23.anderson go - non-conventional

7/30/2019 23.Anderson GO - Non-Conventional

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NON-CONVENTIONAL SUBSTATION AND DISTRIBUTION SYSTEM FOR

RURAL ELECTRIFICATION

G. O. Anderson and K. YanevElectrical Engineering Department, University of Botswana

ABSTRACT

In rural areas the concentration of users of electrical

energy is low, and costs related to the deployment of a

conventional substation are prohibitive. As a result, in

many cases, a power utility will not be able to generate

an adequate return on the investment necessary to

bring a conventional distribution substation on line.

On the other hand, rural users are typically satisfied

with a lower quality service and are willing to suffer

some power outages if this means having access to

electric power at a reasonable price. Additionally, highvoltage transmission lines on their path from power

source to major urban centres typically transverse

many rural areas to which they do not supply

electricity. In order to address the drawbacks

associated with prohibitive costs of a conventional

substation, a relatively small non-conventional

substation which can be located close to or underneath

extra high voltage transmission lines is investigated.

These non-conventional substations tap directly into

the overhead transmission lines using tapping through

high voltage connectors and do not interrupt the flow

of power along the transmission line. A combination of Non-conventional substation and a single wire earth

return (SWER) could provide a cheaper application to

rural electrification. The cost effective nature of the

combination for rural electrification is investigated

and analysed.

KEY WORDS Non-conventional Substation, Distribution System, RuralElectrification

1. INTRODUCTION

1.1 ALTERNATE SOURCES OF POWER SUPPLYFOR RURAL ELECTRIFICATION

The consumption of primary sources of energy by sourcein Botswana is similar to those of other third worldcountries. Alternate sources of power supply can becategorized as follows:

• Grid electricity (mains)

• Solar power

• Wind Power

• Diesel Generators

• Tapping from High Voltage Lines

• Single wire earth return

Bullets 1,5 and 6 are considered in this paper.

1.1.1 GRID ELECTRICITY SUPPLY

In rural areas the concentration of users is low and costsrelated to deploying a conventional substation are prohibitive. As a result, in many cases a power utility willnot be able to generate an adequate return on the largeinvestment necessary to bring a conventional distributionsubstation on line. On the other hand, rural users are

typically satisfied with a lower quality of service and arewilling to suffer some power outages if this means theywill have access to electrical power at a reasonable price

[2]. Additionally, high voltage transmission lines ontheir path from power source to major urban centrestypically traverse many rural areas to which they do not

supply electricity. Distribution networks are connected tothe transmission portion of the system via transmission

lines and substations [3].

1.1.2 Non Conventional Substation

In order to address the drawbacks associated with prohibitive costs of a conventional substation, a relativelysmall non conventional substation which can be locatedclose to or underneath extra high voltage transmissionlines is investigated. These non-conventional substationstap directly into the over head transmission lines using

tapping through high voltage connectors [4,6].

1.1.3 Single Wire Earth Return (SWER)

SWER can help reduce the amount of capital expenditure

required when compared to the usual three phase power supply of grid electricity. The application of SWER isdependent on the distance from source of power to pointof connection for application, because voltage drop alongthe wire depends on the distance.

The research focuses on non-conventional substation and

single wire earth return distribution system with respect torural electrification. Solar technology application anddiesel plant use are available in rural areas of Botswana.Wind power is not applicable, because the wind speed istoo low for power generation.

2. RURAL LOAD

To electrify a rural area, it is necessary to estimate the possible loads in the area. Loads in the rural areas areclassified into three categories: household load, small

business load and rural telecoms network loads for service providers.

• Household load is approximately506W• Business Load is approximately 1046W

• Base Transceiver Station (BTS) for Cellular 1346W



3. NON-CONVENTIONAL SUBSTATION

The connections of the non-conventional substation are asindicated in section 1.1.2, and [4,6]. Figures 3.1 and 3.2show how the non conventional substation taps power

from a high voltage transmission line.

