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Need an account? Click here to sign up. Download Free PDF. Ijaems Journal. Alok Deep. A short summary of this paper. Download Download PDF. Translate PDF. It is power demands at different operational conditions. The architecture, molten salt power plants and artificial LDR incorporated on solar panel helps to detect sunlight photosynthesis. Trackers direct solar panels or modules which in turn moves the panel accordingly [2].
The solar toward the sun. In any solar application, the when solar panel is kept fixed. The studied have shown conversion efficiency is improved when the modules are that efficiency of solar panels can be increased to a great continually adjusted to the optimum angle as the sun extent if the solar panels continuously rotate in the traverses the sky. This paper presents the designing of a direction of sun.
Microcontroller and an arrangement of solar tracking system which is based on Arduino UNO LDR sensors can be used for the purpose of tracking the and which provides movement of solar panel in the sun [3].
But the system was less efficient because of the direction of maximum sun light incident. As a result of low sensitivity and disturbance of light dependent which we get more efficient system which is compact, low resistors.
The mechanism of solar tracking was cost as well as easy to use. A new mechanical structure for solar trackers which I. The rotation was intelligently controlled can be harnesses successfully using solar photovoltaic by a pre-programmed 2K microcontroller device PIC cells and photovoltaic effect to convert energy into 18F which provides simple programming strategy electrical energy.
But the conversion efficiency of a through C language. The designed algorithm was based normal PV cell is low. One of the main reason for this is on the measurement of intensity of solar radiation which that the output of PV cell is dependent directly on the was captured by an ultra violet sensitive device known as light intensity and with the position of sun in the sky Pyranometer. The system had been tested and the results changing continuously from time to time, the absorption show very significant impact on the mechanical design, efficiency of an immobile solar panel would be controlling algorithm and also the cost of the significantly less at certain time day and year, for the development.
So to maximize the energy generation and The main aim of the proposed system is to develop a cost improve the efficiency solar trackers are required. Block diagram of complete system is shown in Fig. Researchers concluded that embedding the tracking system with solar www. Arduino projects can be stand- alone or communicate with other software applications running on a computer and other types of hardware.
The history of solar energy is as old as humankind. In general, solar energy is radiant light and heat from the sun harnessed using a range of technologies such as photovoltaic and concentrator. In the last two centuries, we started using Sun's energy directly to make electricity. In , Alexandre Edmond Becquerel discovered that certain materials produced small amounts of electric current when exposed to light.
In , When William Grylls Adams and his student, Richard Evans Day, discovered that an electrical current could be started in selenium solely by exposing it to light, they felt confident that they had discovered something completely new.
Light, Einstein discovered, contains packets of energy, which he called light quanta. They saw that the more powerful photons carry enough energy to knock poorly linked electrons from their atomic orbits in materials like selenium. When wires are attached, the liberated electrons flow through them as electricity. After years of experiments to improve the efficiency and commercialization of solar power, solar energy gained support when the government used it to power space exploration equipment in The first solar-powered satellite, Vanguard 1, has traveled more than , revolutions around Earth in the 50 years.
Consequently, in and first solar parks and retractable RV solar panels are created respectively. A solar cell also called a photovoltaic cell is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect. A solar panel is a set of solar photovoltaic modules electrically connected and mounted on a supporting structure. The structural member of a module can either be the top layer or the back layer.
Electrical connections are made in series to achieve a desired output voltage and in parallel to provide a desired current capability. Several types of solar cells are available. Their efficiency is Three ways of increasing the efficiency of the solar panels are through increase of cell efficiency, maximizing the power output and the use of a tracking system.
Maximum power point tracking MPPT is the process of maximizing the power output from the solar panel by keeping its operation on the knee point of P-V characteristics.
MPPT technology will only offer maximum power which can be received from stationary arrays of solar panels at any given time [6]. Automatic solar tracker increases the efficiency of the solar panel by keeping the solar panel aligned with the rotating sun. Shanmugam et al. Rong-Jong Wai et al. Cemil Sungur had given the electromechanical control system of a photovoltaic PV panel tracking the sun on the axis it moved along according to its azimuth angle in Yeong-Chau, et al.
