International Journal of Advance Foundation and Research in Science & Engineering (IJAFRSE)
Volume 1, Issue 5, October 2014. Impact Factor: 1.036, Science Central Value: 10.33
The Nigerian Power System Till Date: A Review.
Folorunso Oladipo1, Olowu Temitayo O2
Department Of Electrical/Electronic
Afe Babalola University, Ado-Ekiti1, Obafemi Awolowo Univeristy, Ile-Ife2, Nigeria
ABSTRACT
The fundamental ingredient for the growth of any country is how effective their power sector is.
Power system holds the key to the development of the world. Consequently, this paper looks into
how power system of Nigeria has contributed to the development of the nation. It takes a critical
survey of the past and present condition of the sector. The paper also looks into what were the
challenges of the sector, and possible solutions.
Index Terms : National Electric Power Authority (NEPA), Niger Dams Authority (NDA), Power
Holding Companies of Nigeria (PHCN), Independent Power Producers (IPPs), Transmission
Company of Nigeria (TCN), Power Station (P.S).
I.
INTRODUCTION
The present population of Nigeria is over 170 million, at a growth rate of 6% per annum. Nigeria is of no
doubt the biggest country in Africa continent with a total 356, 667 sq miles (923, 768 sq km), of which
351, 649 sq miles (910, 771 sq km or 98.6% of total area) is land. The nation is made of six Geo-Political
Zones subdivided into 36 states and the Federal Capital Territory (FCT). For a country of such bogus
population to thrive, its power sector must be strong. The major aim of this paper is to x-ray the
beginning and the present state of the Nigerian Power Sector (NPS). Therefore a history of the sector is
very vital and it cannot be over emphasized.
Electricity produce in Nigeria has it date back to 1896 when two (2) small generating sets were installed
to serve the then Colony of Lagos. The total capacity of the generator used then was 60kW. The maximum
demand was even lesser than the 60kW generated. It was fifteen years after England has been experience
power supply this occurrence happened in Nigeria [1].
In 1946, the Nigerian government electricity undertaking was established under the jurisdiction of Public
Works Department (PWD) to take over the responsibility of electricity supply in Lagos State [3].
By an Act of Parliament in 1951, the Electricity Corporation of Nigeria (ECN) was established, and in
1962, the Niger Dams Authority (NDA) was also established for the development of Hydro Electric
Power. However, a merger of the two (2) was made in 1972 to form the National Electric power
Authority (NEPA). Since ECN was mainly responsible for distribution and sales and NDA was created to
build and run generating stations and transmission lines, the primary reasons for the merging the
organizations were [2]-[1].
For over twenty years prior to 1999, the power sector did not witness substantial investment in infrastructural development. During that period, new plants were not constructed and the existing ones
were not properly maintained, bringing the power sector to a deplorable state. In 2001, generation went
down from the installed capacity of about 5,600MW to an average of about 1,750MW, as compared to a
load demand of 6,000MW. Also, only nineteen out of the seventy-nine installed generating units were in
operation [5].
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International Journal of Advance Foundation and Research in Science & Engineering (IJAFRSE)
Volume 1, Issue 5, October 2014. Impact Factor: 1.036, Science Central Value: 10.33
The National Electric Power Authority was a vertical-integrated utility responsible for the power sector
in Nigeria. And between 1970s and 1980s, NEPA developed new generating capacity in both hydro and
thermal power. NEPA was solely responsible for the generation, transmission and distribution of
electricity until year 2005 the unbundling and the power reform took place under the administration of
President Olusegun Obasanjo whereby the organization name was changed to Power Holding Company
of Nigerian (PHCN).
In March 2005, when President Olusegun Obasanjo signed the Power Sector Reform Bill into law, private
companies were given opportunities to participate in electricity generation, transmission and
distribution. The deregulation of PHCN was to consists eleven distribution companies (DISCOS), six
generating companies (GENCOS), and one transmission company (TRANSCOS) [4]. TRANSCO was to be
under the control of the Federal Government. It is to be noted that the establishment of PHCN was to
cater for the lack of inefficiency of NEPA, and to improve power system in Nigeria.
On August 8, 2005, the peak generation was 3774 MW out of the available generation of 4000MW. This
improvement was said to be as a result of the participation of the private investors and rehabilitation of
generating plants.
By 2010, however, five years into the latest reform, very little restructuring had been undertaken, and
available generation capacity was less than 4,000 MW (a figure largely unchanged since the 2005
reforms), for a population of over 150 million, the largest on the African continent [6].
Due to emergency power situation of the country, and the opportunity for private investors to participate
in the sector, the genealogy of Independent Power Producers (IPPs) started from these scenarios. The
first Nigeria’s IPP was established in 1999 by the Lagos State Government, the Federal Ministry of Power
& Steel and NEPA.