One drawback of the above non-conventional substationsis that they do not provide any redundancy in the case of

failure of one of the components of the substation or overload. But this draw back is not a serious concern for people in the rural remote villages of Botswana. Nonconventional substations can be implemented where thereare high voltage lines passing through the village only or

where the HV line passes not more than 60 km away from

the village to avoid voltage drop problems.

Figure 3.1: Non conventional substation tapping power between two steel towers [52]

Figure 3.2: non conventional substation tapping power across a steel tower



3.1. NON CONVENTIONAL SUBSTATION

MODEL, DESIGN AND OPERATION

Non conventional substations use capacitive dividers totap power from high voltage lines for the purpose of meeting the electric power needs of rural and remote

areas. The principles of capacitive – couplingtransformers are not new, as they have long been used

both by manufacturers of the capacitor voltagetransformers required by electrical utilities and by someutilities for feeding small loads [5]. Figure 3.3 shows thecircuit model of a capacitive substation and figure 3.4shows the Thevenin equivalent circuit of the voltagedivider (C1 and C2) seen from the load side. The Thevenin

equivalent voltage divider thV is given by:

inth V C C

C V ×

+=

21

1 3.1

The impedance is given by capacitors in parallel as shown

in figure 3.3 i.e.21 C C C th += . The FSC block in figure

3.3 represents the Ferro resonance suppression (FSC)circuit.

This circuit is important since Ferro resonance and over voltage transients problems can occur in this substationduring different conditions. The FSC comprises a

capacitor 3C , an inductor 1 L connected in parallel and a

damping resistor R connected in series as shown on

figure 3.3. Values of capacitor 3C and inductance 1 L are

calculated so that

[ ] 12

2=

LC f π , where

f is frequency

of power signal [5]. The value of R is calculated so that

C L /3C

L R ⎟

⎠

⎞⎜⎝

⎛ <<

3

2, whereby dampening of

resonance is obtained [6].Tr is the fixed turn ratiodistribution transformer and is connected to the AC loadsvia the FSC.

Figure 3.3: Capacitive divider substation

Figure 3.4: Thevenin’s equivalent circuit of the voltage divider

The inductor L in figure 3.4 is added in series to thecapacitive voltage divider to provide reactance that

cancels the Thevenin reactance thC at 50 Hz. The

regulation is done by adjusting 1C , 2C and L so they

satisfy the equation below:

12 = LCw 3.2

Where 502π =w rad/seconds

Since the impedance is zero at 50 Hz, the output voltage

2V remains equal and in phase with ( thV ), which in turn

is proportional to and in phase with inV where the load

can be resistive, capacitive or inductive.

When the capacitive – coupling technique is used as asubstation feeding remote loads or for ruralelectrification, it normally includes distribution

transformers installed on the outgoing feeders [4]. Theother methods of capacitive divider which do not connect

directly to the HV line use the shield wire. The shieldwire runs horizontally to the phase conductors of a highvoltage transmission line and terminates to ground at agiven substation. In this particular application the shield

wire runs from the steel tower insulator to the substationwhere it terminates to ground. One of these methods wasfirst studied by Leigh Stubbs of South Africa and isreferred to as the Isolated shield wire – passive method. This technology is cost effective when compared withmore conventional electromagnetic coupling systems, e.g.

high voltage power transformers [7]. In Botswana nonconventional substations have never been tried. Thecapacitive voltage divider substation has never been used

by Botswana Power Corporation (BPC) for ruralelectrification.

3.2 SINGLE WIRE EARTH RETURN SYSTEM

Single Wire Earth Return (SWER) is a single-wiretransmission line for supplying single-phase electrical power to rural sparsely populated areas. SWER systemsare mainly used in rural electrification but can also beused in larger isolated loads such as water pumping.

