O. O. Ajayi

The Potential for Wind Energy in Nigeria

This paper discusses some of the issues of wind energy development and utilization in Nigeria. It surveys the various initiatives of governments and researchers at assessing the prospects and availability of wind energy for electricity production and identifies indices suggesting wind availability. Inland, the wind is strongest in hilly regions of the North, while mountainous terrains of the middle belt and northern fringes have high potential for great wind energy harvest. However, due to varying topography and roughness of the country, large differences may exist within the same locality. Mean wind regimes in the north and south were also found to lie between 4.0 – 7.5 m/s and 3.0 – 3.5 m/s respectively at 10 m above the ground. It is suggested that Nigeria can adequately utilize wind for power generation over much of the country, if the identified challenges are overcome and the suggested strategies are implemented.

Nigeria's Energy Challenge and Power Development: The Way Forward

The ever increasing demand and meager supply of energy in Nigeria has been a great challenge to her development. This situation is becoming critical, with increasing population not balanced by an adequate energy development programme. The incessant power generation failure has grossly affected the economy, seriously slowing down development in rural and sub-rural settlements, with present energy policy mainly benefiting urban dwellers. Globally, energy projections stipulate that between 2002 and 2025, global energy needs may rise by over 34%, with that of developing nations doubling this percentage. A robust solution must be found to end the nations energy crises. This Viewpoint compares the energy potential of Nigeria with the challenges faced. Nigeria receives a huge amount of solar radiation, has abundant wind energy resources, and large deposits of fossil fuel, as well as enormous hydro-power resources from Niger and Benue Rivers. However, of these about 80% of hydro-power remains untapped, the total 5.5KW-hr/m 2 /day of solar radiation is not utilized and wind energy resources remain unexploited. The solution lies in creating a mixed supply of energy in which as yet untapped renewable resources are combined with abundant non-renewable fossil fuel, including the massive quantities of gas wasted from crude oil exploitation.

Wind profile characteristics and turbine performance analysis in Kano, north-western Nigeria

This study analyzed the electricity generation potential from wind at Kano, Nigeria (12.05°N; 08.2°E; altitude 472.5 m; air density 1.1705 kg/m3). Twenty one years (1987 to 2007) monthly mean wind speed data at a height of 10 m were assessed from the Nigeria Meteorological Department, Oshodi. The data were subjected to different statistical tests and also compared with the two-parameter Weibull probability density function. The outcome shows that the average monthly wind speed ranged from 6.6 to 9.5 m/s. Seasonally, average wind speeds ranged between 6.6 to 8.5 m/s and 7.4 to 9.5 m/s for dry (October to March) and wet (April to September) seasons, respectively. Also, estimated monthly wind power ranged between 3.6 and 12.5 MWh/m2. The most probable and maximum energy carrying wind speeds were also determined and the two parameters of the Weibull statistics were found to lie between 2.1 ≤ k ≤ 4.9 and 7.3 ≤ c ≤ 10.7, respectively. These results indicate that wind speeds at Kano may be economically viable for wind-to-electricity at and above the height of 10 m. In addition, five practical turbine models were assessed for the site’s wind profile, with results suggesting strong economic viability.

Degradation of Polynuclear Aromatic Hydrocarbons by Two Strains of Pseudomonas

The goal of this investigation was to isolate competent polynuclear aromatic hydrocarbons degraders that can utilize polynuclear aromatic hydrocarbons of former industrial sites at McDoel Switchyard in Bloomington, Indiana. Using conventional enrichment method based on soil slurry, we isolated, screened and purified two bacterial species strains PB1 and PB2. Applying the ribotyping technique using the 16S rRNA gene analysis, the strains were assigned to the genus Pseudomonas (Pseudomonas plecoglossicida strain PB1 and Pseudomonas sp. PB2). Both isolates showed promising metabolic capacity on pyrene sprayed MS agar plates during the preliminary investigations. Using time course studies in the liquid cultures at calculated concentrations 123, 64, 97 and 94 ppm for naphthalene, chrysene, fluroanthene and pyrene, P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 showed partial utilization of the polynuclear aromatic hydrocarbons. Naphthalene was degraded between 26% and 40%, chrysene 14% and 16%, fluroanthene 5% and 7%; pyrene 8% and 13% by P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 respectively. Based on their growth profile, we developed a model R2 = 1 to predict the degradation rate of slow polynuclear aromatic hydrocarbon-degraders where all the necessary parameters are constant. From this investigation, we confirm that the former industrial site soil microbial communities may be explored for the biorestoration of the industrial site.

Fuel Subsidy Reform and Environmental Quality in Nigeria

The study examines the existence of a long run effect of fuel subsidy reform on environmental quality in Nigeria for the period of 1970-2012 using the Johansen and the Engle–Granger two step co-integration procedure techniques. The study developed a three case scenarios including: (i) A case of subsidy payment, (ii) a case of effective subsidy and, (iii) a case of no subsidy payment. Findings from the study supported evidence of a long run sustainable equilibrium model. Also, our estimation results showed that the first and the last case scenario do not significantly influence environmental quality. This implies that subsidy payment in Nigeria does not enhance access and consumption of liquid fuel. On the other hand, the interaction of sound regulatory framework with subsidy payment (the case of effective subsidy) significantly exerts a responsive influence on environmental quality.

