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Nigeria is purely an agrarian nation and the people depend on agriculture for survival. One of the missing links to wealth creation in Nigeria is lack of economic exploitation of abundant agricultural wastes. Instead of wealth creation, rice husk has become a serious threat to the environment. The unutilized rice husks in rice mills in Nigeria generate millions of tons of C02 when burnt. This increases environmental degradation and deaths associated with respiratory diseases. The sustainable use of this rice husk for bioenergy applications such as electricity generation at low cost, to mitigate greenhouse gas emissions is imperative. In this paper, an off-grid gasification power supply option for Adani, in Uzo-Uwani Local Government Area of Enugu state, of eastern Nigeria is presented. A detailed load assessment and availability of rice husk for power generation in the study area was conducted. This information was used to design the gasification system. The gasification system was designed based on the mass flow rate of producer gas required to power the gas engine at full load. The gasifier was designed downdraft with air and steam as the oxidizing agent, in order to maintain uniform temperature in the oxidation and reduction zones. Furthermore, techno-economic analysis approach was used to determine the economic viability of the designed power system considered in this study. The estimated total load demand of the study area is 850.054 k W . The estimated total daily, monthly and yearly energy demands of the study area are: 8,991 ​kWh, 269,736.42 ​kWh and 3,236,837.04 ​kWh. The annual availability of rice husk in the study area is 3,636 t / y and it has potential of 1.52 M W power generation with daily, monthly and yearly energy generation of: 36.48 ​MWh, 1,094.4 ​MWh and 13,132.8 ​MWh. This potential of electricity generation has power station capacity of 1.9 MVA, which is approximately equal to 2 MVA. The Levelized Cost of Electricity of the designed power system is 3.6 Naira/kWh, which is cheaper than 30.93 Naira/kWh tariff bill by Enugu Electricity Distribution Company to its R2S customers. Based on the proposed rice husk gasification system, a community could generate power to meet their electricity demand in most economical way, thereby reducing emission, waste and saving cost translating to sustainable development.

With the ever-increasing complexity of disturbed Power Systems, the method of protection using electromagnetic relays may not be adequate to afford appropriate discrimination especially when the fault current flows in parallel paths. Because the electromagnetic relay has slow response time, and the fact that it is a mechanical device and has moving parts, over a period of time, these moving parts will wear out and the relay will fail. To overcome these drawbacks, a more reliable means of system protection was carried out using solid-state contactless devices. A modular technique using five blocks made up of power supply unit, current sensor unit, voltage sensor unit, switching unit and output unit were used in the study design. A 66 kV power network was used to test the reliability of the protection designed circuit. Result shows enhanced system security.

The inability of power system to maintain a proper balance of reactive power is the major cause of voltage collapse. A system can be saved from voltage collapse by reducing the reactive power load or by adding additional reactive power into the system. The electric power system is afflicted with continuous load shedding due to inadequate generation and transmission capacities. To maximize the amount of real power that can be transferred over a network, reactive power flow must be minimized. Thus, sufficient reactive power should be provided locally in the system to keep bus voltages within stipulated ranges to satisfy customers’ equipment ratings. This paper presents an overview in reactive power compensation skills which remains as research challenges in this area. Newton-Raphson’s solution method was used to carry out the analysis because of its fast convergence, sparsity, and simplicity attributes when compared to other solution methods, with relevant data obtained from Power Holding Company of Nigeria (PHCN). MATLAB/SIMULINK was used to carry out the simulation analysis. It is observed that the application of compensation on the unified system jointly has effect on the other buses. This is confirmed by a step-by-step application of compensation at 5% intervals. The effects were noticed in Bus (20) where voltage decreased from 0.9568 to 0.9329 p.u. about 2.39%, bus (19) from 0.998 to 1.1035 p.u. and others. These results indicate undershoot and overshoot that will cause damage to the system, and may lead to system collapse if no contingency control is installed. It is also observed that compensation should be done on weak buses only for better results. The results indicate the enhancement in voltage profile in addition to reduction in the network losses and more balanced system. Active and reactive power control greatly influence the electricity grid, thus, need adequate attention with the recent advent of integration of renewable energy into the grid.