3.2.1 SWER System Description

The system is as shown on figure 3.5



Figure 3.5: SWER system diagram

The SWER system has the following major components:

isolator transformer, distribution line, distributiontransformer and earth system. The villages which useSWER system must have soil resistivities that are suitablefor SWER system earthing. SWER technology has been

applied in many countries and all specifications areknown.

4. CASE STUDY

The costs of using conventional and non conventionalsubstations for tapping power from high voltagetransmission lines was evaluated using the villages of Hatsalatladi and Boatlaname. The costs of Single Wire

Earth Return system versus three phase systems were alsoevaluated using the same rural villages.

The rural villages of Hatsalatladi and Boatlaname were

chosen because of the following reasons:• High Volltage transmission lines traverse

these villages

• The two villages are not electrified

Loadflow studies were carried out to determine the ability

of the system components to transfer energy fromgeneration sources to load without overloading the power components.

4.1 CASE STUDY: TAPPING POWER FROM HIGH

VOLTAGE TRANSMISSION LINES

Cost implications of building conventional and non – conventional 66/11 KV substations between the ruralvillages of Boatlaname and Hatsalatladi wereinvestigated. The villages of Boatlaname and Hatsalatladiare located in the Kweneng district and are approximately60 km apart. A line of 66 KV passes through these

villages but they are not electrified. These villages, eachhas a primary school, kgotla, clinic, bar, shop and someresidential houses. The substation proposed is located between the two villages with two 11 KV feeders, one for each village.

Case 1

4.1.1 Design of Non conventional substation atHatsalatladi and Boatlaname

The non conventional substation is relatively small in

terms of size and can be close to or underneath extra highvoltage transmission lines. A single line diagram of a nonconventional substation is shown on figures 4.1. Since thedistribution substation is used to distribute power to two

villages, a bus bar and tie bar shall be used with theassociated autoreclosers and knife links. Data for the

different system components was collected fromBotswana Power Corporation. All the prices for differentsystem components were collected from localmanufacturers and suppliers. At these villages the HV line

present is 66KV

Capacitors are chosen as follows C 1 = 0.98 µF, C 2 = 1.62µF, L =? Capacitors are chosen in such a way that C 1 is

smaller than C 2 by a factor that can give the desiredvoltage level at the output.

Therefore the Thevenin equivalent voltage divider Vth isgiven by:

inth V C C

C V ⎥

⎦

⎤⎢⎣

⎡

+=

21

1= kv66

62.198.0

98.0⎥⎦

⎤⎢⎣

⎡

+ 4.1

= 24.88kv ≈ 25kvAnd the series inductance L is given by:

2

1

Cw L = , where w = 2π50 rad/sec

C = C1 + C2

= 0.98 + 1.62= 2.6 µF

Therefore( )26 502106.2

1

π ××=

− L = 3.897 H

For designing the desired ferroresonance suppressioncircuit (FSC) the following points are considered:The capacitor C 3 is connected in parallel to the inductor

L1 and both are connected in series with a dampingresistor Rd

C f = C 1 + C 2= 0.98 +1.62 =2.6µF

And( )

f

f C f

L2

2

1

π

≤

Therefore, H L f 897.3≤ The damping resistor Rd should be in the range of thesystem rated load.



Figure 4.1: Non – Conventional 66 / 11 KV Substation single line diagram

Case 2

4.1.2 Design of Conventional substation at

Hatsalatladi and Boatlaname

The conventional substation is a fully flashed substationthat terminates the transmission line and as a result

maintains a high level of service. A single line diagram of the conventional substation is shown in figure 4.2.

The conventional substation has got back-up such that

when one component of the substation fails the customer still gets power via other system components. The cost breakdown covers planning, designing and installation.

Figure 4.2: 66 / 11 KV conventional substation single line diagram.



