China
Africa
Explore chapters and articles related to this topic
Spectrally Selective Solar Absorbers and Optical Reflectors
Published in Ashutosh Kumar Dubey, Amartya Mukhopadhyay, Bikramjit Basu, Interdisciplinary Engineering Sciences, 2020
Ashutosh Kumar Dubey, Amartya Mukhopadhyay, Bikramjit Basu
A Stirling Dish is a parabolic dish-shaped concentrator similar to the shape of a satellite, which concentrates the solar rays exactly onto the focal point of the parabolic dish where a receiver is placed. In order to reduce the fabrication cost, the large dish is usually made of a larger number of smaller mirrors, which forms a shape of parabola. Generally, a two axes solar tracker is used to focus the solar radiation throughout the day. This system concentrates the entire sunlight into a point and hence the temperature rises at the focal point drastically and eventually the conduction of heat increases the temperature of the gas flowing through the receiver. As a result, at high temperature, the gas expands, and this expansion is used to drive a piston inside a cylinder. The movement of the piston serves as the source of energy to produce electricity. The combination of receiver, engine, and generator is considered as a single unit, which is placed at the focal point of the parabolic dish. The size of the receiver for the parabolic dish is small.31 The major advantage of using an assembly of mirrors32,33 is to reflect and to focus the solar radiation onto desired position, which enables to heat up the HTF, such as molten salt, steam, oil, and compressed air.34,35
Harvesting Solar Energy: Fundamentals and Applications
Published in Prasenjit Mondal, Ajay K. Dalai, Sustainable Utilization of Natural Resources, 2017
Syed Shaheer Uddin Ahmed, Sayedus Salehin, Md. Mustafizur Rahman, A. K. M. Sadrul Islam
The sun’s trajectory is a function of the geographical location, time of day, and season. Thus, for a PV to have optimal input from the sun throughout the day is difficult, since best output is achieved when the direct radiation is incident to the normal of the solar panel. Thus, to overcome this issue, the concept of solar tracking is developed. The solar tracker, in contrast to a static solar system, follows the sun’s trajectory and ensures that the solar panels are positioned for maximum exposure to sunlight. The tracker can be operated only in one axis, or it can have two-axis rotational freedom. Two-axis tracking systems move a surface always into an ideal position; however, two-axis tracking systems are relatively complicated, and thus, one-axis tracking systems are preferred in some instances. It has been estimated that static solar system would use about 40% more modules than a two-axis tracking system for equal annual energy (Gay et al. 1982). More detailed studies show that during days with high direct irradiation, tracking can achieve energy gains over horizontal orientation in the order of 50% in summer and up to 300% in winter, depending on the latitude of the location.
Atmosphere Monitoring Using Methods of Absorption of Electromagnetic Radiation—Fourier Transform Infrared Spectroscopy
Published in Ghenadii Korotcenkov, Handbook of Humidity Measurement, 2018
Exterior view of the station using a FTIR spectrometer for monitoring the atmosphere is shown in Figure 4.9. As a rule, the ground-based FTIR experiment consists in a high precise solar tracker that captures the direct solar light beam and couples it into a high resolution FT spectrometer. The high precision solar tracker is controlled by a combination of astronomical calculations and a solar quadrant sensor, or more recently by a digital camera (Gisi et al. 2011), for active tracker control.
Internet of Things Based Horizontal Axis Tracking Solar Panel Performance Evaluation
Published in Electric Power Components and Systems, 2023
The sun’s position is detected using sensors: A horizontal axis solar tracker typically uses light sensors or photovoltaic cells to detect the sun’s positions in the sky. These sensors estimate the azimuth and elevations angle of the sun by detecting the angle of reflections of the sun’s beams. The solar panel’s position is changed: The solar panel’s orientation is changed to maximize its reach of sunlight after the location of the sun has been determined. To track the sun’s path across the sky, a vertical rotation of the solar panel along an axis at the center is used. The angle of rotation is calculated using trigonometry: Trigonometry is used to determine the needed rotational angle to change the orientation of the solar panel. The angle of rotation may be calculated using the equation below: where:θ = the angle of rotation required to adjust the solar panel’s orientationφ = the latitude of the location where the solar panel is installedδ = the declination angle of the sun, which changes throughout the yearω = the hour angle of the sun, which changes throughout the day.
Design of FOPID Controller Using BBBC via ZN Tuning Approach: Simulation and Experimental Validation
Published in IETE Journal of Research, 2022
A solar tracker is used to track the position of the sun across the sky to compensate the error between the sun position and the payload, thereby maximising solar energy output. Solar trackers can be categorised into single-axis and dual-axis solar tracker. In a single-axis tracking system, the tilt angle is fixed and azimuth angle is varied throughout the day, whereas in a dual-axis tracking system both the tilt angle and the azimuth angle are varied. In this work, optimal FOPID is designed for the position control of a dual axis solar tracker by using the proposed approach. Both the tilt angle and azimuth angle are controlled by DC motors and the control of the motors is implemented by FOPID controller which is tuned using BBBC algorithm. We also assume similar type of DC motors for both the axes of a solar tracker.
Design of Active Disturbance Rejection Controller Variants for Solar Tracker System
Published in IETE Journal of Research, 2022
In a solar energy power plant, the essential component is solar tracker panel, which contains an array of photovoltaic (PV) cells. Different types of solar tracker panels are used nowadays to absorb the incident solar energy. They can be a time based, passive and active solar trackers. Out of these solar trackers, the active solar trackers are further classified into two categories. First one is single axis and second is dual axis solar tracker. Only one axis is allowed to vary in single axis sun tracker, while other is kept fixed. So, it has only single degree of freedom (SOF). In dual axis solar tracker, both azimuth angle and tilt angle can vary and so, it has dual degree of freedom (DOF). Passive solar tracker uses two twin cylindrical tubes and a fluid is filled under partial pressure [7]. Its working is based on the principle of imbalanced weights of both cylinders. As, the intensity of solar light varies during the day and so, the weight and pressure of the cylinders also vary and the solar panel rotates accordingly. Although, passive solar trackers are simple and less expensive, however, they seldom attract the consumers because of low efficiency [8]. In time-based solar tracker system, first the position of sun is recorded daily, monthly or yearly basis and further, recorded data is programmed using the controller for upcoming positions. Many researchers compared the efficiency of solar tracker panel and fixed panel, on the basis of output power, and observed that solar tracker system held better output power than the physically fixed photo voltaic (PV) system under different atmospheric conditions like cloudy, partially clear and clear sky [9]. The efficiency is improved to 13%, 14% and 18%, respectively.