Renewable Energy Mini-Grids As The Least Cost Energy Solution For The Electrification Of Off-Grid Areas: A Case Study On Born Island Electrification In Nigeria

ABSTRACT 

There is a growing interest in the application of microgrids around the world because   of their potential for achieving a flexible, reliable, efficient and smart electrical grid system and supplying energy to off-grid communities, including their economic benefits. Several research studies have examined the application issues of microgrids. However, a lack of in-depth considerations for the enabling planning conditions has been identified as a major reason why microgrids fail in several off-grid communities. This development requires research efforts that consider better strategies and framework for sustainable microgrids in remote communities.

This paper describes a microgrid for electrification of island. Photovoltaic, wind diesel generator and various storage systems were modeled to find the optimal design. The economic and environmental impacts are also studied.

TABLE OF CONTENTS

 TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF THE PROJECT
• PROBLEM STATEMENT
• JUSTIFICATION OF THE STUDY
• AIM/OBJECTIVE OF THE PROJECT
• DISSERTATION ORGANIZATION

CHAPTER TWO

LITERATURE REVIEW

2.0      LITERATURE REVIEW

2.1      THE RELEVANCE OF HYBRID SYSTEMS IN OFF-GRID ELECTRIFICATION PROJECTS

2.2      ALTERNATIVE METHODOLOGIES FOR OFF GRID ELECTRIFICATION PROJECTS

2.3      SYSTEMS OPTIMIZATION

2.4       WHY A HYBRID MINI-GRID

2.5      DIFFERENCES BETWEEN HYBRID POWER SYSTEMS, DIESEL GENSET POWER SYSTEMS, AND RENEWABLE ENERGY POWER SYSTEMS

2.6     DESIGN OF HYBRID MINI-GRIDS

2.7     REVIEW OF SIMILAR WORKS

CHAPTER THREE

3.0      METHODOLOGY

3.1      SOFTWARE MODEL

3.2      MICROGRID MODEL

CHAPTER FOUR

4.0       RESULT ANALYSIS

4.1      RESULTS

CHAPTER FIVE

• CONCLUSIONS

5.3     REFERENCES

CHAPTERONE

INTRODUCTION

1.1. Background of Study

Reliable and affordable energy is recognized as an essential ingredient for socio-economic development and economic growth of any country to meet the basic human needs such as cooking, lighting and safe drinking water as well as to improve, among others, education, communication and productive activities.

In order to move towards a sustainable existence in our critically energy dependent society, there is a continuing need to adopt environmentally sustainable methods for energy production. In Nigeria, as in most developing nations, the demand for sustainable energy is increasing due to population and developmental growth (Otun et al, 2012). Researches in this field have developed several methods of generating clean and affordable energy. Even though the use of fossil fuels for generation of electrical energy is more than the use of renewable sources, decreasing oil reserves in the world makes the potential for fossil fuels as a future resource of energy to be decreasing (Zehra and Muhsin, 2013). This leads to a significant interest in renewable energy sources therefore, making transition from fossil fuels towards renewable energy unavoidable (Zehra and Muhsin, 2013). The dependency on safe energy production system from renewable energy is increasing and gaining ground with the support from government policy around the world, especially with the instability of oil in the Middle East and the recent Fukushima nuclear disaster (Jungjohann and Rickerson, 2011). Renewable energy technologies offer the promise of clean, abundant energy gathered from self-renewing resources such as the sun, wind, water, earth and plants (Dorin et al, 2009). In most cases, one renewable energy system cannot fulfill the power requirement alone as it is intermittent in nature hence the solution is to hybridized the renewable energy systems (Meshram et al, 2013). To satisfy the power requirement, integration of the power grid is required. For supplying electric power in areas using this hybrid system, the power grid may be integrated. For the development of a system that will augment deficit of power, load forecasting is necessary.

According to the IEA (International Energy Agency) WEO (World Energy Outlook) 2017 estimates, almost 1.1 billion people—14% of the global population—do not have access to electricity, and more than 95% of them are in sub-Saharan Africa and developing Asia. Nigeria, despite making efforts to enhance electrification, only managed to reach an electrification rate of 47% in 2016. Looking at the current energy situation, there are still many challenges and weaknesses that affect the energy supply sector in Nigeria. The main ones are:

• low access to modern energy, especially for cooking, leading to high pressure on biomass resources;
• high cost of energy;
• energy demand increasing faster than the additional generation installation rate;
• high cost of rural electrification through grid extension due to the scattered nature of settlements; (v) frequent power outages and high system losses; and
• high dependence on imported petroleum fuels (Kiplagat and Wang, 2011). The Nigeria Government has developed the Nigeria Vision 2030 as the country’s new development blueprint.

