Partha Das Purkaistha1, Harkishen Singh2, Arvind CV3
Faculty of Engineering, Architecture & Built Environment UCSI University, Kuala Lumpur, Malaysia email@example.com
Abstract- Energy development is the ongoing effort to provide abundant and accessible energy, through knowledge, skills and constructions. Solar energy is rapidly advancing as an important means of renewable energy resource. More energy is produced by tracking the solar panel to remain aligned to the sun at a right angle to the rays of light. This paper attempts to describe in detail the design and prototype for solar tracking system. The solar tracking system is designed and built using a simple mechanical structure using with a stepper motor, light sensor and a control method. The control circuit for the solar tracker is based on a PIC16F877A microcontroller (MCU). This is programmed to detect the sunlight through the Light sensor and then actuate the motor to position the solar panel where it can receive maximum sunlight.
Keywords: PIC, MCU, Solar energy, Light sensor, Renewable energy.
The world trend nowadays is to find a non-depletable and clean source of energy. Non-renewable energy, obtained from exhaustible fossil fuels, is no more satisfactory to many nations. Not only the resources (coal, oil & natural gas) are subject to be severely reduced, but also they are considered to be non-secure; wars and politics afflict its availability and cost. Moreover many environmental organizations address this energy production scheme as the main contributor to pollution and global warming. For a long time, it has been thought that atomic energy would be a solution for the growing energy problem, but in recent times solar energy has proved to be an efficient, more secure and safe way of providing energy. Concepts related to the solar energy have constantly been under heavy research and development. The basic objective is to optimize the energy produced from photovoltaic cells, by making the overall systems more efficient and cost effective. Most solar panels are statically aligned. They have a fixed position at a certain angle towards the sky. Therefore, the time and intensity of direct sunlight falling upon the solar panel is greatly reduced, resulting in low power output from the photovoltaic (PV) cells. From this background, we see the need to maintain the maximum power output from the panel by maintaining an angle of incidence as close to 0° as possible. By tilting the solar panel to continuously face the sun, this can be achieved. This process of sensing and following the position of the sun is known as Solar Tracking system.
II. SYSTEM OVERVIEW
The design of Solar Tracker is to develop and implement a simplified diagram of a horizontal-axis and active tracker method type of solar tracker fitted to a solar panel. A solar panel along with the direction of sunlight; it uses a gear motor to control the position of the solar panel, which obtains its data from a PIC16F877A microcontroller. Two light dependent resistors (LDR) are used for each degree of freedom. LDRs are basically photocells that are sensitive to light. Software will be developed which would allow the PIC to detect and obtain its data from the two LDRs and then compare their resistance. The two LDRs will be positioned in such a way, so that if one of the two comes under a shadow, the MCU will detect the difference in resistance and thus actuate the stepper motor to move the solar panel at a position where the light upon both LDRs are equal. A simple mechanical structure has been constructed for this by using aluminium channel. Power MOSFET has been to design the driver circuit of stepper motor. A 12V lead Acid battery has been used to power up the motor and store the energy from solar panel. Charge controller control the charging of batter. Figure 1 shows the block diagram representation of the tracking system...