Wilamowski and Xiangli, A few design methodologies of solar tracking system have been proposed in recent days. With the growing demand for alternative and eco-friendly energy that significantly reduces carbon emissions around the world, many major countries have been rapidly increasing the capacity of their solar power facilities and other renewable energy installations over the past few years.
Within global renewable energy installations, solar power plants have enjoyed the fastest growth in volume over the past few years. Thanks to the vast availability and certainty of sunlight, solar power projects have outperformed other forms of renewable energy sources such as wind and geothermal. Moreover, with the advancements in technologies, including concentrated solar power generation techniques, and a decline in prices of PV modules, solar energy has become the most cost-effective source of renewable energy.
A total 75 GW of new installations were added to the global solar energy capacity in The largest increments in were recorded in China Japan provided the third largest addition 8.
China also leads in terms of cumulative installed capacity Japan Alternative energy is synonymous with new, renewable and non-conventional forms of energy. Traditional source of energy includes biomass fuels particularly fuel wood, agricultural residues and animal dung used in the traditional way, which is direct combustion.
Commercial sources of energy are fossil fuels and electricity. When it comes to solar energy, Nepal, being located in favorable latitude, receives ample solar radiation. Today there are basically two major applications of solar energy: thermal and electrical.
Solar water heaters and solar dryers are the two main types of solar thermal devices used under thermal application. Of these, solar water heaters are popular in Hilly and Terai region.
While nationwide survey revealed that three types of solar drying systems were in common use: cabinet type for domestic use, racks type for commercial, and tunnel type for industrial purposes [13]. The other uses of solar energy are for water pumping for drip irrigation and drinking, which appears to be technically and economically feasible.
On the other hand, the solar cooking is not effective because of the trends, and traditional eating and cooking habits using food cooked with kerosene and biomass products. While the energy demand is So solar PV should be developed as an alternative to hydropower. As on average, Nepal has 6. This energy generated is more than energy required for fulfilling the whole energy demand of the world.
The total estimated world energy demand at present is about 13TW. If we use just 0. The mission of AEPC is to make renewable energy mainstream resource through increased access, knowledge and adaptability contributing to the improved living conditions of people in Nepal. In Nepal, solar PV systems can be categorized into four types based on their application areas: solar home systems SHS , solar lantern, community solar PV systems and institutional solar PV system.
Currently over , household solar home systems with capacity of 10—40 Wp. Solar lantern popularly known as Solar Tuki or Tukimara has module size between 2. Over , solar lanterns have been installed by AEPC so far. Even individual solar PV panel between from Wp and 40 kWp are used for solar PV powered water pumping system, especially for drinking water and irrigation purposes for community in Nepal. Also, about solar PV systems have been installed of capacity between 34 Wp and 6.
The majority of these systems were installed in the mid and far- western regions. Installment of PV in different area has been increasing at the rate of 20 percent every year. Even NEA is aiming for an energy mix of , in which 85 per cent of the energy is generated through hydropower and 15 per cent through solar projects. The government has targeted to complete the project within a year and build solar plants with a total installed capacity of MW within the next five years.
A combination of political will, investments in renewable technologies and solid legal framework, however, is a must. Dual axis solar tracking system can be an effective way to increase the efficiency of solar cells. The devastating problem on both biotic and abiotic components of our home i. The natural gift like fossil fuels, woods, etc. For people, due to its more efficiency and less harmful impacts dual axis solar tracking system might be good decision for the intermediate future.
So, this project can practically demonstrate effect of this variation to people. To design and fabricate a dual axis PV system that tracks the sun path. To study different solar parameters and methods of harvesting solar energy. To understand the working mechanism of PV module and tracking system. Si used as the major component of solar panels, which is maximum Unless highly efficient solar panels are invented, the only way to enhance the performance of a solar panel is to increase the intensity of light falling on it.
MPPT technology will only offer maximum power which can be received from stationary arrays of solar panels at any given time. The technology cannot however increase generation of power when the sun is not aligned with the system.
Because the position of the sun changes during the course of the day and season over the year. So, the implementation of a solar tracker is the best solution to increase energy production. Some researchers have conducted various studies to establish the optimal degree of tilt of a solar panel to increase the output power. Currently, there are two main types of solar trackers: the one axis and two axes. This allows the panels to arc from east to west, tracking the sun as it rises, travels across the sky, and sets.