4.1.3 Design of a Power Distribution System at

Hatsalatladi and Boatlaname

A case study was conducted at the rural villages of

Hatsalatladi and Boatlaname to determine the percentagesaving when using SWER system. A potential load wasestimated and the system was modelled using DigSilentsoftware to determine the system’s capability to transfer energy from the source to the load without overloading

transmission lines and other power system components.The life cycle cost of a SWER and a three phase systemwere evaluated. The following circuit components weremodelled using DigSilent power factory software. Figure4.3 represents a three phase system while figure 4.4

represents a SWER system for the villages of Hatsalatladi

and Boatlaname.

Figure 4.3 Design of a single-line diagram of a three-phase system for the villages of Hatsalatladi and Boatlaname.

Figure 4.4: Single line diagram for SWER system.



4.1.4 Design of a three phase system for Boatlaname

and Hatsalatladi

The single wire earth return (SWER) uses the 66/19.1 KVtransformer. And when power is reticulated in the villagessingle phase pole mounted transformers are used to step

down the voltage from 19.1 KV to 240 V.

4.2 LIFE CYCLE COSTING OF ENERGY

SYSTEMS

Doing a life-cycle cost analysis (LCC) gives the total costof the power system - including all expenses incurredover the life of the system. There are two reasons for carrying out a LCC analysis: 1) to compare different power options and 2) to determine the most cost-effective

system designs. The LCC analysis consists of finding the present worth of any expense expected to occur over thereasonable life of the system [11]. To be included in theLCC analysis, any item must be assigned a cost, eventhough there are considerations to which a monetary valueis not easily attached. A meaningful LCC comparison can

only be made if each system can perform the same work with the same reliability.

4.3 LCC CALCULATION

The life-cycle cost of a project can be calculated using theformula:

LCC = C + Mpw + E pw + R pw - S pw.[98] 4.7

Where the pw subscript indicates the present worth of each factor.

The capital cost (C) of a project includes the initial capitalexpense for equipment, the system design, engineering,and installation. This cost is always considered as a single

payment occurring in the initial year of the project,regardless of how the project is financed.

Maintenance (M) is the sum of all yearly scheduledoperation and maintenance (O&M) costs. O&M costsinclude such items as an operator's salary, inspections,insurance, property tax, and all scheduled maintenance.

The energy cost (E) of a system is the sum of the yearlyfuel cost if applicable. Energy cost is calculatedseparately from operation and maintenance costs, so thatdifferential fuel inflation rates may be used.

Replacement cost (R) is the sum of all repair andequipment replacement cost anticipated over the life of

the system. Normally, these costs occur in specific yearsand the entire cost is included in those years.

The salvage value (S) of a system is its net worth in thefinal year of the life-cycle period. It is common practiceto assign a salvage value of 20 percent of original cost for mechanical equipment that can be moved. This rate can

be modified depending on other factors such asobsolescence and condition of equipment.

Future sums of money must also be discounted because of the inherent risk of future events not occurring as planned. Several factors should be considered when the

period for an LCC analysis is chosen Comparison canonly be made if each system can perform the same work

with the same reliability.

5. RESULTS AND ANALYSIS OF GRID POWER

SOURCES

The villages of Hatsalatladi and Boatlaname were used asa case study. The life cycle costs of conventional and nonconventional methods of tapping power from high voltage

transmission lines and electrical power distribution usingthree phase and SWER systems are presented. The results

also cover DigSilent simulation for power distribution

using SWER and three phase systems. Load flow analysiswas carried out on a conventional substation, SWER andthree phase systems. Simulation results for conventionalsubstation are also presented.

5.1 RESULTS FOR CONVENTIONAL AND NON

CONVENTIONAL SUBSTATIONS

Load flow results of a conventional substation are shownin fig 5.1. Project life cycle costs for a conventionalsubstation are shown table 5.1. Load flow studies arecarried out to determine the active and reactive flows inthe lines, the voltage profiles at the buses and systemlosses. Lifecycle costs for non conventional substation are

shown on table 5.2.

