Reliability Assessment of Major Feeders of the Atoabo Substation,  
Tarkwa Using Autorecloser-Based ETAP Simulation  
J. K. Annan1* and J. M. Yevunya2  
1University of Mines and Technology, Tarkwa, Ghana  
2Electricity Company of Ghana, Ahomaso, Kumasi, Ghana  
Received: 30 November 2025; Accepted: 06 December 2025; Published: 19 December 2025  
ABSTRACT  
Reliable Medium Voltage (MV) distribution networks are critical to economic activities in Ghana, particularly  
in mining-intensive municipalities such as Tarkwa, where prolonged outages impose substantial operational  
losses. This study evaluates the reliability performance of the 11 kV Town 1, Town 2 and Manganese feeders  
supplied from the Atoabo Bulk Supply Point (BSP), a strategically important node feeding high-value industrial  
and residential loads. Six years of outage data (20162021) were analysed and used to calibrate an ETAP  
probabilistic reliability model, addressing the absence of simulation-based reliability evaluation and automation-  
planning studies for Ghanaian MV distribution networks. The calibrated ETAP model replicated historical SAIFI  
and SAIDI values within ±510%, confirming strong model fidelity. Simulation results show that ACR  
deployment yields significant reliability improvement at SAIFI reduction of 3540% on Town 2, SAIDI  
reduction of 3235% on Manganese feeder, and overall reliability improvement of 2530% on Town 1. The  
findings demonstrate that targeted MV automation at Atoabo BSP provides a cost-effective and high-impact  
reliability intervention, capable of reducing cumulative annual customer interruption duration by over 100 hours  
per feeder. This work provides an investable pathway for Electricity Company of Ghana to achieve Public  
Utilities and Regulatory Commission’s reliability benchmarks in similar radial distribution environments.  
Keywords: Reliability Analysis, Distribution Automation, Automatic Circuit Recloser (ACR), ETAP  
Simulation, Power Distribution Network, System Interruption Indices, Tarkwa Municipality.  
INTRODUCTION  
Electric power reliability remains a key determinant of socio-economic development in many developing  
economies, where interruptions in distribution networks impose large costs on industry, households and public  
services. In Ghana, distribution-level outages are a major contributor to unreliable supply and elevated customer  
interruption indices (SAIDI, SAIFI), particularly in mining municipalities where continuous power is critical for  
operations and safety. The present study uses six years of outage data from the Atuabo Bulk Supply Point  
(Atoabo BSP) to evaluate reliability of the 11 kV Town 1, Town 2 and Manganese feeders and to test the  
reliability benefit of targeted Distribution Automation (DA) interventions using ETAP simulations.  
Recent research indicates that distribution automation which includes automatic circuit reclosers (ACRs),  
sectionalizers, remote fault indicators and SCADA-enabled feeder control can materially reduce outage  
frequency and duration when deployed in contexts with high rates of transient and vegetation-related faults. Case  
studies and modelling work from the region demonstrate measurable SAIFI/SAIDI improvements following the  
installation of reclosers and sectionalizers, and highlight that even modest automation investments can yield  
substantial reliability and commercial benefits in utilities with limited operational staff and manual switching  
processes.  
However, the distribution automation literature also emphasises that the performance gains and cost-  
effectiveness of DA are highly context dependent: feeder topology, fault mix (transient versus permanent),  
communication infrastructure, and existing switching points determine where devices like ACRs produce the  
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greatest benefit. Comparative studies from Nigeria and South Africa suggest that DA implementations should  
be guided by localized reliability data and simulation-based evaluation before large-scale rollout.  
This study therefore integrates historical outage analysis for the Atoabo BSP (20162021) (ECG, 2022) with  
ETAP-based simulation experiments to quantify the reliability impact of selected automation schemes (ACRs  
and sectionalizers) on the Atoabo 11 kV feeders. The objective is to provide an evidence-based, simulation-  
driven justification for prioritised automation investments in the Tarkwa Municipality that are aligned with  
PURC benchmarks and local operational constraints.  
Reliability Challenges in Ghana’s Distribution Networks  
Ghana’s national studies on distribution performance provide a useful backdrop, but reliability challenges vary  
substantially between metropolitan and mining municipalities. Tarkwa’s Atoabo BSP supplies several large  
mining customers and dense residential clusters via three principal 11 kV feeders (Town 1, Town 2 and  
Manganese). Field data from ECG’s Atoabo records show elevated SAIFI and SAIDI on these feeders (average  
SAIFI and SAIDI over 20162021 for the Manganese feeder are 84 and 88.9 hr/customer·yr respectively), and  
the network operates without SCADA or automated feeder devices. These locally observed characteristics  
including high transient-fault share, long restoration times and absence of feeder automation motivate a targeted,  
simulation-based evaluation of ACR and sectionalizer placements at Atoabo rather than relying on generic  
country-level prescriptions.  
Technological Interventions for Reliability Improvement  
Modern reliability enhancement strategies are increasingly centered on automation and smart grid technologies.  
Devices such as Automatic Circuit Reclosers (ACRs), sectionalizers, and Fault Path Indicators (FPIs) enable  
remote fault detection, automatic isolation, and rapid service restoration (Elkadeem et al., 2017).  
Autoreclosers, in particular, have become vital components of self-healing distribution networks. They  
automatically open during a fault, test the circuit, and reclose after a short delay, thereby restoring supply if the  
fault was transient (Rones and Vittal, 2013). Studies by Mehdi et al. (2021) and Singh (2017) demonstrated that  
autoreclosers can reduce outage duration by up to 60% and prevent cascading failures in radial systems. In the  
Ghanaian context, the integration of autoreclosers at strategic points in the network has shown potential to  
significantly improve reliability and operational efficiency.  
Simulation software such as ETAP (Electrical Transient Analyzer Program) has become a standard tool for  
analyzing, modeling, and improving power system reliability (Idowu et al., 2021). The Reliability Assessment  
Module (RAM) of ETAP allows engineers to compute probabilistic reliability indices, perform contingency  
analysis, and evaluate the effect of equipment upgrades like autoreclosers or sectionalizers.  
LITERATURE OVERVIEW  
Overview of Electric Power Systems  
An electric power system, which consists of three interdependent subsystems namely generation, transmission,  
and distribution, is aimed at ensuring reliable and economical energy delivery to end-users (Kumar et al., 2018).  
While generation and transmission systems are generally well protected and redundant, the distribution network  
is more vulnerable to faults because of its extensive exposure to environmental, mechanical, and human  
interferences (Chandhra et al., 2017).  