Finite Element Modelling of Electrokinetic Deposition of Zinc on Mild Steel with ZnO-Citrus sinensis as Nano-Additive

The electrokinetic deposition of zinc on mild steel substrate under the influence of ZnO-Citrus sinensis nano-additive was investigated numerically using a Finite Element (FE) solver. The conductivity of the Acid chloride plus ZnO-Citrus sinensis nano-additive electrolyte and the properties of Zinc and mild steel electrodes were used as the input codes for the model. The model was designed on a 3-dimensional scale. The boundary conditions were set and the model was meshed using the finer mesh capability in the FE solver. The model was processed and readings of the modelled zinc deposited mild steel were taken, validated and analysed so as to get the optimum parameters from the deposition process. Based on the results, the deposition mass and thickness increased with deposition time with ZnO-Citrus sinensis nano-additive, it is thus recommended that relatively high deposition time should be used in order to achieve optimum deposition.

Data on the no-load performance analysis of a tomato postharvest storage system

In this present investigation, an original and detailed empirical data on the transfer of heat in a tomato postharvest storage system was presented. No-load tests were performed for a period of 96 h. The heat distribution at different locations, namely the top, middle and bottom of the system was acquired, at a time interval of 30 min for the test period. The humidity inside the system was taken into consideration. Thus, No-load tests with or without introduction of humidity were carried out and data showing the effect of a rise in humidity level, on temperature distribution were acquired. The temperatures at the external mechanical cooling components were acquired and could be used for showing the performance analysis of the storage system.

Process variability analysis in make-to-order production systems

Abstract Vehicle license number plate production in Nigeria faces high variability in terms of process times and inter-arrival times, resulting in poor production schedule reliability. This study aims to clarify the level of such variation and to provide process improvement strategies within plate production. The specific objectives herein include identifying assignable variables, estimating variability indices and minimizing variation by developing solutions to improve system performance. This study explores the variability pooling method in assessing potential cost-effective process improvements and a case study is conducted on four Nigerian vehicle license number plate production plants in order to demonstrate the applicability of the proposed technique. Structured questionnaires were circulated to plant workers and data collected from plant production records from 2012 to 2015 in seven production lines were analyzed. A preliminary study on the production lines revealed the coefficient of variation (CV) for the Awka, Gwagwalada, Lagos and Lagos State Plants, showing measured variability levels of 0.62, 0.67, 0.60 and 0.78, respectively. Comparatively, the results obtained after the variability pooling showed a significant improvement in performance characteristics, such as low CV levels, enabling a 68% increase in net annual income for each plant, as well as enhanced machine utilization.

Investigation of Wear Land and Rate of Locally Made HSSCutting Tool

Production technology and machining are inseparable with cutting operation playing important roles. Investigation of wear land and rate of cutting tool developed locally (C=0.56%) with an HSS cutting tool (C=0.65%) as a control was carried out. Wear rate test was carried out using Rotopol –V and Impact tester. The samples (12) of locally made cutting tools and one (1) sample of a control HSS cutting tool were weighed to get the initial weight and grit was fixed at a point for the sample to revolve at a specific time of 10 mins interval. Approach of macro transfer particles that involved mechanism of abrasion and adhesion which was termed as mechanical wear to handle abrasion adhesion processes was used in developing equation for growth wear at flank. It was observed from the wear test that best minimum wear rate of 1.09 x10-8 and 2.053x10-8 for the tools developed and control were measured. MATLAB was used to simulate the wear land and rate under different conditions. Validated results of both the experimental and modeling showed that cutting speed has effect on wear rate while cutting time has predicted measure on wear land. Both experimental and modeling result showed best performances of tools developed over the control.

Impact of Heat Treatment on HSS Cutting Tool (ASTM A600) and Its Behaviour during Machining Of Mild Steel(ASTM A36)

Carburization is one the best heat treatment that responded well to hardening with Palm Kernel Shell giving the best hardness value. This work studied the influence of carburization on HSStool(ASTM A600) and its behaviour during machining of mild steel (ASTM A36). Composition of the samples (12 pieces of 180 x 12 x12 mm) HSS tools were checked using UV-VIS spectrometer and the tools were carburized with PKS at holding temperatures and time of 800, 850, 900,950 oC and 60,90 120 minutes using muffle furnance. The micro structural analysis, surface and core hardnessof the treated samples gave better results than the untreated samples when checked withsoft driven and optical microscope. It wasalso observed that increase in the feed rate and depth for length of cut of 50 mm significantly reduces the wear progression and thereby gave best machining time at maximum carburizing temperature and time(950 oC / 120 minutes) when it was used to cut mild steelon the lathe machine.