Axis Sun Tracking Research Articles

Performance comparison of a double-axis sun tracking versus fixed PV system

In the present study, performance results of two double axis sun tracking photovoltaic (PV) systems are analyzed after one year of operation. Two identical 7.9kWp PV systems with the same modules and inverters were installed at Mugla University campus in October 2009. Measured data of the PV systems are compared with the simulated data. The performance measurements of the PV systems were carried out first when the PV systems were in a fixed position and then the PV systems were controlled while tracking the sun in two axis (on azimuth and solar altitude angles) and the necessary measurements were performed. Annual PV electricity yield is calculated as 11.53MWh with 1459kWh/kWp energy rating for 28 fixed tilt angle for each system. It is calculated that 30.79% more PV electricity is obtained in the double axis sun-tracking system when compared to the latitude tilt fixed system. The annual PV electricity fed to grid is 15.07MWh with 1908kWh/kWp for the double axis sun-tracking PV system between April-2010 and March-2011. The difference between the simulated and measured energy values are less than 5%. The results also allow the comparison of different solutions and the calculation of the electricity output.

A Sliding Mode Control for a Sensorless Tracker : Application on a Photovoltaic System

The photovoltaic sun tracker allows us to increase the energy production. The sun tracker considered in this study has two degrees of freedom (2-DOF) and especially specified by the lack of sensors. In this way, the tracker will have as a set point the sun position at every second during the day for a period of five years. After sunset, the tracker goes back to the initial position (which of sunrise). The sliding mode control (SMC) will be applied to ensure at best the tracking mechanism and, in another hand, the sliding mode observer will replace the velocity sensor which suffers from a lot of measurement disturbances. Experimental measurements show that this autonomic dual axis Sun Tracker increases the power production by over 40%.

Optical Performance of Horizontal Single-Axis Tracked Solar Panels

To investigate the optical performance of horizontal single-axis tracked solar panels, a mathematical procedure to estimate daily collectible radiation on fixed, 2-axis and horizontal single-axis tracked solar panels was developed based the solar geometry and monthly horizontal radiation. Results showed that the annual solar gain on a horizontal single-axis tracked solar panel was related to the orientation of the horizontal tracking axis, tracking the sun about the east-west axis was worst to boost the energy collection of tracked panels, and tracking the sun about the south-north axis was best. Results also indicated that the ratio on south-north single-axis tracked solar panels to that with full 2- axis sun-tracking decreased with the increase in site latitude, implying that the horizontal south-north axis suntracking was suitable to be employed in the region with lower geographical latitude.

Sun Tracking Mechanism Effects on Flat Plate Photovoltaic System Performances for Different Step Time and Main Parameters Affecting the Obtained Gains: Case of North Africa and Mediterranean Site

This work is performed to investigate the effect of using different types of sun tracking mechanisms on the flat plate photovoltaic system performances and the main parameters affecting the amount of their output electrical energy as well as those affecting their gains compared to the traditional fixed photovoltaic systems. The evaluation of different systems has been performed on the basis of hourly measured data over a complete one year obtained from Bouzareah location (Mediterranean coastal site). Considering all sky states, the monthly and yearly produced electrical energy by each one of the considered systems as well as the electrical gain of the photovoltaic panel mounted on different sun tracker systems were evaluated. From these latter, it appears that the highest gains obtained are those related to the two axes sun tracker system, which decrease gradually, from the inclined to the vertical rotating axis if the same optimum slope scheme is considered and from seasonal to the yearly optimum slope if the same rotating axis scheme is considered. So, from the obtained results, appears that if also, all sky states conditions were considered, compared to the single axis sun tracking systems, the gain obtained by the two-axis sun tracking system is relatively low and don’t exceed three percent for some cases. On the other hand, is also observed that the quantity of electrical energy produced by the different systems follows a seasonal variation and mainly related to the sun tracker mechanism under consideration, the choice of the panel slope, the availability amount of solar irradiation amount mainly the normal direct component, the day length and from the seasonal variation of the weather conditions.

Optical Performance of Horizontal Single-Axis Tracked Solar Panels

To investigate the optical performance of horizontal single-axis (HA) sun-tracked solar panels, a mathematical procedure to estimate daily collectible radiation on fixed, 2-axis and HA-tracked solar panels was developed based monthly horizontal radiation. Results showed that the annual solar gain on a HA-tracked solar panel was related to the orientation of HA, tracking the sun about the east-west axis was worst to boost the energy collection of solar panels, and tracking the sun about the south-north axis was best. Results also indicated that the ratio of annual collectible radiation on horizontal south-north sun-axis tracked solar panels to that with full 2-axis sun-tracking decreased with the increase in site latitude, implying that the horizontal south-north axis sun-tracking was suitable to be employed in regions with lower geographical latitude

Automatic Two Axes Sun-Tracking System Applied to Photovoltaic System for LED Street Light

This paper presents an electromechanical, two axes sun tracking system based on single chip microcomputer (MCU). According to the path of the sun in the space, the earth coordinate system is chosen to design the tracking device. The whole device consists of one worm-drive and one gear-drive, which is operated by two step motors. The photodiodes are used as photoelectric sensors to detect the pointing of the sun. Eight photodiodes are installed in the diameter hole of the hemispherical surface. The comparative signals produced by the diodes array are performed to judge the orientation of the solar panel. The circuit of the control system based on MCU is demonstrated. The comparative signals may be amplified, A/D converted. After a series of signal processing, the signals are sent to the MCU which will produce the pulse to control the speed and steering of step motors. The sun tracking system is an efficient system for solar energy collection. It has been proved that the sun tracking systems can collect up to 50% more energy than what a fixed panel system collects.