As of 2012, three large-scale IPPs produce approximately 25 percent of Nigeria’s electric power, with the
balance provided by the Power Holding Company of Nigeria (PHCN) and State governments, viz. about
1,000 MW (IPPs) and 3,000 MW (non-IPP), respectively.8 9 The introduction of IPPs has been gradual
(dating to 1999), but according to the ‘Road Map’, the private power component will more than double in
less than five years, including via the country’s sale of its generating assets [7b]. Given the significant
imminent change, a clear understanding of past experience with IPPs is paramount.
It was initially stated that the PHCN is unbundled into eighteen successor companies. Strategically, the
objectives of the reform include (i) the transfer of management and financing of successor companies
operations to the organized private sector; (ii) the establishment of an independent and effective
regulatory commission to oversee and monitor the industry; and (iii) focusing the FGN on policy
formulation and long-term development of the industry. This will lead to (i) increased access to
electricity services; (ii) improved efficiency, affordability, reliability and quality of services; and (iii)
greater investment into the sector to stimulate economic growth. However, the unbundling leaves the
Federal Government with three hydro and seven thermal generating stations with a total installed
capacity of about 6,852MW, with available capacity of 3,542MW (as of 31st July 2010).
Each entity had been incorporated as a single-asset generating company; a radial transmission grid
(330kv and 132kv), owned and managed by the Transmission Company of Nigeria (TCN), with the
responsibility of undertaking the system operation and market settlement functions, respectively as well
as eleven distribution companies (33kv and below) that undertake the wires, sales, billing, collection and
customer care functions within their area of geographical monopoly.
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A competitive tender was thereafter carried out to receive bids from core investor groups (inclusive of
competent generation asset owner/operators) for a minimum of 51% of equity in the following successor
thermal generating companies including
• Afam Power Plc;
• Sapele Power Plc;
• Ughelli Power Plc;
• Geregu Power Plc
As well as a separate concessioning process for successor hydro generating companies including
• Shiroro Hydro Power Plc;
• Kainji Hydro Power (note: that Jebba power station is part of Kainji Hydro Power Plc).
A similar competitive tender was carried out to receive bids from core investor groups (inclusive of
competent distribution asset owner/operators). They are
• Abuja Electricity Distribution Plc;
• Benin Electricity Distribution Plc;
• Eko Electricity Distribution Plc;
• Enugu Electricity Distribution Plc;
• Ibadan Electricity Distribution Plc;
• Ikeja Electricity Distribution Plc;
• Jos Electricity Distribution Plc;
• Kaduna Electricity Distribution Plc;
• Kano Electricity Distribution Plc;
• Port Harcourt Electricity Distribution Plc and
• Yola Electricity Distribution Plc.
As at September 2014,
• Available Generation Capacity is 6,662MW
• Generation Capacity is 5,228MW
• Peak Generation is 4,420MW
• Expected Generation from NIPP is 5,453MW and
• On-going Hydro Projects is 4,234MW
Power Industry projected to have available 10,000MW in 2015 and 20,000MW 2020 [8].
II. NIGERIA’S GENERATION COMPANIES
1) Afam Power Plc
Afam Power Station has an installed capacity of 776MW, The plant was commissioned in phases. During
the Initial phase, 1962-1963, gas turbine units 1- 4 were commissioned. During the second phase, 1976
to 1978, gas turbine units 5 to 12 were commissioned. Gas turbine units 13 to 18 were commissioned in
1982. Two gas turbine units were added in 2001 during the final phase of the Afam Power Station
extension.
2) Shiroro Hydro Power Plc (concession)
Shiroro Power Plant was commissioned in 1990; it has an installed capacity of 600 MW, It currently runs
at full capacity, generating 2, 100 GWh of electricity annually. As Nigeria’s newest hydroelectric plant,
Shiroro hosts Nigeria’s SCADA-operated national control centre. Shiroro is also equipped with switch
yard facilities that include a technical “step down” function for enhanced distribution into the national
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International Journal of Advance Foundation and Research in Science & Engineering (IJAFRSE)
Volume 1, Issue 5, October 2014. Impact Factor: 1.036, Science Central Value: 10.33
grid, an advanced control room and modern training facilities. The plant is situated in the Shiroro Gorge
on the Kaduna River, approximately 60 km from Minna, capital of Niger State, in close proximity to
.Abuja, Nigeria’s federal capital
3) Ughelli Power Plc
Ughelli Power Plc operates a gas-fired thermal plant located in the Niger Delta region. Ughelli Power is
one of the largest thermal generating power stations in Nigeria. The plant has a peak capacity of 972 MW;
it can generate 2500 GWh of electricity annually. The plant meets current world specifications for plants
of its type, and includes an updated control room, a switchgear room, a staff training school and
recreational facilities. Ughelli began operations in 1966.