Dual-axis trackers have two degrees of freedom as shown in Fig 4 [23], that act as axes of rotation, aligned with North-South and with East-West, giving them a wide range of position options. So, in order to accurately follow the sun, the two-axis tracking is required as solar azimuth angle as well as solar altitude angle of sun varies in two axis all the time [23].
This optimizes maximum power from the PV system over a day than non-tracking system. Figure 4 :Variation in trajectory of sun from winter to summer The dual axis tracking system is uniquely designed on sensor-based technology avoiding the need for manual programming time to time.
The major components of the system are: 1. PV module 2. Servo motors 3. Light sensors 4. Arduino UNO 5. Battery 6. Inverter 7. AC or DC loads 8. Halogen light System consists of two portion mechanical and electrical system.
In mechanical system, a solar panel is fitted in support, motor and shaft. While the electrical system consists of Sensors, microcontroller and battery. Four sensors detect the intensity of light, which are further connected to the microcontroller circuit Arduino. Then the combined mechanism of motors and shaft rotates the PV panel in the direction of the sun.
Here the microcontroller and motors are operated through the external battery. The flow chart of the whole system is shown in Fig 5. When it comes to thermal use, it is mainly used for water heating and heat sources to different types of concentrator for various heat application.
They can be used in any climate, and the fuel they use: sunshine, is free. Working of solar water heating systems include storage tanks and solar collectors. There are two types of solar water heating systems: active, which have circulating pumps and controls, and passive, which don't.
Though slightly more expensive, active systems offer several advantages. They work well in climates where it rarely freezes. This heats the water that then flows into the home. They are popular in climates prone to freezing temperatures. However, passive systems can be more reliable and may last longer. They also work well in households with significant daytime and evening hot-water needs. The collector must be installed below the storage tank so that warm water will rise into the tank.
These systems are reliable, but contractors must pay careful attention to the roof design because of the heavy storage tank. They are usually more expensive than integral collector-storage passive systems. But we may need higher temperature for different heating purpose. So, various types of concentrator are designed to generate a required amount of heat and temperature in a surface. Different types of concentrator with their temperature production and principle of operation are shown in table.
Different types of solar cells are developed and developing to increase their efficiency. Different parameters regarding photovoltaic module are described below: 1 PV CELLS A solar cell is an electronic device which directly converts sunlight into electricity. Light shining on the solar cell produces both a current and a voltage to generate electric power. The electron then dissipates its energy in the external circuit and returns to the solar cell. A variety of materials and processes can potentially satisfy the requirements for photovoltaic energy conversion, but in practice nearly all photovoltaic energy conversion uses semiconductor materials Figure 7: Photo electric effect in PV cell in the form of a p-n junction.
The basic working can be seen from the fig 7. The generation of current in a solar cell, known as the "light-generated current", involves two key processes. The first process is the absorption of incident photons to create electron-hole pairs. Electron-hole pairs will be generated in the solar cell provided that the incident photon has an energy greater than that of the band gap. However, electrons in the p-type material , and holes in the n-type material are meta- stable and will only exist, on average, for a length of time equal to the minority carrier lifetime before they recombine.
If the carrier recombines, then the light-generated electron-hole pair is lost and no current or power can be generated. A second process, the collection of these carriers by the p-n junction, prevents this recombination by using a p-n junction to spatially separate the electron and the hole. The carriers are separated by the action of the electric field existing at the p-n junction.
If the light-generated minority carrier reaches the p-n junction, it is swept across the junction by the electric field at the junction, where it is now a majority carrier. If the emitter and base of the solar cell are connected together i. The ideal short circuit flow of electrons and holes at a p-n junction. Minority carriers cannot cross a semiconductor-metal boundary and to prevent recombination they must be collected by the junction if they are to contribute to current flow.
The collection of light-generated carriers does not by itself give rise to power generation. In order to generate power, a voltage must be generated as well as a current. Voltage is generated in a solar cell by a process known as the "photovoltaic effect". The collection of light-generated carriers by the p-n junction causes a movement of electrons to the n-type side and holes to the p-type side of the junction. Under short circuit conditions, there is no buildup of charge, as the carriers exit the device as light- generated current.