Distribution systems typically operate at medium voltages (11 kV 33 kV) for bulk supply and low voltages  
(400/230 V) for end-user consumption. They are mostly radial in topology, making them highly susceptible to  
single-point failures. As a result, more than 80% of customer outages originate at the distribution level (Ghiasi  
et al., 2019).  
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Power System Reliability Concepts and Reliability Indices  
Reliability in electrical systems refers to the probability that a power network will perform its intended function  
without interruption for a specified period under defined conditions (IEEE Power & Energy Society, 2012).  
Power system reliability is generally divided into two conditions:  
i.  
The system’s ability to meet load demands under normal operating conditions; and  
ii. The ability of the system to withstand sudden disturbances such as faults, line outages, or equipment failures  
(Kumar et al., 2018).  
Distribution Automation in Developing Economies  
Recent studies have examined Distribution Automation (DA) in low and middle income settings and reported  
the following consistent findings:  
i.  
Simulation and field studies indicate that well-placed ACRs and sectionalizers produce significant  
reductions in SAIFI and SAIDI on radial feeders dominated by transient faults. ETAP and similar platforms  
are commonly used to quantify expected gains prior to deployment;  
ii. The magnitude of improvement depends on feeder topology, fault type composition (momentary vs  
permanent), and communication or maintenance capability; and  
iii. In many utilities in Sub-Saharan Africa, limited SCADA, weak communications and constrained operations  
and maintenance budgets slow adoption despite clear technical benefits.  
Comparative Regional Studies  
In Nigeria, several utility-level and academic studies report reliability improvements after selective automation  
and protection upgrades in Nigerian distribution networks. These works highlight the practical benefits of  
reclosers and sectionalizers in networks where vegetation and temporary faults are dominant causes. They also  
underscore the need for communication and maintenance planning to ensure devices remain effective (Akande  
et al., 2021). In South Africa, Eskom-oriented research and municipal studies emphasise automation integrated  
with network reconfiguration and improved switching practices; South African work typically stresses a  
combined techno-economic approach (which included automation, network reconfiguration, and targeted  
maintenance) to maximise benefit under constrained budgets (Gumede and Saha, 2022).  
Although regional studies document the technical potential of distribution automation, there is a lack of site-  
specific, simulation-based assessments for the Atoabo feeders that combine the actual ECG outage record (2016–  
2021), realistic device models and placement optimisation using ETAP. Existing Ghanaian reliability work has  
largely been descriptive or pilot-scale; it has not produced a combined historical-plus-simulation analysis  
tailored to a mining-intensive feeder set such as Manganese/Town 1/Town 2 at Atoabo. In short: a simulation-  
based assessment of automation solutions for Atoabo feeders (quantifying SAIFI/SAIDI/EENS reductions and  
energy savings under realistic device placements and coordination settings) is missing.  
Many case studies report substantial benefits from ACRs but also emphasise that field performance depends on  
the proportion of temporary or transient faults, correct coordination and setting of shots/dead-time and  
communication and maintenance to prevent device misoperation (Mandefro and Mabrahtu, 2020; Gumede and  
Saha, 2022). These lessons map directly to Atoabo where the historical data indicate ~49% transient faults.  
Resources and Methods Used  
Objectives, Data Review and Methods  
The objectives of this research are to quantify baseline reliability of the Atoabo BSP 11 kV feeders (Town 1,  
Town 2 and Manganese) from ECG outage records (20162021) and benchmark against PURC standards, and  
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then evaluate the reliability impact of targeted distribution automation (automatic circuit reclosers and  
sectionalizers) using ETAP-based simulation scenarios and compute expected changes in SAIFI, SAIDI, CAIDI  
and EENS.  
Operational data were obtained from the Electricity Company of Ghana (ECG) Regional Office in Takoradi and  
the Tarkwa District Office. The dataset covered a six-year period (20162021) and included feeder interruption  
frequencies, outage durations, causes, restoration times, load profiles, and network topology. Field visits were  
conducted to the Atuabo Bulk Supply Point (BSP) to verify network parameters and record equipment  
specifications, including transformer ratings, conductor sizes, and circuit breaker types. Additional data were  
gathered on customer population, installed capacity, and load demand patterns.  
The study focused on the 11 kV distribution feeders made up of Town 1, Town 2, and Manganese feeders  
supplied from the Atuabo BSP in the Tarkwa Municipality of Ghana’s Western Region. The BSP receives 33  
kV supply from GRIDCo and steps it down to 11 kV through a 20 MVA, 33/11 kV transformer. The 11 kV  
network operates on a radial configuration using 120 mm² aluminum conductors and serves approximately  
21,500 customers via 117 distribution transformers with a total installed capacity of 22.67 MVA. Circuit  
protection is provided by Vacuum Circuit Breakers (VCBs) on the 11 kV side and SF₆ circuit breakers on the 33  
kV side. The system currently operates without SCADA or automation facilities.  
Reliability analysis was conducted using the historical assessment method, employing standard indices such as  
System Average Interruption Frequency Index (SAIFI), System Average Interruption Duration Index (SAIDI),  
Customer Average Interruption Duration Index (CAIDI), Average System Availability Index (ASAI), Expected  
Energy Not Served (EENS), and Average Energy Not Served (AENS). These indices were computed based on  
outage data using Equations (1)(8) defined in IEEE Std. 1366 (2012). The computed values were benchmarked  
against the PURC thresholds (SAIDI ≤ 48 hr/customer·yr; SAIFI ≤ 6 interruptions/customer·yr).  
Outages were categorized into planned and unplanned types. Planned interruptions involved scheduled  
maintenance or installations, while unplanned outages resulted from faults such as transient disturbances,  
lightning strikes, equipment failures, and conductor breakages. Fault classification followed standard  
distribution fault categories including single line-to-ground, line-to-line, double line-to-ground, and three-phase  
faults, as summarized by Gupta (2019) and Grainger and Stevenson (2016).  
Rationale for Data Timeframe (20162021)  
The six-year dataset (20162021) was selected because it represents the most complete, consistent and validated  
outage record available in the Atoabo BSP logbooks, covering both pre- and post-network modification periods.  
The timeframe includes periods of abnormal system stress (notably 2016), transitional operational improvements  
(20172018), and relative supply stability (20192021), offering a statistically representative window of the  
feeder behaviour.  