4) Kainji/Jebba Hydro Electric Pic (Concession)
Kainji/Jebba Power operates as two hydro generation plants, each drawing water from the River Niger.
The combined installed capacity of the two plants is 1330 MW, with Kainji generating 760 MW and Jebba
570 MW Effectively, the plants operate at full capacity. Kainji began operation as Nigeria’s first hydro
power plant in 1968 while the Jebba plant was commissioned in 1985. Jebba is the smallest ofthe three
operating hydro Power plants in Nigeria. In addition to generation facilities, the hydro plants have on-site
Medical facilities a staff school, a recreation centre, and a training school. The two plants are in very good
condition.
5) Sapele Power Plant
Sapele Power Plant is a Thermal generating station located in Nigeria’s gas- rich Delta State. Sapele has
an installed capacity of 1020 MW Sapele Power’s six 120 MW steam turbines generate a daily average of
86.72 MWI.j/H or approximately 2,500GW/H annually Sapele. Power currently operates at a peak
capacity of 972 MW Sapele Power is strategically located in the Niger Delta region, close to sources of
both natural gas feedstock and a river for cooling its steam turbine generators Sapele Power Includes an
updated control room, a switchgear room, a Staff training school, and medical recreational facilities.
Sapele Power began operations in 1978.
6) Calabar Thermal Power Station
Calabar Power Station has an installed capacity of 6.6 MW derived from three units of 2.2 MW each.
Currently, it supplje 4.4 MW to the national grid and Primarily serves as a booster station to the Afam and
Oji River power stations The Calabar Power Station was built in 1934.
7) Oji River Power Station
Oji River Thermal Power Station was originally built to take advantage of plentiful nearby deposits of
high-gra5 coal. Oji generates io MW of power from five coal-fired boilers and four steam turbines
originally installed in 1955. The plant is the only coal-fired steam Power Station in Nigeria. Water from
the nearly Oji River is used to feed the steam turbines and also for cooling purposes
8) Ijora Thermal Power Station
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Ijora Power Plant was commissioned in 1956 with coal-fired boilers which are no longer operational The
plant has a 1 32/33i transmission station that is in good condition, but its 33/11KV transformers need
replacement Although the plant is currently nonoperational, current demand for power the availability of
natural gas, and the governmen.5 programmed for gas utilization give Ijora Power a competitive
advantage. The location of the plant makes it ideal for an Independent Power Plant project.
Table 1: List of all Generating Stations in Nigeria as at 2014 (Source:
http://www.nercng.org/index.php/industry-operators/licensing-procedures/licencees?start=20 )
Name
AES Nigeria Barge Limited
Afam Power Plc
African Oxygen & Industrial
Gases Limited
Agbara Shoreline Power Limited
Akute Power Limited
Alaoji Generation Co. Ltd (NIPP)
Anita Energy Limited
Azura Power West AFrica
Limited
Benin Generation Company
Limited
Calabar Generation Company
Limited
Century Power Generation
Limited
CET Power Projects (Ewekoro)
CET Power Projects Ltd.
CET Power Projects Ltd.
CET Power Projects(Sagamu)
ContourGlobal Solutions (Nig)
Ltd
ContourGlobal Solutions (Nig)
Ltd
ContourGlobal Solutions (Nig)
Ltd
Coronation Power and Gas
Limited
Delta Electric Power Limited
DIL Power Limited
DIL Power Plc
Egbema Generation Company
Limited
Egbin Power Plc
Eleme Petrochemical Company
Limited
License Type
Generation on-grid
Generation On-grid
Afam, Rivers State
Capacity
270 MW
987.2MW
Generation Off-grid
Ikorodu, Lagos State
19MW
Generation on-grid
Generation Off-Grid
Generation on-grid
Generation on-grid
Agbara, Ogun
Lagos Water Corporation
Alaoji,Abia State
Agbara, Lagos State
100MW
13MW
1074MW
90MW
Generation on-grid
Ihovbor Benin,Edo State
450MW
Generation On-grid
Ihonvbor, Edo State
450MW
Generation On-grid
Calabar, Cross Rivers State
561MW
Generation On-grid
Okija, Anambra State
495MW
Generation off-grid
Generation off-grid
6MW
20MW
Generation off-grid
Wapco Ewekoro,Ogun State
Tinapa, Cross River State
Nigerian Breweries Limited,
Iganmu, Lagos
WAPCO Sagamu,Ogun State
Generation Off-Grid
NBC Bottling Plant,Ikeja
10MW
Generation Off-Grid
NBC Bottling plant,Apapa
4MW
NBC Bottling Plant,Benin
7MW
Generation off-grid
Sango Otta
20MW
Generation on-grid
Generation Off-grid
Generation on-grid
Oghareki,Etiope West LGA
Cement factory, Ogun State