However, if the light-generated carriers are prevented from leaving the solar cell, then the collection of light-generated carriers causes an increase in the number of electrons on the n-type side of the p-n junction and a similar increase in holes in the p-type material. This separation of charge creates an electric field at the junction which is in opposition to that already existing at the junction, thereby reducing the net electric field.
Since the electric field represents a barrier to the flow of the forward bias diffusion current, the reduction of the electric field increases the diffusion current. A new equilibrium is reached in which a voltage exists across the p-n junction. The current from the solar cell is the difference between IL and the forward bias current.
Under open circuit conditions, the forward bias of the junction increases to a point where the light- generated current is exactly balanced by the forward bias diffusion current, and the net current is zero. The voltage required to cause these two currents to balance is called the "open-circuit voltage". The light has the effect of shifting the IV curve down into the fourth quadrant where power can be extracted from the diode. Without the illumination, a solar cell has the same electrical characteristics as a large diode.
When the light shines on the cell, the I-V curve shifts as the cell begins to generate power. Fig 8 shows the IV- curve of solar cell. Short-circuit current The short-circuit current is the current through the solar cell when the voltage across the solar cell is zero i.
Usually written as ISC, the short-circuit current. The short-circuit current is due to the generation and collection of light-generated carriers and it is the largest current which may be drawn from the solar cell. Open-circuit voltage The open-circuit voltage, Voc, is the maximum voltage available from a solar cell, and this occurs at zero current.
The open-circuit voltage corresponds to the amount of forward bias on the solar cell due to the bias of the solar cell junction with the light- generated current.
Voc depends on the saturation current of the solar cell and the light- generated current. The higher the Pm, the better is the cell. It is measured in watts. A solar cell can operate at many current and voltage combinations, but a solar cell will produce maximum power only when operating at certain current and voltage. Current at maximum power point Im This is the current which solar cell will produce when operating at maximum power point. The Im is always lesser than ISC.
Voltage at maximum power point Vm This is the voltage which solar cell will produce when operating at maximum power point. The Vm is always less than VOC. Fill Factor FF The "fill factor", more commonly known by its abbreviation "FF", is a parameter which, in conjunction with Voc and Isc, determines the maximum power from a solar cell. The FF is defined as the ratio of the maximum power from the solar cell to the product of Voc and Isc. Graphically, the FF is a measure of the "squareness" of the solar cell and is also the area of the largest rectangle which will fit in the IV curve.
Solar cell efficiency Efficiency is defined as the ratio of energy output from the solar cell to input energy from the sun.
In addition to reflecting the performance of the solar cell itself, the efficiency depends on the spectrum and intensity of the incident sunlight and the temperature of the solar cell. Therefore, conditions under which efficiency is measured must be carefully controlled in order to compare the performance of one device to another.
Terrestrial solar cells are measured under AM 1. The voltage of a PV module is usually chosen to be compatible with a 12V battery. An individual silicon solar cell has a voltage of just under 0.
Taking into account an expected reduction in PV module voltage due to temperature and the fact that a battery may require voltages of 15V or more to charge, most modules contain 36 solar cells in series. This gives an open-circuit voltage of about 21V under standard test conditions, and an operating voltage at maximum power and operating temperature of about 17 or 18V.
The remaining excess voltage is included to account for voltage drops caused by other elements of the PV system, including operation away from maximum power point and reductions in light intensity. Also, we can connect cells in parallel for higher charging current. Array may consist of both series and parallel connection, which improves both the system voltage and charging current.
Figure Pictorial representation from solar cell to solar array 2. Or when, electrical parameters of one solar cell are significantly altered from those of the remaining devices. This in turn can lead to highly localized power dissipation and the resultant local heating may cause irreversible damage to the module. These increases in temperature have a major impact on the PV module by reducing its voltage, thereby lowering the output power. The operating temperature of a module is determined by the equilibrium between the heat produced by the PV module, the heat lost to the environment and the ambient operating temperature.
The heat produced by the module depends on the operating point of the module, the optical properties of the module and solar cells, and the packing density of the solar cells in the PV module. While the heat is lost to surrounding by three main mechanisms of heat loss: conduction, convection and radiation.
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