M. R. Rahman; M. S. Hossain; S. Shehab Uddin; A. S. M. Ibrahim
Abstract
In this work, a dual-axis automated solar tracker is developed by using two linear motors, four light dependent resistors (LDRs) and two mono crystalline solar panels. The LDRs are placed on the rotating frame where the solar panels are placed to detect the position of the sun and the controller circuit ...
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In this work, a dual-axis automated solar tracker is developed by using two linear motors, four light dependent resistors (LDRs) and two mono crystalline solar panels. The LDRs are placed on the rotating frame where the solar panels are placed to detect the position of the sun and the controller circuit drives the motors to place the frame towards the sun. The controlling unit has been developed using PLC microcontroller. The motor driver circuit has been designed using a code to align the solar panels to a suitable position so that it is exposed to the maximum amount of solar irradiance. The driver circuit receives data from the LDRs and the microcontroller controls the motors to move the panel along its horizontal and vertical axis. To evaluate the performance of the solar tracker, output power of the solar tracker and an identical set of static solar panels set in an optimum fixed orientation are measured from the open-circuit voltage and the short circuit current for two consecutive days. The output power produced by the automatic solar tracker was consistently higher than that by the static solar panel. The energy gain due to using the automatic solar tracker is at highest in the morning and in the afternoon at almost 40%. The lowest value of energy gain is observed during noon at as low as 1%. The average increase in output throughout the day is 24.09%.
U. S. Shehab; R. K. Shoffiuddin; U. S. Nayeem; S. AHM
Abstract
This research paper analyses the current density and power density of a duel chamber microbial fuel cell using different substrate materials for different resistive loads. Sucrose, sugar and starch were treated as substrate and potassium ferricyanide was used as electron acceptor. The separation of the ...
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This research paper analyses the current density and power density of a duel chamber microbial fuel cell using different substrate materials for different resistive loads. Sucrose, sugar and starch were treated as substrate and potassium ferricyanide was used as electron acceptor. The separation of the cathode and anode cell is provided by proton exchange membrane (PEM) in most of the microbial fuel cell (MFC). The most popular proton exchange membranes are nafion, hyflon, zirfon, ultrex CMI-7000 etc. But all of them are not available to use in this part of the world. As an alternate, salt bridge was used in this study as a PEM which is receptive to other ions & chemicals. Different organic materials like sucrose, glucose, starch can be used as substrate as those are available in organic wastage. As the container of bacteria, the sludge of drain of Dhaka was utilized. The voltage and current were measured across 9.81 kΩ and 5.91 kΩ resistors. 716.32 mV was measured as highest voltage across 9.81 kΩ resistor while 4.65 mA/m^2 and 3.09 mW/m^2 were recorded as maximum current density and power density respectively across 5.91 kΩ resistor for sucrose as substrate. The anode chamber was maintained in anaerobic condition. The temperature during these experiments was (22±2)º C.