Obajana, Kogi State
116MW
114MW
135MW
Generation On-grid
Egbema Imo State
338MW
Generation On-grid
Egbin, Lagos State
1320MW
Generation On-grid
Eleme Complex,P.H Rivers
135MW
Generation off-grid
24 | © 2014, IJAFRSE All Rights Reserved
Site Location
5MW
7MW
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International Journal of Advance Foundation and Research in Science & Engineering (IJAFRSE)
Volume 1, Issue 5, October 2014. Impact Factor: 1.036, Science Central Value: 10.33
Energy Company of Nigeria
(NEGRIS)
Energy Company of Nigeria
Limited
Enersys Nigeria Limited
Ethiope Energy Limited
Ewekoro Power Ltd
Farm Electric Supply Ltd
First Independent Power Co. Ltd
First Independent Power Co. Ltd
First Independent Power Co. Ltd
Fortune Electric Power Co. Ltd
Gbarain Generation Company
Limited
Geometric Power Ltd
Geregu Generation Company
Limited
Geregu Power Plc (BPE)
Hudson Power Limited
Ibafo Power Station Limited
Ibom Power Ltd
ICS Power Ltd
Ikorodu Industrial Power Ltd
Ikorodu Industrial Power Ltd
Ilupeju Power Limited
Income Electrix Limited
Island Power LImited
Isolo Power Generation Limited
JBS Wind Power Limited
Kaduna Power Supply Company
Limited
Kainji Hydro Electric Plc (Jebba
Station)
Kainji Hydro Electric Plc (Kainji
Station)
Knox J&L Energy Solutions
Limited
Lotus & Bresson Nigeria Limited
Mabon Ltd
MBH Power Limited
Minaj Holdings Ltd
Generation on-grid
Ikorodu, Lagos State
140MW
Generation off-grid
Nestle,Agbara,Ogun State
3MW
Generation On-grid
Generation on-grid
Generation off-grid
Generation on-grid
Generation on-grid
Generation on-grid
Generation on-grid
Generation On-grid
Ado-Ekiti, Ekiti State
Ogorode, Sapele, Delta State
Ewekoro, Ogun State
Ota, Ogun State
Omoku, Rivers State
Trans-Amadi, Rivers State
Eleme, Rivers State
Odukpani, Cross River State
10MW
2800MW
12.5MW
150MW
150MW
136MW
95MW
500MW
Generation On-grid
Gbarain, Bayelsa State
225MW
Generation on-grid
Aba, Abia State
140MW
Generation On-grid
Geregu II, Kogi State
434MW
Generation On-grid
Generation on-grid
Generation on-grid
Generation on-grid
Generation on-grid
Distribution for
Ewekoro Cement
Embedded
Generation
Generation off-grid
Generation off-grid
Embedded
generation
Generation On-grid
Geregu, Kogi State
Warawa, Ogun State
Ibafo, Ogun State
Ikot Abasi, Akwa Ibom State.
Alaoji, Abia State
414MW
150MW
200MW
190MW
624MW
Generation On-grid
Embedded
Generation
Ikorodu, Lagos State
Ikorodu, Lagos State
39MW
Academy Press,Ilupeju
NPA,PH,Rivers State
2MW
6MW
Marina,Lagos State
10MW
Isolo Lagos State
Maranban Pushit, Mangu,
Plateau State
20MW
Kudenda Ind.Area,Kaduna
100MW
84MW
Generation On-grid
Jebba, Niger State
570MW
Generation On-grid
kainji, Niger State
760MW
Generation on-grid
Generation on-grid
Generation
Generation on-grid
Ajaokuta,Kogi State
Magboro, Ogun State
Dadinkowa, Gombe State
Ikorodu,Lagos State
Agu-Amorji Nike, Enugu East
LGA, Enugu State
1000MW
60MW
39MW
300MW
Generation on-grid
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115MW
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International Journal of Advance Foundation and Research in Science & Engineering (IJAFRSE)
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Nigerian Agip Oil Co. Ltd
Nigerian Electricity Supply
Corporation (Nigeria) Limited
(NESCO)
Notore Power Ltd
Ogorode Generation Co. Ltd
(NIPP)
Olorunshogo Generation Co. Ltd
(NIPP)
Olorunsogo Power Plc (BPE)
Omoku Generation Company
Limited
Omotosho Generation Company
Limited
Omotosho Power Plc (BPE)
Paras Energy & Natural
Resources Development Limited
Generation on-grid
Okpai, Delta State
480MW
Generation on-grid
Generation on-grid
Bukuru, Plateau State
Onne, Rivers State
30MW
50MW
Generation on-grid
Ogorode, Delta State
450MW
Generation on-grid
Generation On-grid
Oluronshogo,Ogun State
Olorunsogo, Ogun State
750MW
335MW
Generation On-grid
Omoku, Rivers State
250MW
Generation On-grid
Generation On-grid
Omotosho II, Ondo State
Omotosho, Ogun State
500MW
335MW
Generation On-Grid
96MW
PZ Power Company Limited
Sapele Power Plc
Shell Petroleum Dev. Co. Ltd
Shiroro Hydro Electricity Plc
Shoreline Power Company
Limited
Supertek Electric Limited
Supertek Nig. Ltd
Tower Power Abeokuta Limited
Generation Off-grid
Generation On-grid
Generation on-grid
Generation on-grid
Ogijo,Ogun State
PZ Cussons Aba Factory, Abia
State
Sapele, Delta State
Afam VI,
Shiroro, Niger State
Tower Power Utility Limited
Ughelli Power Plc
Unipower Agbara Limited
Wedotebary Nigeria Limited
Westcom Technologies & Energy
Services Ltd.
