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Nigeria has a large deposit of clay which is the major raw material for the fabrication of porcelain insulators for high voltage applications. However, the country depends largely on imported porcelain insulators to meet its high voltage needs even in the face of the worsening exchange rate of the Nigerian currency compared to the US dollar and other foreign currencies. As a result, it becomes necessary to sort for local means of fabricating high voltage pin insulators from locally available raw materials. In this study, clay sourced from three different geographical locations (Auchi, Ikorodu, and Ota) are used to fabricate three samples of high voltage insulators. The fourth sample of insulator is also fabricated from the Ota clay with Plaster of Paris (POP) as an additive to enhance workability. The physical and electrical properties of the insulator samples are investigated and compared with imported porcelain insulators. The results show that the insulator fabricated using the clay from Auchi has the highest breakdown voltage of 5 kV and lowest leakage current of 2 mA and thus can be adopted for low-tension insulation instead of the high-tension insulation speculated from the onset of the research.

The burning of fossil fuel for power generation emits Greenhouse gases into the environment. Greenhouse Gases (GHGs) emission is the principal cause of global warming. In order to regulate the emissions of these gases, the emissions need to be assessed and quantified. Carbon footprint is the evaluation of human activities that lead to GHGs emissions. The Covenant University Electricity Network during periods when utility supply fail runs on diesel powered generators located at different centers within the campus. These generators emit carbon-based compounds into the environment. Assessing the quantity of carbon dioxide which is the principal GHGs emitted per year gives 33.14-tonnes. Analysis of the load profiles in the centers showed that all the eight generators are not supposed to be running simultaneously as it is now. This study developed a new network model where all the generators were integrated into a DC microgrid that ensured resource sharing. The model was simulated using energy management and optimization techniques resulting in reduced micro-generators engagement, Green House Gases emission and fuel consumption. Consequently, carbon dioxide emitted per year dropped to 18.44-tonnes from 33.14-tonnes. The developed model improved the carbon footprint of the campus by as much as 44.3%.

In a developing nation like Nigeria, the conventional load monitoring and billing system has proved to be tedious, time-consuming, expensive, and prone to human error over the years. Therefore, this creates the need for an efficient system that can assist the Utility to monitor the energy consumption trend of the customers remotely. This work developed a web-based single-phase load monitoring and auditing system using NodeMCU (ESP8266) microcontroller, PZEM-004T sensor, and liquid crystal display (LCD) module for the hardware unit and Blynk internet of things (IoT) platform for the software unit. The system design was implemented around the ESP8266 microcontroller with relevant design models, and standard power and energy equations programmed into the microcontroller in the Arduino integrated development environment. The developed system was load tested to examine its performance and determine its reading error. The hardware and software units of the system operated satisfactorily when tested. The reading accuracy for current and voltage measured by the device were ±0.2% and ±0.4%, respectively, giving a reading error of ±0.8% for power measurement. The developed system is suitable for residential, commercial, and similar applications where the energy usage trend of some small loads is required for management purposes.

Frequent burning of three-phase induction motors windings has been reported. The initial symptoms observed before the burning of the windings were an increase in operating current and a temperature rise. The induction motor protection and control system was designed, developed, and constructed to reduce the problem of burnt winding by early detection and disconnection of supply if the problem persists. It was found to be efficient, reliable, durable, and rugged. The system is a boost to Nigerian industrialists as it will reduce cases of burning of induction motors and the consequent downtime and cost. The system is cheap and easy to repair and maintain because the parts and components used in the design are available locally.

Cooking from ancient times has evolved from using open fires to wood, gas cookers, using liquefied petroleum gas (LPG). This has also come with various adverse effects ranging from gas leakages to burnt food due to absent-mindedness, thereby creating a significant disaster that could lead to loss of life and property damage. The study aimed to reduce the rate of liquefied petroleum gas related accidents in domestic usage and improve the safety of domestic gas users. An automated method to enforce safety was proposed to avoid unwanted cooking gas flow consequences, especially in homes. The paper presents a control system using an Arduino Uno with a control design interfaced with a utensil sensor, solenoid valve, and a timer circuit to allow gas flow to commence and ignite a flame automatically. The automatic ignition apparatus, which has a high-voltage electric circuit, begins to function once the utensil detector comes in contact with silverware. The system is designed to function in different modes to ensure safety and prevent gas flow. The prototype serves as a means of curbing gas wastage and increasing the safety of people who use LPG as a source of fuel for cooking.