Although more recent data (20222023) are desirable, these years exhibited incomplete logging due to COVID-  
19 staffing constraints and SCADA-less manual reporting inconsistencies, issues reported for several  
developing-economy utilities (Ogunjuyigbe et al., 2021; Kahimba and Mbuli, 2022). The 20162021 series  
therefore provides the most reliable and continuous basis for trend computation, index averaging, and ETAP  
model calibration.  
Reliability Indices in Distribution Systems  
Reliability indices are standardised metrics that help utilities quantify outage performance, compare feeder  
conditions, and monitor compliance with regulatory benchmarks (Manandhar, 2013). Common indices are  
presented in Table 1.  
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Table 1 Summary of Reliability Indices  
Rel. Index Definition  
Description  
Unit of Measure  
SAIFI  
System Average Interruption Mean number of sustained interruptions a fr/cust.yr  
Frequency Index  
customer experiences at a predefined period  
in the system.  
SAIDI  
CAIDI  
MAIFI  
ASAI  
System Average Interruption Total duration of interruption for the average hr/cus.yr  
Duration Index  
customer during a predefined period.  
Customer  
Average The average time required to restore service.  
hr/cust.  
Interruption Duration Index  
interruption  
Momentary  
Average This is a measure of the average frequency of fr/cust. yr  
Interruption Duration Index  
momentary interruptions.  
Average System Availability  
Index  
Fraction of time that a customer has received Per unit  
power during reporting period.  
EENS  
ACCI  
Expected Energy Not Served  
Mean energy not supplied per customer per MWh/yr  
year.  
Average  
Customer kWh of connected load interrupted for each kVA/ customer  
affected customer in one year.  
Curtailment Index  
ECOST  
IEAR  
Expected Interruption Cost Cost of energy not supplied at load point.  
Index  
$/yr  
Interrupted  
Energy This is the cost per unit of unserved energy.  
$/kWh  
Assessment Rate  
Utilities use the indices of Table 1 to assess feeder-level performance and prioritise reliability investments. The  
PURC of Ghana stipulates benchmark values of SAIDI ≤ 48 hr/customer·yr and SAIFI ≤ 6  
interruptions/customer·yr (PURC, 2022).  
Equation 1 through to Equation 8 give the mathematical definitions of the most frequently used reliability indices  
mentioned in Table 1.  
휆 푁  
푆퐴퐼퐹퐼 =  
(1)  
where,  
n = total number of load points  
λi = avg. failure rate of each segment i (f/yr)  
Ni = number of customers interrupted  
Nt = total number of customers served  
푈 푁  
푆퐴퐼퐷퐼 =  
(2)  
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where is the average annual outage time at load point i (f/yr).  
푈 푁  
ꢂꢃꢄꢅꢄ  
ꢂꢃꢄꢆꢄ  
퐶퐴퐼퐷퐼 =  
푀퐴퐼퐹퐼 =  
=
(3)  
(4)  
휆 푁  
휆 푁  
ASAI is the ratio of customer hours of service availability to customer hours of service demand.  
8760푁 −  
푟 푁  
푖 푖  
1−ꢂꢃꢄꢅꢄ  
퐴푆퐴퐼 =  
=
(5)  
8760푁  
8760  
where ꢇ = ꢈ표ꢈ푎푙 ꢇ푒푠ꢈ표ꢇ푎ꢈꢉ표ꢊ ꢈꢉ푚푒.The number 8760 represents the number of hours in a regular year.  
퐴푆ꢀ퐼 = 1 퐴푆퐴퐼  
(6)  
퐸퐸ꢋ푆 = 푃 ꢀꢁ  
(7)  
EENS is basically interpreted as a product of the average load and the output duration.  
ꢍꢍ푁ꢂ  
퐴퐸ꢋ푆 =  
(8)  
AENS represents the ratio of the expected energy not served to the total number of customers served.  
Faults in Distribution Systems  
Faults in electrical distribution systems are unintended deviations from normal operating conditions that cause  
abnormal currents or voltages in power circuits. They can result from equipment failure, insulation breakdown,  
weather conditions, mechanical damage, or human error. Distribution systems, being the final stage of power  
delivery to consumers, are particularly vulnerable to such disturbances due to their wide geographical spread  
and exposure to environmental factors.  
Understanding the nature, causes, and effects of various faults is essential for the design of reliable protection  
schemes, ensuring continuity of supply, safety of personnel, and longevity of equipment. Table 2 summarises  
the major types of faults that occur in electrical distribution networks, outlining their causes, effects, and common  
protection or mitigation measures employed in modern power systems.  
Table 2 Summary of Faults in Electrical Distribution Systems  
Type of Fault Meaning  
Typical  
Causes  
Effects on System  
Method  
Detect  
to Ways  
Mitigate  
to  
One  
Line-  
phase Insulation  
Unbalanced  
currents,  
dips, over-voltages residual  
Earth  
voltage relays,  
fault Earth fault relay  
+ circuit breaker  
Single  
conductor touches breakdown,  
earth or grounded lightning,  
to-Ground  
(LG)  
surface  
moisture,  
pollution  
on healthy phases  
current  
detection  
Two  
conductors  
into contact  
phase Tree branches, High fault current, Over-current  
Over-current  
or differential protection, phase  
relay segregation  
Line-to-Line  
(LL)  
come conductor  
swing,  
unbalanced  
voltages,  
damaged  
overheating  
insulation  
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Two  
phase Flashovers,  
Severe current flow Earth fault and Ground  
fault  
Double Line-  
to-Ground  
(LLG)  
conductors contact heavy  
each other and the lightning,  
through  
path,  
ground over-current  
voltage relays  
protection, surge  
arresters  
ground  
mechanical  
failure  
unbalance  
All  
three Severe  
Very high current, Over-current  
High-speed  
circuit breakers,  
fuses  
Three-Phase  
(Balanced)  
Fault  
L)  
conductors shorted insulation  
maximum  
relays,  
together  
(LL–  
failure,  
equipment  
breakdown  
mechanical stress  
differential  
relays  
All three phases Major  
shorted to ground equipment  
Extremely  
fault current, system and  
collapse  
high Difference  
Auto- reclosing  
Three-Phase-  
to-Ground  
(LLLG)  
over- breakers,  
current relays clearing  
fast  
same time  
failure,  
lightning  
One  
or  
more Mechanical  
Unbalanced  
Under-voltage Reclosing  
single or negative scheme,  
open phasing in motors sequence maintenance  
relays inspection  
Open Circuit  
Fault  
conductors broken damage, broken voltages,  
(no current flow)  
lines,  
switches  
Conductor touches Fallen  
poor conductor conductors,  
such as asphalt or degraded  
Low but dangerous Special  
fault current, fire detection  
risk  
HIF Arc  
detectors,  
algorithms isolation relays  
fault  
High  
Impedance  
Fault (HIF)  
dry soil  
insulation  
Electric  
between  
conductors or to damaged  
ground insulation  
arc Loose  
connections,  
Voltage  
equipment  
degradation and fire relays,  
harmonic  
analysis  
flicker, Arc  
detection  
fault Arc  
restraint  
Arcing Fault  
coils, insulation  
care  
(Sources: Gupta, 2019; Grainger and Stevenson, 2016)  
Atuabo Bulk Supply Point  
The Atuabo Bulk Supply Point (BSP) is a substation located in the Tarkwa Municipality of the Western Region  
in the Republic of Ghana. It is one of the substations in the Region where ECG takes bulk of its electric power  
supply to serve customers in Tarkwa, Abosso, Prestea, Damang and surrounding communities. Mining  
companies such as Goldfields Ghana Limited, Ghana Manganese Company and African Mining Services as well  
as institutions like UMaT, Fiaseman and Tarkwa Senior High Schools also take supply from the Substation.  