The power system components are based on the proposeddesign from figure 4.2. The prices for differentcomponents were obtained from local manufacturers andsuppliers.



Table 5.1: Life cycle costs for a fully flashed conventional substation with redundancy

Item Item description QTY Unit cost

(BWP)

Total cost (

BWP )

Percent

Total

1 CAPITAL COSTS ( C )

66 kv disconnector switch - motorised 3 30,000 90,000

66 kv breaker 3 125,000 375,000

66 kv busbar 1 160,000 160,000

11 kv autorecloser 3 164,000 492,000

On load 11 kv isolators 3 22,500 67,500

Knife-links 2 5,800 11,600

11 KV busbar 1 10,000 10,000

11 kv tiebar 1 10,000 10,000

Civil works 1 400,000 400,000

earthing 1 175,000 175,000

66/11 kv, 5 MVA Transformer 2 4900,000 9,800,000

A) SUBTOTAL 11,591,100 80

2 OPERATION & MAINTENANCE ( Mpw )

Servicing of Transformer and switchgear 2 1,500,000 3,000,000

B) SUBTOTAL 3,000,000 21

3 REPLACEMENT (Rpw) (YEAR)

On load 11kv isolators ( 20 ) 3 22,500 67,500

66 KV breaker ( 20 ) 3 125,000 375,000

C) SUBTOTAL 442,500 3

4 SALVAGE (Spw) ( YEAR )

20% of original (20)

D) SUBTOTAL 695,466 4.8

TOTAL LIFE – CYCLE COSTS (C+Mpw+Rpw-Spw) 14,338,134 100

Table 5.2: Life cycle cost for a non conventional substation (capacitor divider substation)Item Item Description Qty Unit cost

(BWP)

Total cost (

BWP )

Percent

Total


66 kv disconnector switch - motorised 1 30,000 30,000

66 kv breaker 1 125,000 125,000

11 KV busbar 1 10,000 10,000

11 kv autorecloser 3 164,000 492,000

On load 11 kv isolators 1 22,500 22,500

Knife-links 2 5,800 11,600

11 kv tiebar 1 10,000 10,000

Civil works 1 400,000 400,000

earthing 1 175,000 175,000

25/11 kv, 250 KVA Transformer 1 2900,000 2,900,000Capacitors C1 and C2 1 15,000 15,000

Inductor L 1 8,000 8,000

FSC 1 12,500 12,500

SUBTOTAL 4,176,100 75

2 OPERATION AND MAINTENANCE (Mpw)

Servicing of Transformer and switchgear

1 1,500,000 1,500,000

SUBTOTAL 1,500,000 27


On load 11kv isolators ( 20 ) 1 22,500 22,500

66 KV breaker ( 20 ) 1 125,000 125,000

C) SUBTOTAL 147,500 2.6

4 SALVAGE (Spw) ( YEAR )


D) SUBTOTAL 250,566 4.5TOTAL LIFE – CYCLE COSTS ( C+Mpw+Rpw-Spw) 5,573,034 100



Figure 5.1: load flow results for three phase system for Boatlaname and Hatsalatladi

5.1.1 Discussion

It is noticed that when a non conventional substation isused the cost of construction is substantially reduced. Thisis attributed to the absence of back up in the nonconventional substation and only one transformer is

required for a non conventional substation. The absenceof 66 KV bus bar interconnecting the two transformersalso reduce the cost significantly.

Therefore non conventional substations can be used to provide robust power source in the rural areas of

Botswana and enhance rural telecommunications as theyare cost effective. The cost savings from the above casestudy is (14,338,134 – 5,573,034 = BWP 8,765,100). These substations are only applicable where there areextra HV or HV power lines traversing rural villages.

5.1.2 Results for Three Phase and SWER Systems.

Figure 5.1 shows load flow results for three phase systemwhile figure 5.2 shows load flow results for SWER

system. Life cycle costs for three phase system and

SWER system are shown on tables 5.3 and 5.4respectively.