The vision aims at transforming Nigeria into a newly industrializing, middle-income country providing a high quality of life to all its citizens by the year 2030, and has identified provision of energy as the key to meet its goals. Aligned to this strategy document, Nigeria has implemented the Energy Policy 2004, targeting to reach 40% electricity connectivity of the rural population by 2020, and has subscribed the UN Sustainable Energy for All Initiative and the manifesto of Jubilee Coalition (Nigeriatta, Ruto, Ngilu, Balala, Harmonised, 2013). To pursue energy access for all, the efforts are focused both on energy transmission and distribution, and power generation. Since the energy transmission is capital intensive and has hitherto concentrated in high population density and high economic areas, the Nigeria Government has installed off-grid diesel-based power stations and distribution mini-grids covering some remote rural areas for which the connection to the national transmission grid is not feasible. The systems based on diesel generation installed by the Ministry of Energy and Petroleum to supply electricity to areas which are far from the national grid have experienced several challenges, such as:

• the cost of fuel increases with the remoteness of the location due to logistic costs;
• on-site storage challenges;
• high operation and maintenance costs; and (iv) the gas emissions contribution to environmental pollution and global warming (CO2).

In 2010, the Ministry of Energy and Petroleum, through the Nigeria Power Company, commenced a pilot program to hybridize these off-grid power stations by installing renewable energy power sources, particularly wind and PV-solar. Currently, there are off-grid diesel power stations as well as pilot hybrid systems (solar, wind or solar/wind), and new installations by the Rural Electrification Authority (REA) are currently ongoing. One of such operational stations is, which consists o f a 410 kW diesel generator, a 60 kW wind power plant and a 30 kWp photovoltaic (PV) solar plant.

1.2. Statement of the Problem

The installations of off-grid hybrid systems in remote areas, promoted by the Ministry of Energy and Petroleum, were done without a proper study and optimization. No detailed analysis has been done to establish the performance, reliability and sustainability of the hybrid power stations in the Nigerian context. The power station is one of the pilot off-grid hybrid stations, but the contribution of renewable energy is very low, since the energy is generated almost exclusively by the diesel generator. This study is thus geared towards covering this existing gap in relation to hybrid off grid power stations in Nigeria, assess their sustainability and feasibility in meeting the rural electrification challenges, including optimization criteria and levels. Furthermore, it is prudent to investigate ways of ensuring grid stability from these variable renewable energy sources.

A number of research works had been conducted to augment the deficit of power in the grid which is due to increasing demand of energy and insufficient generation. Power from the grid was not sufficient due to network expansion, urbanization, migration and greater demand of power by the consumers and no plan for increase in generation by the utility was made. This results in load shading by the utility in order to balance the generation with the load. This decreases the power quality and security of the utility grid and brought the need for alternative means of power generation to support the utility grid. In this work, load profiling was done using artificial neural network based on Bayesian regularization algorithm. The model was developed putting in cognizance the effect of environmental condition which includes temperature, relative humidity, rainfall, wind speed, solar radiation and sunshine hours.

1.3. Justification of the Study

As the Ministry of Energy and Petroleum promotes the installation of hybrid stations in remote areas, it is fundamental to conduct an in depth technical assessment of the existing hybrid plants on their system reliability, the value for the investments and their current system performance to advise their optimization by using renewable energy resources and ensure the technical and financial sustainability. The outcome of this study will reinforce the policy making activities of implementing the hybridization program. Furthermore, this study aims at providing information about the use of mini-grids as a convenient solution to increase electricity access in remote areas. This information is required to provide impetus to upscale the installation of the mini-grids and hybrid systems. The study will also provide technical inputs on methods and ways of optimizing the hybrid-systems.

1.4. Objectives of the study

The overall objective of this research is to reinforce the policy making activities of implementing the hybridization of off-grid power stations program in Nigeria and provide lessons learned on the development of mini-grids aimed at increasing access to electricity in remote areas of developing countries.

The specific objective of the research is to evaluate the performance of the off-grid hybrid power station based on wind, PV-solar and diesel generation, assess the potential of the renewable energy sources and optimize the existing systems to enhance its reliability, performance and sustainability.

1.5 Dissertation Organization

In chapter one, general background and the concept of Renewable Energy Mini-Grids is presented, followed by the least cost energy solution for the electrification of off-grid areas. In chapter two, a concise review of the fundamental concepts and literature review on Renewable Energy Mini-Grids are presented. In chapter three, methods and materials are presented which comprise the mathematical models and Simulink models of the Renewable Energy Mini-Grids. In chapter four, result was presented based on the analysis of the load profiling and solar-hydro hybrid model. Chapter five presents the conclusion, recommendation and limitations of the entire research work.