There are four feeders from the national grid to the substation. These feeders supply four transformers namely  
9T1, 9T2, 9T3, and 9T4 with voltage levels of 161 kV. Each feeder is connected to a 26/33 MVA, 161/33 kV,  
step-down transformer at the GRIDCo side of the system.  
The 33 kV incoming feeders from GRIDCo is connected to the ECG busbar through Sulphur hexafluoride (SF6)  
gas circuit breakers and isolators. Potential Transformers (PTs), Current Transformers (CTs), relays, and other  
auxiliary equipment are used to design the protection and metering systems. ECG again steps down the voltage  
through a 20 MVA, 33/11 kV transformer for distribution.  
There are three outgoing 11 kV feeders and three outgoing 33 kV feeders. These are Town 1, Town 2 and  
Manganese for the 11 kV lines and Bonsa, Abosso 1 and Aboso 2 for the 33 kV feeders.  
Page 977  
The busbar arrangement at the Atoabo substation is a sectionalized single busbar system. In this arrangement a  
circuit breaker and isolating switches are used to sectionalize the bus. This arrangement enables maintenance to  
be carried out on one part of the system without a complete shutdown of the entire station. Fig. 1 shows a single  
line diagram of the Atoabo Substation modelled with ETAP 19.0 software.  
Fig. 1 Busbar Arrangement at Atoabo Substation  
The 33 kV busbars are outdoor, and the 11 kV busbars are indoor. Monitoring and operation are carried out  
through indoor panels for both voltage levels. There is no SCADA facility at the ECG side of the substation.  
Circuit Breakers and Other Infrastructure  
Two types of circuit breakers are employed at the Atoabo substation: Gas Insulated Switches (GIS) containing  
sulfur hexafluoride (SF6) circuit breaker for the 33 kV system and Vacuum Circuit Breaker (VCB) for the 11 kV  
system. Fig. 2 shows the outdoor SF6 circuit breakers at the substation. Fig. 2 and Fig. 3 show the indoor panels  
of both 33 kV and 11 kV system while Fig. 4 indicate the rectifier and batteries used in the substation.  
Fig. 2 Atoabo Substation 33 kV Indoor Panels  
Fig. 3 Atoabo Substation 11 kV Indoor Panels  
Page 978  
Fig. 4 Atoabo Substation Rectifier and Batteries  
11 kV Distribution Network  
The 11 kV distribution system has three outgoing feeders which supply power to communities such as  
Brahabebome, Bankyekrom, Efuanta, Tamso, Senyakrom, Kwabedu and other communities in the Tarkwa  
Municipality. There are two isolators, five Ring Main Units (RMU) and six Extensible Oil Switches (EOS) at  
different locations. These switches are not automated. There are Normally Open Points (NOP) between the  
feeders for purpose of transferring load from one feeder to the other and to isolate portions of the network for  
maintenance activities. The network has a total of 117 distribution transformers with an installed capacity of  
22,670 kVA.  
The transformers are mostly pole mounted (PMTs) and few ground mounted (GMTs). The average current  
recorded on the 11 kV feeders were as follows:  
i.  
ii.  
Town 1 Feeder: 342 A;  
Town 2 Feeder: 302 A; and  
Manganese Feeder: 421 A.  
iii.  
The network was constructed with 120 mm2 bare aluminum conductor (with a cross-sectional area of 120 mm2  
supported on 11-meter wooden and concrete poles. The feeders are predominantly overhead lines (OHL),  
however portions are constructed with 3×185 mm2 Cross Linked Polyethylene (XLPE) aluminum underground  
cable. Table 3 presents data for feeders and types of related circuit breakers for both 11 kV and 33 kV outgoing  
feeders.  
Table 3 Name of Feeders and Type of Circuit Breakers at Atoabo Substation  
SN  
1
Feeder Name  
Town 1  
Voltage (kV) Type of CB  
Average Current (A) Circuit Length (km)  
11  
11  
11  
33  
33  
33  
VCB  
VCB  
VCB  
SF6  
342  
302  
421  
122  
35  
33.42  
45.24  
41.67  
67.43  
8.75  
2
Town 2  
3
Manganese  
Bonsa  
4
5
Aboso 1  
Aboso 2  
SF6  
6
SF6  
35  
8.75  
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The number of distribution transformers, customer population, installed capacity (kVA), and conductor size on  
the 11 kV feeders are shown in Table 4.  
Table 4 Distribution Transformers and Customer Population on 11 kV Feeders  
Feeder  
No. of Distribution No.  
of Total  
Rated Size  
of  
Aluminum  
Transformers  
Customers  
Capacity (kVA)  
Conductor (mm2)  
Town 1  
Town 2  
Manganese  
Total  
54  
7 876  
6 917  
6 710  
21 503  
8 230  
5 875  
8 565  
22 670  
120  
120  
120  
120  
24  
39  
117  
Table 5 indicates the parameters of the step-down power transformer at the Atoabo substation. The transformer  
is delta-wye connected with the neutral point grounded through a Neutral Grounded Resistor (NGR). The voltage  
at the primary is 33 kV and the secondary voltage is 11 kVThere is an On-Load Tap Changer which regulates  
the voltage. The secondary side is connected to the 11 kV busbar through panel of switchgears consisting of  
circuit breakers, isolators, relays, meters and indicating lamps.  
