the tracking system used so it will be more expensive and less reliable than fixed system. The gain of the single- axis tracker systems is about 28% compared with the fixed system, so a compromise between maximum power collection and system simplicity is obtained.
REFERENCES
1. Sameer Meshram, Sharad Valviand Nilesh Raykar. 2016,―A Cost-effective Microcontroller based Sensor for Dual Axis Solar Tracking‖, ISSN: 2172-038 X,No.14 May 2016.
2. Saeed Mansour, Dr. Wagdy R. Anis, Dr.
Ismail M. Hafez. 2015, ISSN 2277-8616, VOLUME 4, ISSUE 05, MAY 2015.
3. Ceyda Aksoy Tirmikci and Cenk Yavuz.2015,‖
INTERNATIONAL JOURNAL OF SCIENTIFIC
& TECHNOLOGY RESEARCH VOLUME 6, ISSUE 09, SEPTEMBER 2017 ISSN 2277- 8616 89 IJSTR©2017 www.ijstr.org Comparison of Solar Trackers and Application of a Sensor Less Dual Axis Solar Tracker‖,(2015)556- 561doi10.17265/1934- 8975/2015.06.006.
4. Deepthi.S, Ponni.A, Ranjitha.R and R Dhanabal. 2013,―Comparison of Efficiencies of Single-Axis Tracking System and Dual- Axis Tracking System with Fixed Mount‖,ISSN: 2319-5967, Volume 2, Issue 2, March 2013.
5. Agarwal, S., and Pal, S. 2011. ―Design, Development and Testing of a PC based One Axis Suntracking System for Maximum Efficiency.‖ Sensors & Transducers Journal 131 (8): 75-82.
6. Al-Haddad, M. K., and Hassan, S. S. 2011.
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―Sun Tracking System for Productivity Enhancement of Solar Stil.‖ Desalination 220 (1-3): 669-76.
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8. Duarte, F., Gaspar, P. D., and Gonçalves, L.
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