The results from figure 5.2.show that voltage magnitudes,voltage phase angles and equipment setting are operating

within their limit for a given load profile.



Table 5.3: Life cycle cost for three phase system (prices obtained from local suppliers)

Item Item Description Qty Unt Cost (BWP) Total Cost

(BWP)

Percent

Total

1 CAPITAL COST (C)

Three Phase Power lines + Neutral line (80km) 4x80 8,000 2,560,000

66 kV disconnector switch - motorised 1 30,000 30,000

66 kV breaker 11 kV busbar

11

125,00010,000

125,00010,000

11kV autorecloser 3 164,000 492,000

On-load 11 kV isolator 1 22,500 22,500

Knife –links

11 kV tiebar

2

1

5,800

10,000

11,600

10,000

Civil works 1 400,000 400,000

Earthing 1 175,000 175,000

66/11kV, 400 kVA Transformer 1 2,900,000 2,900,000

A) SUBTOTAL 6,736,100 82.8


Servicing of Transformer and Switchgear 1 1,500,000 1,500,000

B) SUBTOTAL 1,500,000 18.4


On load 11 kV isolators (20) 1 22,500 22,500

66 kV breaker (20) 1 125,000 125,000

C) SUBTOTAL 147,500 1.8

4 SALVAGE (Spw) (YEAR)


(D) SUBTOTAL 250,566 3.1

TOTAL LIFE CYCLE COSTS (C + Mpw + Rpw –Spw) 8,133,034 100

Figure 5.2: load flow results for SWER system



Table 5.4: Life cycle costs for SWER system (prices obtained from local suppliers)Item Item Description Qty Unit cost

(BWP)

Total cost (

BWP )

Percent

Total


SWER line (long span using Magpie Conductor) 80km 12,000 960,000

Isolating Transformer:

Fuse links

400KVA transformer Earthing

Reclosers

Sectionalisers

Distribution transformers:10KVA transformers

Earthing

2

11

1

5

104

104

14,000

85,00014,000

28,000

8,000

7,500

4,000

28,000

85,000

14,00028,000

40,000

780,000

416,000

A) SUBTOTAL 2,351,000 82


Servicing of Transformer and switchgear

1 500,000 500,000

B) SUBTOTAL 500,000 17.5


Fuse links ( 20 ) 1 14,000 14,000

Sectionalisers ( 20 ) 8 8,000 64,000

C) SUBTOTAL 147,500 5

4 SALVAGE (Spw) ( YEAR )20% of original (20)

D) SUBTOTAL 141,060 4.9

TOTAL LIFE – CYCLE COSTS ( C+Mpw+Rpw-Spw ) 2,857,440 100

5.1.3 Discussion

From figures 5.1 and 5.2 it can be seen that all the buses

are operating within their voltage limit. And also the phase angles are within tolerance for all the buses utilised

in this load flow analysis. The use of SWER system as arobust power source is viable in the rural areas of Botswana. The simulations show that SWER system can

provide enough power to the rural areas as three phasesystem. But the life cycle costs suggest that by using aSWER system power utilities and corporations can save

cost by almost 50% as can be seen in table 5.4.

6. CONCLUSION

In most of the rural areas of Botswana power sources arenot always available and this scenario has led to rural

dwellers in these areas being unable to accesstelecommunication and other electrical services. Thisresearch investigated different power sources for application in the rural areas of Botswana taking into

consideration the life cycle costs and the technologyefficiency of each power source.

High Voltage tapping is an emerging technology usingnon conventional methods e.g. (capacitor divider substation) for rural electrification. A capacitive voltagedivider substation was designed to service the ruralvillages of Hatsalatladi and Boatlaname. Another substation was designed using conventional methods for

the same villages and the life cycle costs of the twosubstations show that capacitive voltage divider substation is cheaper as indicated in table 6.1.