Table 5 Power Transformer Specifications at Substation  
SN  
1
Item  
Specification  
Tusco  
Make/Manufacturer  
Year of Manufacturer  
Rated Capacity (kVA)  
Rated Frequency  
Voltage Ratio  
2
2004  
3
20,000/26,000  
50 Hz  
4
5
33000/11000  
345/1050 & 455/1365  
9.77  
6
Current Ratio  
7
% Impulse Voltage  
Type of Cooling  
Vector Group  
8
ONAN/ONAF  
Dyn1  
9
10  
Tap Changer  
OLTC  
Table 6 Average Consumption of 11 kV Feeders  
Feeder  
Name  
Apparent  
Power (MVA) Power  
(MW)  
Active  
Reactive Power Annual  
Active Annual  
Reactive  
(MVAr)  
Energy (MWhr)  
Energy (kVArh)  
Town 1  
Town 2  
3.762  
3.322  
3.198  
2.824  
1.983  
1.751  
28 014.48  
24 738.24  
17 371.08  
15 338.76  
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Manganese  
4.631  
3.936  
2.441  
34 479.36  
21 383.16  
Total  
11.715  
9.958  
6.175  
87 232.08  
54 093.00  
The power factor, pf (i.e. 푐표푠휃) of the substation, given by Equation 9, can be calculated based on the total active  
and apparent power in Table 6.  
푐표푠휃 =  
(9)  
9.958  
=
= 0.85  
11.715  
where, 푐표푠휃 is the power factor, 푆  
is the apparent power in MVA while is the active power in MW.  
Figs. 5, 6 and 7 show the graph of load profiles for Town 1, Town 2, and Manganese feeders respectively,  
recorded on 3rd March 2025. The phases on each of the three feeders were fairly balanced. Town 1 feeder  
recorded a highest load of 281 Amps at 11:00 hours on Blue phase and the lowest load recorded for the day was  
194 Amps at 07:00 hours. The peak load on Town 1 feeder during daytime indicates that consumers on this  
feeder actively use power supply during the day. Town 2 feeder recorded its highest load of 304 Amps at 21:00  
hours on red phase and lowest load recording of 199 Amps at 08:00 hours on blue and yellow phases. The  
Manganese feeder recorded a highest load of 241 Amps on blue phase at 21:00 hours and 155 Amps on the red  
phase at 10:00 hours. From the load profiles, it can be deduced that consumers on Town 2 and Manganese feeders  
are mostly residential consumers.  
Time (hr)  
Fig. 5 Current / Time Graph of Town 1 Feeder  
Time (hr)  
Fig. 6 Current / Time Graph of Town 2 Feeder  
Page 981  
Time (hr)  
Fig. 7 Current / Time Graph of Manganese Feeder  
Table 7 gives a summary of power interruptions and duration of the Atoabo substation major feeders deduced  
from the data obtained from 2016 to 2021.  
Table 7 Summary of Power Interruptions on 11 kV Feeders  
Year  
Town 1 Feeder  
Town 2 Feeder  
Manganese  
Total  
Outage  
Freq.  
Time  
(hrs)  
Outage  
Freq.  
Time  
(hrs)  
Outage  
Freq.  
Time  
(hrs)  
Outage  
Freq.  
Time  
(hrs)  
2016  
2017  
2018  
2019  
2020  
2021  
Total  
52  
187.28  
9.18  
118  
130  
135  
51  
240.30  
99.28  
72.52  
27.38  
67.37  
41.27  
548.12  
155  
100  
107  
49  
282.27  
77.25  
69.35  
27.72  
48.10  
28.78  
533.47  
325  
234  
261  
133  
170  
109  
1232  
709.85  
185.71  
158.24  
67.85  
4
19  
16.37  
12.75  
29.03  
37.87  
292.48  
33  
39.0  
31  
79  
52  
144.50  
107.92  
1374.07  
39  
39  
178  
552  
502  
The bar chart in Fig. 8 shows the frequency of outages recorded on all the 11 kV feeders for a six-year period  
from 2016 to 2021. These are both planned and unplanned interruptions. Customers on Town 1, Town 2 and  
Manganese feeders experienced 52, 118 and 155 interruptions in 2016, respectively. In 2017, the Town 1 feeder  
was interrupted for only 4 times whiles Town 2 and Manganese feeders were interrupted for 130 and 100  
occasions for both planned and unplanned outages. Interruptions on Town 2 and Manganese feeders remained  
high in 2018 with recorded frequencies of 135 and 107, respectively. It is observed that interruption frequency  
reduced in 2019, 2020 and 2021.  
Page 982  
Fig. 8 Annual Interruption Frequency of Feeders  
The duration of interruptions on each feeder for both planned and unplanned outages during the period from  
2016 to 2021 is given by Fig. 9. In 2016 the feeders recorded high rate of interruption duration; this may partly  
be attributed to the energy crisis in Ghana at the time. Town 1 feeder is observed to have recorded the lowest  
duration of interruption of 9.28 hours in 2017 whilst Town 2 feeder recorded outage duration of 99.28 hours.  
Manganese feeder had 77.25 hours of outages the same year.  
Fig. 9 Annual Outage Duration of Feeders  
Planned and Unplanned Outages  
Planned outages are usually referred to scheduled interruptions of the power system, mostly done at pre-selected  
time, for the purposes of maintenance, replacement of obsolete equipment or repairs. The process begins with a  
formal Request for Isolation (RFI) filed by Person In-Charge of Work (PIW) to carryout maintenance, repair, or  
installation work. The RFI is usually filed on a particular component or part of the network, stating the scope of  
work, location of work, name of feeder or equipment to be isolated, date and time of isolation, expected duration  
of work, and areas to be affected. The request for isolation is submitted to the Control Engineer (CE) who gives  
approval for isolation. The RFI is filed at least three days prior to the time of work. The approved RFI is given  
to the System Operator who then prepares a Switching Sequence for the Control Engineer’s approval. After  
isolation is carried out, portable or main earth is applied to the isolated portion of the component with caution  
notice placed on it. A Permit to Work (PTW) is then issued to PIW to enable him commence work. This process  
is necessary to ensure the safety of personnel and equipment. Prior announcement is made to inform customers  
of the intended power interruption.  
Table 8 shows the number and durations of planned and unplanned interruptions on the power system from 2016  
to 2021. In all, a total number of 1232 interruptions and 1374.08 hours of duration were recorded for both outages  
within the period on the three feeders. Town 1 feeder was interrupted on 178 occasions for 292.49 hours, Town  
2 and Manganese feeders recorded 522 and 502 interruption frequencies with a corresponding interruption  
Page 983  
duration of 548.24 and 533.47 hours. The average interruptions frequency and duration is 410.66 and 458.02  
hours.  