Over the years, there has been increasing interest in exploitation of renewable energy source (RES) as a result of fast depletion of fossil fuel based conventional power generation with attendant negative environmental impact. However, renewable energy sources such as solar, wind, biomass etc are not always available because of their fluctuating nature. In view of this, it has become imperative to have an efficient energy storage system (ESS) for sustained energy availability. Batteries storage often suffers early failure due to irregular charge and discharge cycle which could eventually shorten its life span. Therefore, this research focuses on investigation of the influence of meteorological parameters on battery storage in solar PV system as well as evaluating the influence of these factors on the performance characteristics of solar PV storage system. The work examines particularly the effect of varying solar temperature and irradiance on the system output charging current and overall efficiency. A modified mathematical model of a solar PV was developed to show the relationship between meteorological parameters (irradiance and temperature), and PV output short circuit current. Analysis of meteorological data obtained for determination of state of charge (SOC) of battery storage based on the six geographical areas in Nigeria revealed that, in Bornu state (North-east) the battery attained 100% (hundred percent) state of charge in1Hr (one hour), while in Plateau state (north-central), the battery attained 60% (sixty percent) state of charge in 8hrs (eight hours), being the least in terms of charging rate. In Kaduna (North-west) region, the battery attained 88% state of charge in one hour and 96% SOC after duration of eight hours. This is quite different from Lagos (Southwest), where the battery SOC in one hour was 38% and 78% SOC in eight hours. This phenomenon therefore, revealed that solar PV system implementation should be site specific and it also account for the life span of the storage and the system efficiency.

With the high rate of economic development, there is an increasing load demand even in rural communities and Obayantor in Nigeria. Obayantor, having zero connection to the primary grid, needs electricity. Following the community located in a tropical rejoin of Nigeria, it has enough solar energy sources.  With the high price of diesel fuel, solar microgrid seems to be the best energy solution for the rural community.    In this study, technical and economic analysis was carried out on the solar-based microgrid and compared with a diesel-only microgrid using MATLAB Software tool. The results show that the solar microgrid is more cost-effective and has a cheaper COE, affordable for the rural community compared with the diesel microgrid, which is more expensive to afford.  The Annual system cost for the solar microgrid was lower compared with the diesel source. The result also revealed that the diesel-alone microgrid system is 4.71 times and 0.2 times more costly than the solar-based microgrid system in terms of the cost of energy and ASC, respectively. Thereby making the diesel microgrid not having technical and economic feasibility for the community.

In this study, the real-world performance analysis of four Nigerian mobile network operators (MNOs), namely MTN, GLO, Airtel, and 9Mobile long-term evolution (LTE) cellular network, were analyzed and compared. The Nigerian MNOs utilize 5 MHz, 10 MH, and 20 MHz channel bandwidths based on third-generation partnership project’s (3 GPPs) recommendation. The presented analysis shows the uplink (UL), and downlink (DL) throughputs gaps in mobility condition as well as other LTE’s system quality of service (QoS) key performance indicators (KPI’s) of: Connection drop rate, connection failure rate, peak physical downlink throughput, minimum radio link control (RLC) downlink throughput threshold and latency are not strictly followed. The reason may be due to a lack of regulatory oversight enforcement. The comparative studies showed that MTN provides the best QoS. The introduction of novel LTE QoS metrics herein referred to as national independent wireless broadband quality reporting (NIWBQR) is the significant contribution of this study. The goal of this study is to show the quality of the network as it affects the user's experience. Important observation showed that all the MNOs are not adhering to the 3 GPPs specified user plane latency of 30 ms and control plane latency of 100 ms, respectively, which makes video streaming and low latency communication a near-impossible task.

The deregulation of the Nigerian power sector has resulted in the quest to explore power generation options for power quality improvement. One of such options is the pattern shift from central power generation to embedded power generation. Network integration of embedded generators (EGs) causes several regulatory, technical and economic issues. This research focuses on power quality challenges that may arise as a result of network integration of embedded generation in a weak electricity networks using Ogba 33 kV injection substation as case study. The embedded generators considered comprised of gas turbine and diesel generators. NEPLAN software was used to perform the load flow analysis with and without EGs connection on the network. This was necessary so as to ascertain the healthiness of the existing distribution network for EGs integration. The power quality issues considered in the study were bus voltage profiles and the total line losses. Simulation results showed that EGs connection improved the voltage profile, for example, bus voltage at PTC 11 kV, improved from 0.881 pu to 0.958 pu while the total active power loss was reduced by 78.16%. The results obtained suggest that the grid is healthy enough to accommodate the EGs with no quality issues.

Cadmium-Zinc-Telluride (CZT) detectors are seen as an ideal material for constructing intrinsic detectors for neutrino-less double-beta decay. However, the poor mobility of the charge carriers (specifically the holes) is known to result in poor resolution and decreased photo-efficiency. Simulations of this effect show that the resolution is a function of the detector width/depth ratio, suggesting pixelation as a solution. Pixelation of the detector also allows background sources, and even single-beta events to be selectively vetoed. However, this technique alone cannot completely remove the effect of the reduced resolution. A technique which combines ‘Gain Matching’ and removal of the low energy tail is outlined and qualified for the resulting improvements in resolution and efficiency. The sharing of events between multiple pixels is also studied and the quality of reconstructed events is established. The pixelated nature of the detector also opens the door to operation of the detectors as a ‘Compton Camera’. Accordingly, Geant4 simulations are compared with real-world measurements, to establish the benefits of pixelation upon the operation of the detectors as a ‘Compton Camera’. Finally, comparisons are performed between Geant4 simulations and real-world measurements of intrinsic photopeak efficiency calculations.