Design and implementation of a transistorized bi-controlled based utility-connected battery charger for underdeveloped nations

This paper presents a transistorized bi-controlled based utility-connected battery charger to address the problem of erratic public power supply in underdeveloped nations. In this study, a utility battery charger was built by the integration of grid power supply, line frequency transformer, power electronic switches, alternating current-direct current bridge converter, regulator, and resistor-inductor-capacitor. The excess-voltage protection and battery monitoring were obtained by the bi-controlled technique. In contrast to other charging systems in underdeveloped nations, the proposed system is very simple, rugged, reliable and cheap to maintain due to simplicity and un-programmed nature of the system. The results showed that the proposed system is craggy and robust to resist voltage stress, highly reliable and relatively free from leakage currents due to the presence of a double controlled scheme using a common point of action and a line frequency transformer. In addition, the system can be used to charge batteries ranging from 50μA and above. The system can be utilized in communication companies, electric vehicles, drilling machines

The influence of various chemical oxygen demands on microbial fuel cells performance using leachate as a substrate

Microbial fuel cells (MFCs), hailed as a promising technology, hold the potential to combat various wastewater pollutants while simultaneously converting their chemical energy into electricity through biocatalysts. This study explores the applicability of a dual compartment MFC (DC-MFC) under varying conditions, targeting the removal of chemical oxygen demand (COD) from landfill leachate and electricity generation. In this setup, anaerobic sludge from a wastewater treatment plant serves as the inoculum in the anode compartment of the MFC, with a Nafion117 membrane acting as the separator between MFC units. The cathode compartments are filled with distilled water and continually aerated for 24 h to enhance air supply. The study assesses the MFC's performance across different COD concentrations, focusing on COD removal, power generation, and Coulombic efficiency. The findings reveal that COD removal efficiency is notably enhanced at higher concentrations of organic matter. Specifically, at a COD concentration of 3325.0 mg L , the MFC exhibited the highest COD removal efficiency (89%) and maximum power density (339.41 mWm ), accompanied by a Coulombic efficiency of 25.5%. However, as the initial substrate concentration increased to 3825 mg L , the efficiency decreased to 72%, with a Coulombic efficiency of 13.56% and a power density of 262.34 mWm . Optical density levels increased due to bacterial growth at ambient temperature and neutral pH, reflecting the dynamic microbial response within the system. [Abstract copyright: © 2024. Crown.

Risk in housing development investment appraisal in Abuja, Nigeria

The growing prospect of any investor is to achieve maximum satisfaction in his investment. To attain the investment objective of maximizing wealth, maximizing returns and minimizing risks as a prudent investor will be paramount, therefore, chooses between ranks of alternative investments. Therefore, this study aims to identify various risk factors that affect housing investment appraisal and measure the level of familiarity with the risk factors in housing development investment appraisal in Nigeria. This study adopted the use of exploratory sequential methods which consist of expert opinion and survey method by using stratified sampling technique in administering questionnaires to the 160 estate surveyors and valuers in Abuja, Nigeria. The ordinal test was analyzed using frequency distribution while the nominal was analyzed using partial least square (PLS) analysis. The study, however, shows that estate surveyors and valuers are most familiar with four risk factors which include the economic factors, political factors, technological factors, and social factors. Therefore, there is the need for estate surveyors and valuers to increase their effort to ensure that risk factors that are prone to variation during appraisal estimates are managed, as it affects the outcome of housing development investment

Design and Implementation of a Transistorized Bi-Controlled based Utility-Connected Battery Charger for Underdeveloped Nations

This paper presents a transistorized bi-controlled based utility-connected battery charger to address the problem of erratic public power supply in underdeveloped nations. In this study, a utility battery charger was built by the integration of grid power supply, line frequency transformer, power electronic switches, alternating current-direct current bridge converter, regulator, and resistor-inductor-capacitor. The excess-voltage protection and battery monitoring were obtained by the bi-controlled technique. In contrast to other charging systems in underdeveloped nations, the proposed system is very simple, rugged, reliable and cheap to maintain due to simplicity and un-programmed nature of the system. The results showed that the proposed system is craggy and robust to resist voltage stress, highly reliable and relatively free from leakage currents due to the presence of a double controlled scheme using a common point of action and a line frequency transformer. In addition, the system can be used to charge batteries ranging from 50µA and above. The system can be utilized in communication companies, electric vehicles, drilling machines. &nbsp

Shunt compensation and optimization of Nigerian 330Kv 34 bus power system using metaphorless Rao-Type algorithms

Power system networks suffer from power losses and bus voltage violations due to heavy loading at the various buses. As a consequence, there is a need for some sort of compensation at the heavily loaded bus points. In this paper, a novel type of optimizer with fast convergence and simplicity called Rao-1, which is based on metaphorless programming, is presented for the task of optimization with shunt compensation on Nigerian 330-kV power network. The application of this algorithm for optimal shunt compensation of the Nigerian 330kV, 34-bus power transmission network is presented. The results obtained by Rao-1 technique are compared with particle swarm optimization (PSO). The findings show that using shunt compensation generally improves the precision of objective function values even though at some trials there might be deviations. Comparative results also show the competitiveness and efficacy of proposed Rao-1 type algorithm in terms of fitness scores and computational run time