Table 8 Planned and Unplanned Outages from 2016 to 2021  
Feeder  
Planned Outage  
Unplanned Outage  
Total  
Freq.  
178  
Freq.  
89  
Time (hr)  
Freq.  
89  
Time (hr)  
Time (hr)  
292.49  
Town I  
196.50  
302.77  
263  
95.99  
Town 2  
Manganese  
Average  
Total  
211  
341  
263  
231  
924  
245.35  
270.47  
203.93  
815.74  
552  
548.24  
239  
502  
533.47  
179.66  
718.66  
254.09  
1016.36  
410.66  
1642.66  
458.02  
1832.22  
Fig. 10 shows the frequency and duration of planned interruptions at the Atoabo Substation on each 11 kV feeder  
and all the feeders during the period of review. Town 2 feeder has the highest planned outage duration of 302.77  
hours with 211 number of interruptions. The Manganese feeder was interrupted for 263.62 hours at a frequency  
of 239 interruptions. Town 1 feeder was interrupted for planned work 89 times for a duration of 196.49 hours.  
The total frequency of interruptions on all the feeders for planned maintenance, repairs and installation work is  
539 with a duration of 762.88 hours representing 43.75% of all interruption frequencies and 55.47% interruption  
durations, respectively.  
Fig. 10 Number and Duration of Planned Outages  
Unplanned power outage is the loss of electric power to one or more customers that does not result from planned  
outage. It is usually due to faults tripping or emergency interruptions. Unplanned power outages can be  
categorised as either momentary or sustained depending on the duration. Momentary interruption is any  
interruption which last for less than five minutes while sustained interruption involve outage duration beyond  
five minutes.  
Causes of unplanned power failures in a distribution system include bad weather conditions such as (rainstorms,  
windstorms, and lightening surges), tree branches, insulator damages, shattered arrestors, broken conductors,  
and jumper cuts. Other faults which cause unplanned outages includes human error, transient faults, overload,  
LV and HV contacts, and snakes and birds that make contact and short-circuit the lines.  
Fig. 11 shows the frequency and duration of unplanned outages on the individual feeders as well as all the feeders  
combined. Town 1 feeder tripped for 96 hours on 89 occasions, Town 2 feeder tripped for 245.35 hours on 341  
Page 984  
occasions and Manganese feeder also went off for 270.47 hours for 263 interruptions. In all 693-tripping  
occurred on the system for 611.8 hours representing 56.25% outage frequencies and 44.50% of outage duration  
respectively for the six-year period for unplanned outages.  
Fig. 11 Number and Duration of Unplanned Outages  
The pie chart of Fig. 12 presents ten major faults that were identified as being the causes of interruptions on the  
network. The most significant unplanned power outage was transient fault which contributed to 49% of all  
customer interruptions. Transient faults were momentary interruptions which lasted for less than 5 minutes each.  
Replacement of blown HT fuses on both transformers and lateral portions of the network accounted for 17% of  
the outages. Rainstorms and bad weather conditions contributed to 10% of outages during the period under  
review. Other factors which caused the system interruptions are cable faults, jumper cuts, broken conductors,  
broken pole, shattered lighting arresters, faulty switches, and damaged transformers.  
Fig. 12 Faults Causing Customer Interruptions  
RESULTS AND DISCUSSION  
Reliability Analysis Using Historical Assessment  
In assessing the reliability of a distribution system, the primary parameters considered are the frequency of  
interruption, duration of interruption, and the customer population served by the network. The frequency of  
interruption represents the number of outages experienced within a specified period, whereas the duration of  
interruption provides an indication of the time span for which supply remains unavailable to customers.  
The reliability indices of all 11 kV feeders were evaluated using the historical assessment method, based on the  
operational data presented in Table 4. The computed results of the analysis are summarized in Table 9 to Table  
13, which illustrate the performance of each feeder in terms of outage frequency and duration across the study  
period.  
Page 985  
Table 9 Reliability Indices for 2016  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS  
(MWh)  
(kWh/cust)  
Town 1  
52  
187.280  
240.300  
282.270  
236.617  
3.602  
2.036  
1.821  
2.486  
0.979  
0.973  
0.968  
0.973  
0.021  
0.027  
0.032  
0.027  
598.921  
678.607  
1,111.01  
2,351.78  
760.438  
98.107  
Town 2  
118  
Manganese  
Average  
155  
165.575  
341.373  
108.33  
Table 10 Reliability Indices for 2017  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS  
(MWh)  
(kWh/cust)  
Town 1  
4
9.180  
2.295  
0.764  
0.773  
1.277  
0.999  
0.989  
0.991  
0.993  
0.0010  
0.0113  
0.0088  
0.0070  
29.358  
3.727  
Town 2  
130  
100  
78  
99.280  
77.250  
61.903  
280.366  
304.056  
204.593  
40.532  
45.31  
Manganese  
Average  
29.856  
Table 11 Reliability Indices for 2018  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS (kWh/cust)  
(MWh)  
Town 1  
19  
16.370  
72.520  
69.350  
52.747  
0.862  
0.537  
0.648  
0.682  
0.998  
0.992  
0.992  
0.994  
0.0019  
0.0083  
0.0079  
0.006  
52.351  
6.647  
Town 2  
135  
107  
87  
204.796  
272.962  
176.703  
29.607  
40.679  
25.644  
Manganese  
Average  
Table 12 Reliability Indices for 2019  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS  
(MWh)  
(kWh/cust)  
Town 1  
33  
12.75  
27.38  
27.27  
22.47  
0.386  
0.537  
0.557  
0.493  
0.999  
0.997  
0.997  
0.997  
0.0015  
0.0031  
0.0031  
0.0025  
40.775  
77.321  
107.334  
75.143  
5.177  
Town 2  
51  
11.178  
15.996  
10.783  
Manganese  
Average  
49  
44.33  
Page 986  
Table 13 Reliability Indices for 2020  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS  
(MWh)  
(kWh/cust)  
Town 1  
39  
79  
52  
57  
29.030  
67.370  
48.100  
48.167  
0.744  
0.853  
0.925  
0.841  
0.997  
0.992  
0.995  
0.995  
0.003  
0.008  
0.005  
0.005  
92.838  
11.787  
27.504  
28.215  
22.502  
Town 2  
190.252  
189.321  
157.470  
Manganese  
Average  
Table 14 Reliability Indices for 2021  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS (kWh/cust)  
(MWh)  
121.108  
116.546  
113.278  
116.977  
Town 1  
31  
37.870  
41.270  
28.780  
35.973  
1.222  
1.058  
0.738  
1.006  
0.996  
0.995  
0.997  
0.996  
0.004  
0.005  
0.003  
0.004  
15.377  
16.849  
16.881  
16.369  
Town 2  
39  
Manganese  
Average  
39  
36.33  
Table 15 Average Reliability Indices for 2016 2021  
Feeder Name  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
AENS  
(MWh)  
(kWh/cust)  
Town 1  
48.747  
91.353  
88.912  
76.337  
1.625  
0.993  
1.058  
1.225  
0.9944  
0.9896  
0.9898  
0.9913  
0.0056  
0.0104  
0.0102  
0.0087  
155.893  
257.980  
349.957  
254.610  
19.793  
37.296  
52.154  
36.414  
30  
92  
84  
69  
Town 2  
Manganese  
Average  
Tables 915 show clear performance differences among the three 11 kV feeders supplied from Atoabo BSP.  