Zuma Energy Nigeria Ltd (Gas
Plant)
Zuma Energy Nigeria Ltd(Coal
Plant)
Generation Off-grid
Genration On-grid
Generation on-grid
Generation off-grid
4MW
1020MW
642MW
600MW
9MW
500MW
1,000MW
20MW
Generation off-grid
Generation On-grid
Generation off-grid
Generation off-grid
Lafarge Wapco,Sagamu,Ogun
Ajaokuta, Kogi State
Akwete, Abia State
Abeokuta,Ogun State
Ota Industrial Estate, Ota,
Ogun State
Ughelli, Delta State
Unilever, Agbara,Ogun St.
Kuru, Jos
Generation on-grid
Sagamu, Ogun State
1000MW
Generation on-grid
Ohaji Egbema,Owerri,Imo
400MW
Generation on-grid
Itobe,Kogi State
1200MW
20MW
942MW
6MW
5MW
III. THE CHALLENGES OF NIGERIAN POWER SECTOR
Electric utility industry is the largest utility and complex industry in the whole world. Consequently, it is
prone to different challenges. These challenges differ from country to country based on how
technological inform and how effective their government is. Nigerian Power Sector hitherto is still
battling with various challenges which sometimes seem unexplainable. These challenges range from
technical to government inability to handle to industry well.
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According to a study carried out by Onohaebi O.S, [10], in the year 2009, some causes and effects of
power outages in the Nigerian Transmission Network were itemized. This is presented in table 2. These
outages occurred in transmission network for 2004 and 2005. The problems were grouped into
transmission lines constraints, shunt reactor problems, overloading of transformers and vandalization of
the lines.
Table 2: Summary of transmission network faults, causes and effects [10].
LINE
FAULTS
EFFECTS ON THE
NETWORK
Ikorodu-Ayede-Oshogbo Frequent
Circuit
was Frequent and prolonged
132kV
conductor/jumper
constructed in 1964 outages on the circuit.
cut
along
entire and is aging
length
Akangb-Ojo 132kV
Frequent earth fault
Reduction of overhead Frequent forced outages on
clearance
refused the circuits.
burning
due
to
proliferation of houses
and stations. Industrial
pollution of lines and
insulators
due
to
heavy refuse dumps
and heavy industrial
built up reported since
1983
Gombe-Maiduguri 132kV Large voltage drops Line is single circuit Gombe 132kV bus has to
circuit
of 20-40kV between and is too long run as high as 140-145 kV
enable
acceptable
Gombe
and (310km)
conductor to
Maiduguri
size is also small voltage levels at Maiduguri
Gombe 132kV has to be
150mm2
run split.
New-Haven-OturkpoAbout 20kV voltage Single
line New Haven 132kV bus
Yander
drop between New configuration
using voltage had to run high
Haven and Yander
150mm2 and line is voltage
330km long
Benin-Onitsha-Alaoji
Constant tripping of Limited by single line Frequent shutdown of
330kV
Benin-Onitsha-Alaoji
contingency
voltage Afam Power station due to
line
control problems
transmission line faults
thus stressing the Afam P.S.
units.
Restoration
of
Electricity
supply
prolonged due to voltage
control problems. About 11
states
capitals
and
environs
experienced
prolonged blackouts.
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Aba-Itu 132kV line
Delta-Benin 132kV DC
Delta/Sapele/Aladja
Frequency of tripping Breakdown of only 1
of line
circuit breaker on the
line with no provision
for by-pass facilities
and is limited by single
line contingency
Several
spans
of Poor Maintenance and
collapsed towers
aging
Poor
configuration
leading
to
poor
maintenance
and
operation of Aladja
Steel switch gear by
PHCN
Reactors: Onitsha 9 Rs- Reactor out of circuit
30 MX
Oshogbo 4R1-75 MX
Birnin-Kebbi
MX
Reactor out of Service
19R1-30 Reactor out of Service
Prolonged blackout of Itu,
Eket and Calabar complex
serving the majority of
cross River and Akwa Ibom
State.