The life cycle costs conducted on the designed systemsshow that SWER system is more cost effective as

indicated in table 6.1. Therefore SWER system is a good

option for electrification of rural settlements, becauseonce implemented, it can cater for everyone in the villageincluding service providers and customers alike. The

price for individual connections will also be affordable asits life cycle costs are low when compared with three

phase system.

The life cycle costs for different power source alternatives

investigated are shown in table 6.1.

Table 6.1: life cycle cost for different preferred power sourcesPower source Type of technology Life cycle cost

(BWP)

Grid

Capacitor divider

substation

5,573,034

HV tapping

Conventional

substation

14,338,134

SWER 2,857,440Power distribution

Three phase

distribution

8,133,034

Where HV transmission lines traverse rural villages or

pass nearby, non conventional substations (Capacitor voltage divider substation) should be used to tap power

and a SWER system can be used to reticulate power insuch villages. Where there is no grid, PV systems could be considered as a reliable load alternate power source.

7. REFERENCES:

[1] Sarah E.A. Kabaija, sources of energy used in householdsin Botswana

[2] Anthony J. Pansini.: Guide to Electrical Power

Distribution Systems. Marcel Dekker/CRC Press, BocaRaton, FL, 6th edition, 2005

[3] Transmission & Distribution World, April 2001



[4] Ferracci, P.: Ferroresonance, Groupe Schneider: Cahier technique no. 190:www.schneiderelectric.com/en/pdf//ect190.pdf , pp. 1-28,

March 1998.

[5] Gish, W.B., Feero, W.E., and Greuel, S.,:Ferroresonance

and loading relationships for DSG installations, IEEE

Trans. On Power Delivery, Vol. 6, No.2, pp. 736-743,April 1991.

[6] Bolduc, L., Bouchard, b., and beaulieu, G.: Capacitor

divider substation, IEEE Trans. Power Delivery, Vol. 12 No. 3, pp. 1202-1209, July 1997.

[7] CSA Standard CAN3-C13.1-M79, Capacitor Voltage

Transformers, March 1979.

[8] DIgSILENT Power Factory Software: Software for the

simulation of power system dynamics, DigSilent GmbH:

http://www.digsilent.de/software/

[9] P. Wolfs, S. Senini, D Seyoun and A, Loveday: AProposal to Investigate the Problems of Three-Phase

Distribution Feeders Suppling Power to SWER Systems,AUPEC 2004 Proceedings, September 2004.

[10] R. Billinton and R.N. Allan: Reliability evaluation of SWER

power systems, Plenum Press, New York,1996.

[11] Environmental and Ecological Life Cycle Inventories.

ECLIPSE public results.http://www.eclipse-eu.org/pubres_guide.html .

Principal Author: Professor George O. Anderson is theFounding Dean of the

Faculty of Engineeringand Technology of the

University of Botswana,Immediate-Past Head of the Department of Electrical Engineering,Associate Editor of theInternational Journal of

Power and Energy Systems, Interim Chairman of theBotswana Section of the IEEE and Resource Person for evaluation of Research Projects in Power and EnergySystems for funding by the South African NationalResearch Foundation (NRF). Professor Anderson has

written two books and has to his credit more than hundred publications in international journals and internationalconference proceedings. Prof. Anderson's researchinterests are in the areas of Power System Stability, Power Systems Economics Power Quality and RenewableEnergy.

Co-Author: Kamen M. Yanev holds a M.Sc. degree inElectrical and Control Engineeringfrom the HIMEE, Sofia. He has been a University Lecturer since1974, teaching in different

Commonwealth Universities around

the world. At present he is a Senior Lecturer in Control andInstrumentation Engineering at theUniversity of Botswana. He hasmore than 75 publications in the

area of Control Engineering,Electronics and Instrumentation.

Presenter: Professor George O. Anderson

23.anderson go - non-conventional

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