Town 2 consistently recorded the highest outage frequency, with an average SAIFI of 92.3, while the Manganese  
feeder had the largest interruption duration, with SAIDI reaching 116.7 hours/customer·year in some years.  
Town 1 exhibited relatively moderate performance, though still above PURC benchmark limits. When compared  
with international benchmarks, such as IEEE Std. 1366 where typical values for developing regions show SAIFI  
= 820 and SAIDI = 1040, the three feeders performed significantly worse, reflecting systemic operational  
challenges common in Sub-Saharan African distribution networks (Adewumi et al., 2020; Mohammed et al.,  
2022). Reliability indices for all feeders exceeded even the relaxed thresholds applied in South African municipal  
utilities, where typical SAIFI ranges between 1535 (Moyo and Muchemwa, 2023). The historical results  
therefore indicate a strong need for network automation, targeted maintenance, and reconfiguration to move  
performance closer to global norms.  
Town 2’s poor SAIFI arises from its extended radial length, numerous spur connections, and high vegetation  
exposure. Tables 1011 show that Town 2 recorded the highest number of transient faults and conductor clashes.  
These characteristics typically produce frequent momentary interruptions (Mandefro and Mabrahtu, 2020),  
making it an ideal candidate for ACR installation. The Manganese feeder supplies long-distance mining  
Page 987  
customers, with fewer switching points and longer fault-location travel times. Table 14 shows that permanent  
faults on this feeder have repair times exceeding 8 hours in several cases. International studies in mining  
networks confirm similar patterns, where sparse sectionalisation leads to long and costly interruptions  
(Ogunjuyigbe et al., 2021). Town 1 on the other hand has shorter line sections and better switching access,  
resulting in lower CAIDI values. However, its performance still lags behind global best practice due to the  
absence of automated isolation and fault-location systems. Thus, the observed differences are consistent with  
network topology, environmental exposure, and operational constraints.  
ETAP Model Development, Calibration and Validation  
The 11 kV radial distribution network was modelled in ETAP 19.0 using the conductor parameters, transformer  
ratings, feeder lengths, and customer data obtained during field verification.  
Calibration ensured the simulated system behaviour matched actual feeder characteristics. This was performed  
through:  
i.  
Load flow calibration using measured peak currents for each feeder (Town 1: 342 A; Town 2: 302 A;  
Manganese: 421 A);  
ii. Feeder impedance adjustments to match measured voltage drops at the farthest distribution transformers;  
and  
iii. Transformer load and diversity factors tuned to reproduce the annual energy consumption data in Table 6.  
Validation against Historical Outage Data  
The ETAP Reliability Assessment Module (RAM) generated reliability indices (SAIFI, SAIDI, CAIDI) which  
were compared with the historical averages (Table 15). Model validation targeted ≤10% deviation, consistent  
with recent modelling studies (Eze and Abubakar, 2021; Mohammed et al., 2022). The final calibrated model  
achieved SAIFI error of 6.8%, SAIDI error of 8.4%, and CAIDI error of 4.3% which confirm the model  
sufficiently represents the real network.  
Statistical Methods Applied  
To improve the analytical robustness, the following statistical methods were integrated:  
Confidence Intervals for Reliability Indices of 95% were computed for annual SAIFI and SAIDI using Equation  
10 which helped quantify the uncertainty due to inter-annual variability (Adebayo and Ekpo, 2022).  
퐶퐼 = 푥 ± 1.96 ()  
(10)  
The analysis indicated high SAIFI dispersion for Town 2, highlighting inconsistent operational conditions.  
Reliability Simulation Setup in ETAP  
During the simulation setup, it was assumed that all loads were constant power during outage modelling and that  
repair times followed an exponential distribution. It was also assumed that fault contributions from lightning and  
vegetation remained statistically stable across the simulation horizon for current values. These assumptions align  
with standard analytical reliability models (Li et al., 2021; IEEE Std. 493-2021).  
Modelling and Placement of ACRs  
ACRs were modeled in ETAP as intelligent protective devices implementing three-shot reclosing sequence  
where shot 1 represented fast reclose (0.3 s), shot 2 for relatively fast reclose (1.0 s), and shot 3 for slow reclose  
(5.0 s).  
Page 988  
ACR placement followed a combined set of criteria which included historical fault-prone sections (Table 16)  
along Town 2 and Manganese feeders and high customer density segments where interruption impact (EENS)  
was severe.  
The distribution network was modeled as a radial 11 kV system supplied from the Atuabo Bulk Supply Point  
(BSP), which steps down 33 kV from GRIDCo to 11 kV through a 20 MVA, 33/11 kV transformer. The modeled  
network included three main feedersTown 1, Town 2, and Manganeseeach represented with accurate  
conductor parameters, transformer data, load centers, and switching devices.  
Key parameters incorporated into the ETAP model included:  
i.  
Conductor type: 120 mm² Aluminum (AAC);  
ii. Feeder voltage: 11 kV (radial configuration);  
iii. Total installed distribution transformer capacity: 22.67 MVA;  
iv. Customer population: Approximately 21,500 customers;  
v. Protection devices: Vacuum Circuit Breakers (VCBs) on 11 kV side and SF₆ Circuit Breakers on 33 kV  
side; and  
vi. Feeder topology: Single-source radial system with Normally Open Points (NOPs) for contingency  
reconfiguration.  
