The introduction of a decentralized energy system in remote rural areas with limited or no access to power supply can improve the quality of life of people living in these areas. Renewable energy technology can play a key role in electricity generation, as grid expansion is not a cost-effective option. In this study, we focused on the techno-economic feasibility and optimal design of a hybrid micro-hydro-photovoltaic-diesel-battery-wind power system designed to electrify a typical remote village located in the southern part of Nigeria. We aimed at achieving the electrification at minimal cost while taking into cognizance the constraints of environmental pollutant emission. In this study, the technical details, as well as the economic feasibility of setting up such a power system, were determined using the hybrid optimization of multiple energy resources (HOMER) simulation tool. Different combinations of energy resources including solar, wind, hydro, and diesel were compared and analyzed. The system performance and economics using some determinant factors such as the cost of energy, operation, and maintenance cost, net present cost, excess electricity, capacity shortage, generator fuel consumption rates, and cost, load fulfillment, and CO2 and other pollutant gas emission savings were determined. The experimental results and the comparative analysis revealed that a hybrid hydro/PV/wind/diesel/battery system was the most ideal and preferred option for off-grid rural electrification. The simulation results also indicated that the optimal system had a net present cost (NPC) and cost of energy (COE) of $1.01 m and $0.106/kWh, respectively, with a renewable fraction of 77.4% and environmental pollutant emission of 228,945 kg/year. This system was found to be environmentally friendly as it emitted the least pollutant gas among all the considered configurations. Bearing in mind the recent advocacy towards the actualization of Sustainable Development Goal (SDG) number 7, this work was found to be in alignment with the tenet of "Affordable and Clean Energy." INDEX TERMS Renewable energy, hybrid power system, net present cost, off-grid, techno-economic optimization, HOMER analysis tool.

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This paper studies in detail a systematic approach to offering a combination of conventional and renewable energy that is adaptable enough to operate in grid-connected and off- grid modes to provide power to a remote village located in Nigeria. To this aim, the HOMER pro software tool was used to model two scenarios from the on-and off-grid systems, evaluating in detail the techno-economic effects and operational behavior of the systems and their adverse impacts on the environment. The impacts of varying load demand, grid power and sellback prices, diesel prices, and solar irradiation levels on system performance were discussed. Results showed that, for both cases, the optimum design consists of a diesel generator rated at 12 kW, with a photovoltaic (PV) panel of 54 kW, a 70 battery group (484 kWh nominal capacity battery bank), and a 21 kW converter. The cost of electricity (COE) and net present cost (NPC) were in the range of $0.1/kWh to 0.218 $/kWh and $117,598 to $273,185, respectively, and CO2 emissions ranged between 5963 and 49,393 kg/year in the two configurations. The results of this work provide a general framework for setting up a flexible and reliable system architecture to ensure continuous power supply to consumers under all conditions.

Although corona discharge is notorious for its detrimental effects, it is also used in many beneficial practical applications. Despite the existence of a variety of sophisticated theoretical and experimental methods for investigating corona discharge, we explore yet a much simpler method that relies on the use of Dimensional Analysis (DA). The DA method does not demand profound knowledge of the underlying phenomenon or its governing equations, as it only needs the correct identification of the variables influencing the phenomenon, and the specification of their physical dimensions. The classical and well-known Gauss-Jordan elimination method is compared with other matrix-oriented computational approaches in analyzing the pertinent dimensional system. This method relies upon solution-preserving elementary row operations, i.e., operations that one can use on a matrix without spoiling the solution set for an associated matrix equation. A distinct advantage of this method is that it does not pre-suppose a particular value of the matrix rank but tackles the task of determining this rank while proceeding towards its ultimate result. Moreover, this method can also be used to find the inverse of a regular (invertible) matrix or to determine the solution (if any) of a system of linear equations. As a bonus, novel results of numerical investigations of bases, regimes, and dimensionless products are extensively presented in this paper. A remarkable observation made herein is that the set of variables pertinent for a particular phenomenon cannot be arbitrarily partitioned into basis (input) variables and regime (output or isolated) variables. The paper running example deals with expressing a specific variable, viz. ozone generation rate per unit length of wire (r0) through dimensionless products in terms of a set of determining or influencing variables.

Recently, off-grid renewable power generation systems have become good alternatives for providing reliable electricity at a low cost in remote areas. According to the International Renewable Energy Agency, more than half the population of Nigerian rural communities are outside the electricity coverage area. This research examines the potential application of hybrid solar photovoltaic (PV)/hydro/diesel/battery systems to provide off-grid electrification to a typical Nigerian rural village. The performance of four different hybrid systems was evaluated via techno-economic and environmental analysis, and the optimized solution was selected using the HOMER analysis tool. The simulation results revealed that a hybrid PV solar/hydro/diesel with battery storage was the optimized solution and most suitable with the least net present cost (NPC) of $963,431 and a cost of energy (COE) of $0.112/kWh. The results also revealed that the optimal system prevented about 77.1% of CO2 gas emission from being released to the surrounding air as compared with the PV/diesel system (worst case). In addition, the results also showed better performance in technical aspects, making the system appropriate and ideal for rural electrification and clean energy development. Furthermore, the effects of varying some variables such as interest rate, solar radiation, water discharge, capacity shortage, and battery minimum state of charge on the system cost and operational performance were discussed via the sensitivity analysis because these parameters influence the economy and technical aspect of the power system.