No output for Delta O.S
generation through the
inter-bus transformer to
Benin
Transmission
Station on 132kV
The arrangement is Fault tracing/clearing is
defective since power very precise and energy
flows
from metering is difficult
Sapele/Delta
Steel
Power Station through
Aladja Delta Steel
Company
Low resistance causes High voltages experienced
the reactor to be out of at Onitsha and New Haven
Circuit
substations respectively.
When Afam Power Station
generation is separated, it
took
long
time
to
synchronize the station to
the grid because of high
voltage
difference,
resulting in many areas
thrown into darkness
Faulty winding
Excessive high voltage at
Oshogbo
Burnt
underground High voltages at Birnin
cable
Kebbi above limits
Sambo, A.S, 2005, [11] also presented a paper which noted the causes of inefficient and unreliable energy
supply system in Nigeria. In electric energy supply efficiencies of existing thermal plants are low. They
are as low as 12% whereas efficiencies of up to 40% are attainable with modern technologies. Also
substantial electricity is lost during transmission and distribution. These losses are sometimes more than
30% of the total electricity generated. Apart from these inefficiencies the reliability and availability of
existing installed electric generation system is low. There is the serious problem of power unreliability
over the years such that most industrial establishments and upper income households install very
expensive generating sets amounting to over half of the total installed grid capacity. This constitutes huge
economic losses to the Nigerian economy.
According to [11], the major factors contributing to the above unreliability and inefficiency in the power
sector are:
(a) Frequent breakdown of generating plants and equipment due to inadequate repairs and maintenance;
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(b) Lack of foreign exchange to purchase needed spare parts on time
(c) Obsolete transmission and distribution equipment which frequently breakdown
(d) Lack of skilled manpower; as well as
(e) Inadequacy of basic industries to service the power sector.
According to [12], the challenges include the following:
•
•
•
•
•
•
•
•
Radial Lines with no redundancies
Obsolete Substation Equipment
Overloaded transmission lines and Substations
Inadequate Coverage of Infrastructure
Limited Funds for Development projects
High Technical and Non-Technical loss
Limited training opportunities
Community issues during project execution
Idigbe and Igbinovia, 2010, [13], posited the following as the challenges facing power sector in Nigeria.
•
•
•
•
•
•
The long period of reliance on hydro-stations, as primary sources of generating electric power.
The industry had ample time to supplement power generation through alternative sources –
thermal, coal, wind, etc., but wasted all the years through failed policies on dams.
Poor policies on natural gas - its effective development. Natural gas has always been looked at, as
a nuisance from crude oil production until lately, when the Federal Government suddenly realizes
that it can be used for power generation. The so-called gas master plan is not an effective policy
for the proper development of our vast resources of natural gas.
Poor pricing of electricity,
Obsolete facilities: Many of the gas plants are not working, and are old. Pipelines are constantly
under threats of being compromised. When they are working, maintenance of the facilities are
not carried out as and when due.
Funding, and
Social factors
Discussion of results of Onohaebi and Lawal, 2010, [14] concluded on the poor state of maintenance of
the power stations could be attributed to the Nigerians’ attitude towards maintenance, poor funding,
unskilled manpower, lack of adequate training, over-aged and obsolete equipments. These Infact would
contribute to the poor state of Nigerian Power Sector.
Figure 1: Nigeria Annual Fund released to the Power Sector 1974 – 2003[14].
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Figure 2: Age range of generation plants.
IV. CASES OF SYSTEM COLLAPSE
System collapse’ is the term used to describe the situation when all the power generating stations
connected to the grid shut down at the same time or immediately one after the other, leaving the entire
area supplied by the grid (the whole country, in the case of the Nigerian grid) in blackout. Generating
plants may shut down as a result of human deliberate control action as part of normal operational
scheduling, or automatically as a result of self-protective action.
An interview conducted by This Day Live and reported by Foluseke A. Somolu on the 25th August, 2013
gave clear explanation on the causes of system collapse in the country. This report is given as it were
below:
Self-protective shutdown of generators may be initiated by protective relays installed on the generating
plant reacting to any one or combination of potentially harmful operational development within the
power station or individual generator. It may, on the other hand be as a result of happenings on the grid,
external to the generating plant, but which have the potential to impose operational duties on the
generator beyond its capability. One of such is when the system operating frequency falls outside the
allowable deviation from the nominal level stipulated for the generating plant. The system nominal
frequency applicable to all generating plant and electrical appliances in Nigeria and many other countries
is 50Hz (50 cycles per second). (The exceptions are in the Americas, north and south, where it is 60Hz).
Thermal stations (i.e. those burning some form of fuel, especially the steam stations), due to their many
pumps and motors controlling critical functions, are more sensitive to low frequency than hydro stations.