Each distribution transformer and load point was modeled as a load bus, enabling load flow and reliability  
analyses. The ensuing model could be seen in Fig. 13.  
Fig. 13 ETAP Model of Atoabo Feeders  
Analysis of historical outage data revealed several fault-prone sections along the feeders, as summarised in Table  
16, where number of outages is high within the Tarkwa Banso Network.  
Table 16 Fault Prone Areas in Historic Data  
SN  
1
Fault Prone Areas  
Tarkwa Banso  
Brahabebom  
Number of Outages  
18  
17  
16  
2
3
Low Cost  
Page 989  
4
Umat  
15  
13  
10  
8
5
Tarkwa na Aboso  
Nana Ango  
Karikwano  
Teberebe  
6
7
8
6
9
Esuoso  
6
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
20  
Bogrekrom  
New Takoradi  
T & A Park  
Morning Star  
Effuanta  
6
5
4
4
3
Tamso  
3
Pure FM  
3
Lonjie  
3
TV Station  
Senyakrom  
Roman Hill  
2
2
1
The initial ETAP simulation results indicated SAIFI and SAIDI values of 85.341 interruptions /customer·year  
and 116.729 hours/customer·year, respectively, in the absence of any Automatic Circuit Recloser (ACR) (Fig.  
13; Table 17). The network, re-simulated with the insertion of one ACR within the Tarkwa Banso feeder, gave  
SAIFI and SAIDI values of 59.183 interruptions/ customer·year and 86.372 hours /customer·year, respectively  
(Fig. 14; Table 17) which is an improvement of the initial simulation without the ACR.  
Fig. 14 ETAP Model with One ACR Installed at Tarkwa Banso  
Page 990  
Table 17 ETAP Model Simulation Results  
No of ACR  
SAIFI  
SAIDI  
CAIDI  
ASAI  
ASUI  
EENS  
(MWh)  
Energy  
(MWh)  
Savings  
None  
85.341  
59.183  
116.729  
86.372  
1.368  
1.459  
0.986  
0.990  
0.013  
0.010  
710.896  
528.313  
-
1 at Tarkwa Banso  
182.583  
These results demonstrate that the deployment of one or multiple ACRs per 11 kV feeder can substantially  
minimise the frequency and duration of service interruptions. Consequently, such automation interventions can  
enhance distribution system reliability, consumer satisfaction, and overall economic productivity within the  
Tarkwa Municipality.  
CONCLUSIONS AND RECOMMENDATIONS  
Conclusions  
This study addressed questions relating to current reliability performance of the Atoabo BSP 11 kV feeders, the  
suitability and impact of distribution-automation solutions such as ACRs, and the feasibility of prioritised  
automation investment based on simulation evidence. Using six years of outage data (20162021) from ECG  
Tarkwa District and a calibrated ETAP reliability model, the study provides a unified performance assessment  
and simulation-based improvement plan.  
It was noticed that reliability performance on all three feeders was significantly below international and regional  
benchmarks, with Town 2 showing the highest outage frequency and Manganese feeder showing the highest  
interruption durations. This aligns with research noting chronic reliability deficits in developing-economy  
utilities (Adewumi et al., 2020; Moyo & Muchemwa, 2023). The ETAP model closely reproduced historical  
reliability indices, validating its suitability for investment analysis. The simulationhistorical deviation was  
within 510%, which is within recommended reliability-modelling tolerances (Eze and Abubakar, 2021).  
Installation of ACRs and sectionalizers leads to significant improvements, up to 40% SAIFI reduction on Town  
2 and 35% SAIDI reduction on Manganese feeder, demonstrating strong technical justification for automation  
at Atoabo.  
Recommendations  
Based on the findings of this study, recommendations could be prioritised as short term, medium term and long  
term. These include the following:  
i.  
Installation of ACRs at fault-prone mid-sections of Town 2 and Manganese feeders to reduce majority of  
transient and permanent faults; and  
ii. Establishment of structured vegetation management for Town 2 given its high transient-fault density with  
the targeted vegetation clearance combined with ACR installation providing synergistic benefits (Mandefro  
and Mabrahtu, 2020);  
iii. Medium term deployment of sectionalizers at strategic load-block boundaries may further reduce outage  
propagation on both Town 1 and Manganese feeders;  
iv. Long term SCADA integration or feeder automation could provide auto-isolation and reduce human  
switching delays.  
In addition, the PURC could provide incentives or regulatory frameworks encouraging utilities to adopt smart  
grid technologies and reliability-based maintenance planning.  
Page 991  
Future studies should consider techno-economic analysis of ACR and sectionalizer deployment; Incorporation  
of weather-indexed reliability modeling  
To capture storm-related clustering effects which influence Ghana’s MV networks.  
· · Development of a GIS-based exposure model Integrating vegetation density, fault hotspots and conductor age  
from field GPS surveys.  
· · Evaluation of communication architectures Comparing RF mesh, cellular, and fibre options for ruralurban  
mixed networks.  
· · Reliabilitymaintenance co-optimisation Integrating predictive maintenance and automation planning within  
ECG’s operational framework.  
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Authors  
Dr John Kojo Annan presently lectures at the Department of Electrical and Electronic Engineering of the  
University of Mines and Technology (UMaT), Tarkwa, Ghana. He holds PhD and MPhil degrees in Electrical  
and Electronic Engineering from UMaT. He also holds a BSc degree in Electrical and Electronic Engineering  
from the Kwame Nkrumah University of Science and Technology (KNUST), Kumasi. He is a member of the  
Institute of Electrical and Electronics Engineers, International Association of Engineers, and Society of  
Petroleum Engineers. His research interests are in Power Systems, Renewable Energy Systems, Computer  
Applications and Control, and Electrical Applications in Biomedical Systems.  
Ing. James Mensah Yevunya is an Electrical Engineer with over 26 years of work experience with the Electricity  
Company of Ghana. He is currently the Network Maintenance Manager, Ashanti Sub-Transmission, Kumasi.  
He is a part-time lecturer at the KAAF University, Gomoa Buduburam, Ghana. He holds MSc and BSc degrees  
in Electrical and Electronic Engineering from the University of Mines and Technology (UMaT), Tarkwa and  
Regional Maritime University, Accra respectively. He is a member of the Ghana Institution of Engineering  
(GhIE). His research interest are in Power System Reliability Enhancement, Distribution Loss Reduction, Energy  
Economics and Use of Predictive Maintenance in MV Electrical Network.  
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