FEASIBILITY OF GRID-CONNECTED SOLAR PV ENERGY SYSTEM: A CASE STUDY IN NIGERIA

MUYIWA S. ADARAMOLA

5.1 INTRODUCTION

Availability and utilization of energy is essential for social and economic development of a society and it is an essential resource required to improve human standard of living and quality of life. In Nigeria, access to reliable and stable supply of electricity is a major challenge for both the urban and rural dwellers. However, this problem is more significant in the rural areas and communities where only about 10% of the population have to access to electricity [1]. Even in the urban areas where grid-connected electricity is available, access to electricity is still a big challenge due to low and in­adequate generation and distribution capacity. At the time of preparing this article, the peak electricity generation capacity in Nigeria is 3119.4 MW;

Reprinted from International Journal of Electrical Power & Energy Systems, Volume 61, Adaramola MS, Viability of Grid-Connected Solar PV Energy System in Jos, Nigeria, pp. 64—69, Copyright 2014, with permission from Elsevier.

which is about 24.4% of the peak electricity demand forecast of 12,800 MW for the same period [2]. This situation can be improved upon by us­ing renewable energy resources, especially solar energy, to supplement the grid electricity supply in Nigeria. However, due to intermittent nature of these resources, they may not be suitable and reliable as stand-alone en­ergy systems. Therefore, integration of both renewable energy conversion systems with storage facility could be a reliable energy system option in many locations in Nigeria.

In remote areas with no grid access, battery bank can be used as the storage facility. The negative effect of this is that additional cost of battery could significantly increase the unit cost of the electricity produced [3]. But, in areas with grid system, energy storage facility can be removed, and instead, the grid system can be used as ‘storage’ system. In this ar­rangement, when the renewable energy conversion system (RECS) pro­duce more energy than needed, the surplus energy is fed into the grid and, energy is taken from the grid when the RECS system produces less energy than needed. As outlined by Mondal and Islam [4], some of the other ad­vantages of PV-grid tied energy system includes: it can reduce energy and capacity losses in the utility distribution network, and it also can avoid or delay upgrades to the transmission and distribution network where the average daily output of the PV system corresponds with the utility’s peak demand period. This arrangement is a good option for a PV-grid energy system in a tropical region like Nigeria, due to high availability of solar radiation in the country (see Section 2 below).

Feasibility, reliability and economic analyses conducted in a number of studies showed that hybrid power systems either as standalone or grid – tied system, are more reliable and cheaper than single source energy sys­tems [see e. g., [5] and [6] and could produces less greenhouse gases when compare with fossil-fuel resources based energy systems [see e. g., [5], [6] and [7]. The objective of this work is to investigate the techno-economic viability of solar PV-grid connected energy system in a location north-east Nigeria. This energy system may not only improve access to reliable sup­ply of electricity, but can also reduce dependency on diesel generator sys­tems (which are commonly used to supplement grid supplied electricity in semi-urban and urban areas across the country), and thereby reducing the associated noise pollution and emissions from these diesel generators.

The energy system software, HOMER (Hybrid Optimization Model for Electric Renewable) is used to model the energy system and access its technical and economic performance.