Design, construction and operation of spherical solar cooker with automatic sun tracking system

In this work, the effect of two axes tracking on a solar cooking system was studied. A dish was built to concentrate solar radiation on a pan that is fixed at the focus of the dish. The dish tracks the sun using a two axes sun tracking system. This system was built and tested. Experimental results obtained show that the temperature inside the pan reached more than 93 °C in a day where the maximum ambient temperature was 32 °C. This temperature is suitable for cooking purposes and this was achieved by using the two axes sun tracking system.

Cost comparative study for new water distillation techniques by solar energy using

The aim of this work is to compare the extra added cost of different new water distillation techniques to the cost of extra collected distilled water. The comparison is between; a traditional single slope solar still, a solar still with installed reflecting mirror, a solar still with replacing the flat water with step wise basin, a solar still with a single axis sun tracking system and a solar still with sun tracking system and replacing the flat water basin with step wise basin. It was found that all cases of modifications have an economical effect except one which is the system with sun tracking. The most feasible system is the step wise design, which gave the shortest pay back period of 2.1 years, followed by the system with sun tracking and step wise, which gave the payback period of 3.6 years, followed by the system with reflecting mirrors, which gave the payback period of 4.6 years.

A parabolic solar cooker with automatic two axes sun tracking system

A parabolic solar cooker with automatic two axes sun tracking system was designed, constructed, operated and tested to overcome the need for frequent tracking and standing in the sun, facing all concentrating solar cookers with manual tracking, and a programmable logic controller was used to control the motion of the solar cooker. The results of the continuous test – performed for three days from 8:30 h to 16:30 h in the year 2008 – showed that the water temperature inside the cooker’s tube reached 90 °C in typical summer days, when the maximum registered ambient temperature was 36 °C. It was also noticed that the water temperature increases when the ambient temperature gets higher or when the solar intensity is abundant. This is in favor of utilizing this cooker in many developing countries, which are characterized by high solar insulations and high temperatures. Besides cooking, the proposed cooker could be utilized for warming food, drinks as well as to pasteurize water or milk.

04/02906 Two axes sun tracking system with PLC control: Abdallah, S. and Nijmeh, S. Energy Conversion and Management, 2004,45, (11–12), 1931–1939

04/02906 Two axes sun tracking system with PLC control: Abdallah, S. and Nijmeh, S. Energy Conversion and Management, 2004,45, (11–12), 1931–1939

Developing a multipurpose sun tracking system using fuzzy control

The present work demonstrates the design and simulation of time controlled step sun tracking systems that include: one axis sun tracking with the tilted aperture equal to the latitude angle, equatorial two axis sun tracking and azimuth/elevation sun tracking. The first order Sugeno fuzzy inference system is utilized for modeling and controller design. In addition, an estimation of the insolation incident on a two axis sun tracking system is determined by fuzzy IF-THEN rules. The approach starts by generating the input/output data. Then, the subtractive clustering algorithm, along with least square estimation (LSE), generates the fuzzy rules that describe the relationship between the input/output data of solar angles that change with time. The fuzzy rules are tuned by an adaptive neuro-fuzzy inference system (ANFIS). Finally, an open loop control system is designed for each of the previous types of sun tracking systems. The results are shown using simulation and virtual reality. The site of application is chosen at Amman, Jordan (32° North, 36° East), and the period of controlling and simulating each type of tracking system is the year 2003.

Two axes sun tracking system with PLC control

In this paper, an electromechanical, two axes sun tracking system is designed and constructed. The programming method of control with an open loop system is employed where the programmable logic controller is used to control the motion of the sun tracking surface. An experimental study was performed to investigate the effect of using two axes tracking on the solar energy collected. The collected energy was measured and compared with that on a fixed surface tilted at 32° towards the south. The results indicate that the measured collected solar energy on the moving surface was significantly larger than that on a fixed surface. The two axes tracking surface showed a better performance with an increase in the collected energy of up to 41.34% compared with the fixed surface.

Electricity from the sun: The largest photovoltaic plants in operation in Italy

The Photovoltaic activity in Italy, in last years, has been characterized by an effort focussed in the field of large grid connected power plants. The basic scope of the effort was the investigation of issues arising from the grid connection of such plants, and the identification and validation of satisfactory solutions. It was also necessary to assess the reliability of subsystems and components in MW size and in grid-connected operation. The size of the plants erected was limited by economical reasons. It was large enough, however, to permit easy extrapolation to much larger sizes, such to be significant on the production point of view. Among the plants on service we shall mention first of all the largest one, Serre, 3300 kWp, designed, erected and operated by ENEL. For Serre ANIT has supplied modules for 5 of the nine 330 kW plant segments presently in operation. The tenth segment, with 1 axis sun tracking, is still in the execution phase. Moreover ANIT has designed and erected for private operators large grid connected PV Power Plants.

Aluminum alloy laboratory clamps

In the present study, performance results of two double axis sun tracking photovoltaic (PV) systems are analyzed after one year of operation. Two identical 7.9 kWp PV systems with the same modules and inverters were installed at Mugla University campus in October 2009. Measured data of the PV systems are compared with the simulated data. The performance measurements of the PV systems were carried out first when the PV systems were in a fixed position and then the PV systems were controlled while tracking the sun in two axis (on azimuth and solar altitude angles) and the necessary measurements were performed. Annual PV electricity yield is calculated as 11.53 MW h with 1459 kW h/kWp energy rating for 28 fixed tilt angle for each system. It is calculated that 30.79% more PV electricity is obtained in the double axis sun-tracking system when compared to the latitude tilt fixed system. The annual PV electricity fed to grid is 15.07 MW h with 1908 kW h/kWp for the double axis sun-tracking PV system between April-2010 and March-2011. The difference between the simulated and measured energy values are less than 5%. The results also allow the comparison of different solutions and the calculation of the electricity output.