But all of them, whether hydro or thermal, will eventually shut down when the frequency falls low
enough, and then a system collapse results.
We may ask what causes the system frequency to fall. A load demand imposed on the grid greater than
the combined capacity of all the connected generating stations will cause the system frequency to fall.
With our low generating capacity (4000MW) in comparison to our country’s actual demand, it is obvious
we will always be operating in the vicinity of low system frequency. When the increase in load demand is
due to consumers, the rate of fall in the system frequency is gradual and the speed governors of each
generator can take some corrective action automatically by boosting the fuel input to the generator to
increase its speed, and hence the frequency, provided the generator had not been fully loaded up to that
point. This is similar to when, upon approaching a hill, the driver of a truck changes gear and presses
down harder on the accelerator pedal of the truck. Good system operating practice requires that one or
more generators in the grid are deliberately only partially loaded so there is ample and readily available
spare capacity, called “spinning reserve”, to absorb unplanned sudden load demand placed on the grid
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such as when a huge industrial consumer comes on line, or a generating plant is shut down by its own
self-protective action thereby placing a heavy load demand on the remaining generating stations.
When these automatic actions, i.e. the combination of the speed governors and the spinning reserve, fail
to arrest the frequency drop, the system operators at the National Control Centre who are monitoring the
state of the power system and noticing the dropping system frequency, can intervene ‘manually’ and
instruct one or more power stations to start and bring up additional generating plant. They can in
addition instruct a substation to disconnect some consumers to reduce the system load demand.
Nowadays the system operators are not able to establish communication with stations quickly enough to
arrest the impending collapse. This is because the SCADA (i.e. Supervisory Control and Data Acquisition)
that enables the system operator monitor happenings at all grid stations, as well as the special “no fail”
communications facilities built for instant linkup between the control centre and all stations when the
grid was being developed in 1960s -1980s and which were still functioning up to the mid 1990s, are all
now virtually broken down or not even there anymore. The voice communications have been largely
replaced with GSM phones but their ‘network problems’ and ‘subscriber not available’ messages, and
other interruptions obviously make the use of GSM completely unsuitable for this function.
Another scenario in which the system frequency falls is when the system overload is caused by a fault (i.e.
a short-circuit) on any one of the many transmission lines that make up the grid. Since many thousands
of kilometers of our transmission lines pass through heavy forests, the possibility of vegetation fouling
the lines and causing faults is ever present, except the line trace is cleared of all vegetation up to
15metres on either side of the line for the whole length of the line, which is easier said than done,
especially because of the heavy costs and logistics involved.
These line faults represent very heavy load demands that require every generating plant on the grid to
contribute multiples of its capacity, which of course, is impossible. Here we have a “double jeopardy”
situation. Apart from the overload placed on each generator, which is harmful on its own, the system
frequency also drops very sharply and beyond allowable thresholds. The system protective relays should
normally remove the faulted line from service promptly before the generators’ self-protection relays
react. But they can only do so, if they act in a coordinated manner, i.e. if they are properly calibrated and
their settings coordinated with each other, and also provided the communications links between them
are functioning. Again it is doubtful if this is still so nowadays. Protection engineers, specialists in their
own right, whose function it is to calibrate and ensure proper coordination of these relays are an
endangered species in the power industry nowadays. Also, as has been mentioned earlier, most teleprotection communication channels in the power system are no more functioning as they used to. Line
faults are therefore usually removed too slowly. The ‘last ditch’ provision to save the system from
collapse in this situation then is the underfrequency emergency load-shedding arrangement. But it is not
always very effective because the consumers on the feeders it removes from service may not have their
total load anywhere close to the demand imposed on the system by the fault, and a system collapse still
occurs.
Now why blackouts due to system do collapses last so long? The major problem encountered during
restoration following a system collapse is the time required to restart the generating plants. The thermal
stations pose the biggest challenge. They cannot remain spinning when they have no load connected to
them and usually shut down when system collapses occur. And when they shut down, they eject their
steam they have built up and depend upon to operate. This is in order to avoid dangerous steam pressure
buildup. It takes about six to ten hours to raise new steam and start operation again. And when they are
restarted, they have to be loaded in small increments, allowing them to stabilize at each load level before
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taking on additional consumers. Sometimes the anxiety to load the generators quickly and shorten the
system blackout may lead to taking on too much load at a time and cause a generator to shut down again
and return the operators to the beginning all over again. All this while, the national control centre (NCC)
is abuzz with activities, talking to and passing instructions to all the power stations and grid-connected
substations across the country, coordinating the restoration efforts.
Even as simply as one has tried to describe it, the foregoing should have shown that maintaining the
integrity of the grid consists of a series of many and painstaking activities, many of them highly
specialized. It also requires the continuous availability of many facilities for the operators of the grid, as
has been mentioned earlier, over and above simply building of power stations and substations in various
parts of the country, and transmission lines to link them to each other. These facilities include but are not
limited to the Supervisory Control and Data Acquisition (SCADA) and no-fail voice communications that
must work even in the face of national power blackout.
And having made this point, one should also add that while it may not be possible to totally avoid system
collapses, their frequency can definitely be drastically reduced. In fact in 1992 the country recorded zero
system collapses. In the few years preceding that year (1992), through the determined efforts of the staff
and the cooperation of Management (through the provision of funds), the coordination of the protective
schemes in the grid was highly improved, most of the inconsistencies in the relay settings having been
‘debugged’; the SCADA having just been commissioned and put to use in the country’s power system for
the first time, and the power system communications facilities being maintained in correct working
order. Staffs at that time were also very well trained to have been able to do the operation and
maintenance work required at the highest standards. So if we really want to reduce or eliminate system
collapses, government needs to look into all these[14].
Table 3: System collapses for the period of 2000-2003 [15].
Year
Partial
Collapse
Total Collapse
Total System
Collapse
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
6
5
5
14
32
9
39
14
30
22
15
21
10
21
8
18
16
26
20
19
11
19
41
53
52
36
31
26
42
39
2010
2011
2012
2013
42
19
24
OVER 15
V. CONCLUSION
From the review of the Nigerian Power Sector hitherto, it can be concluded that to have a way out of the
problems and challenges facing the sector, the following points must be adhere to.
• Replacement of old and obsolete power system equipments;
• Establishment of more generating stations;
• Embarking on ring transmission network;
• Incorporating FACTS device for loss compensation;
• Strong protection system;
• Proper maintenance culture; and
• Adequate funding of the sector.
VI. REFERENCE
[1]
Niger Power Review: Development of the Electricity Industry in Nigeria (1960-1985) , 1985, pp.
1-6.
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Volume 1, Issue 5, October 2014. Impact Factor: 1.036, Science Central Value: 10.33
[2]
A. S. Sambo, B. Garba, I. H. Zarma and M. M. Gaji, “ Electricity Generation and the Present
Challenges in the Nigerian, Power Sector”, Energy Commission of Nigeria, Abuja-Nigeria.
[3]
O I Okoro, E Chikuni, “Power sector reforms in Nigeria: opportunities and challenges”, Journal of
Energy in Southern Africa • Vol 18 No 3 • August 2007.
[4]
James k, and Okafor F.N, “Automatic Generation Control Performance of the Nigerian Power
System After Deregulation.
[5]
A. S. Sambo, “Matching Electricity Supply with Demand in Nigeria”, Fourth Quarter 2008.
[6]
Mohiuddin, Arif (2011). “The Privatization Transaction Process and the Opportunities for
Investments in the Nigerian Power Sector.” Electric Power Sector Reform Workshop, Abuja, May
25.
[7]
Presidential Task Force on Power (2011a).www.nigeriapowerreform.org/index.php/refrm
institutions/overview . Accessed on September 30, 2011. —. (2011b). “Nigeria's Power Crisis:
Light at the End of the Tunnel.” Abuja: Federal Government of Nigeria.
[8]
Engr. Oladele Amoda, “Lingering Issues In The Nigeria Power Market”, Eko Electricity
Distribution Company Lagos, Nigeria Seminar On Dividends Of Privatization Of Power Sector,
September, 2014.
[9]
http://www.nercng.org/index.php/industry-operators/licensing procedures/licencees?start=20
[10]
Onohaebi O.S, “Power Outages in the Nigeria Transmission Grid”, Research Journal of Applied
Sciences 4(1): 1-9, 2009.
[11]
Sambo A.S, “Renewable Energy For Rural Development : The Nigerian Perspective”, ISECO
Science and Technology Vision, Vol 1 – May 2005 (12-22).
[12]
Labo H.S., “Current Status and Future of the Transmission Network”, Investors’ forum for the
Privatisation of PHCN successor companies, 2010.
[13]
K.I. Idigbe, S.O. Igbinovia, “ASSESSING THE SUSTAINABILITY OF ELECTRIC POWER IN NIGERIA: A
CASE STUDY OF THE IPPs”, Journal of Economics and Engineering, ISSN: 2078-0346, February,
2010.
[14]
O.S. Onohaebi And Y.O. Lawal, “Poor Maintenance Culture; The Bane To Electric Power
Generation In Nigeria”, Journal Of Economics And Engineering, ISSN: 2078-0346, May, 2010.
[15]
http://www.thisdaylive.com/articles/why-we-ve-power-system-collapses-and-why-they-last-solong/157212/
Energy Mix Report, “Power Transmission: Over 139 system collapses recorded in five years”, Jan
14, 2014.
[16]
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