Current Network Condition

1
Current Network Condition

• Characterised by aged, under designed and
  technically obsolete infrastructure
• Old-fashioned oil insulated switchgear
  unreliable tripping times
• Inadequate (sometimes embarrassingly primitive)
  monitoring and protection systems
• Result - High number of outages
• Plant maximum life cycle exceeded
• SHER non-compliant
• No system integration

2

• Initiatives to Reduce Outages

• Network Master Plan
• Eskom (PTM) Engineering Studies
• Detail Audits by OEMs
• Rotek Engineering
• Siemens
• ABB
• Alstom
• Hawker Siddley
• Internal Audit
• Focus on planned maintenance

3
NETWORK MASTERPLAN

• PSW Consulting Engineers were appointed to assist
  in the preparation of Short, Medium and Long term
  Transmission and Distribution plans for the
  Midrand Area of supply.
• NET Group Consulting Engineers were appointed to
  assist in the preparation of Short, Medium and
  Long term Transmission Plans for the entire
  Network excluding the Midrand Area of supply.
  They were also appointed to assist in preparing
  Distribution plans for three focus areas where
  loading and network problems were being
  experienced in the Siemert Road, Randburg and
  Roodepoort Areas.
• Eskom (PTM) were also appointed to do
  pre-engineering studies at Fordsburg, Prospect,
  Delta, Kelvin and Orlando substations

4
Findings

• PSW Midrand Report
• The infrastructure in Midrand supply area is
  relatively new with an average age of between 15
  20 years. There are certain areas however which
  are appreciably older and will require upgrading
  and refurbishment in the Short term
• The infrastructure needs to be extended to meet
  projected future load growth

5
Substation Transformers Overview

• Detailed audit undertaken by Rotek and CPs Test
  Branch
• Significant number (52) of high risk transformers
  identified in terms of standard assessment
  parameters (moisture, DP, gases, acidity etc.)
• Age profile of transformers indicates urgent need
  for refurbishment / replacement programme
• Programme designed to eliminate backlog by 2010
  (or sooner) thereby greatly improving reliability
• Refurbishment programme to continue to reduce
  life cycles and conditions to acceptable levels

6
Sample Transformers Age Profile
7
Transformer Refurbishment 5 Year Plan
Note Total Trfr 250 Refurbished and
maintained 45 52 to be addressed
8
MV Switchgear Overview

• Detailed audit undertaken by OEMs e.g. Rotek,
  Siemens
• Significant number of high risk switchboards
  identified in terms of standard assessment
  parameters, particularly oil insulated units
• Age profile of transformers indicates urgent need
  for refurbishment / replacement programme for
  switches gt25 years
• Programme designed to eliminate backlog by 2010
  (or sooner) thereby greatly improving reliability
• Refurbishment programme to continue to reduce
  life cycles and conditions to acceptable levels

9
Age Profile All MV Switches
10
MV Switchgear Programme
11
Protection Audits by OEMs and Eskom

• Audits on secondary plant equipment focusing
  mainly on protection were conducted by
• ABB
• Siemens
• Eskom PTM
• Alstom
• And Internal Staff

12
Findings

• Main protection is prone to malfunction
• Backup protection in most cases is out of
  specification
• 70 of protection relays gt 20 years old, no
  spares available
• The suite of electro mechanical relays per line
  should be replaced with new electronic relays
  catering for the complete set of protection
  requirements, including disturbance recording.
• Protection Schemes - 40 of the Overcurrent and
  Earth Fault protection relays tripping
  characteristics had an error margin of
  approximately 60.
• Repairing and refurbishing of electro-mechanical
  relays is not a cost effective solution

13
Additional CAPEX Refurbishment Requirements
Minimum required to clear backlog in 5 Years
14
CAPEX requirements 2005/10
15
Upgrade Programme and Assumptions

• City Power has begun an intensive upgrade
  programme in order to achieve the following
• Reduced average age of equipment thru
  maintenance
• Replacement of obsolete equipment maintenance
  not feasible
• Upgrade of overloaded networks in order to
  compensate for natural and anticipated load
  growth
• Removal of equipment which is unsafe to operate
• Achieve standardisation across all areas in order
  to reduce downtime and have more available
  emergency stock
• Eradication of makeshift solutions
• Ensure higher plant availability

16
CAPEX and OPEX Investments per Region
17
2005/6 Capex Budget Allocation
18
Some Key projects for 2005/06

• Replacement and upgrade of substation
  transformers (17transformers ordered to be
  installed at Westfield, Cydna, Hursthill,
  Rosebank, Roosevelt, Grand Central, Bryanston,
  Allandale, Brynorth, Randburg, Olivedale and
  Fairlands)
• Protection upgrade at Kelvin and Prospect major
  intake points
• Replacement of obsolete feeder boards
• New substation at Bryanston to cater for pending
  re-zoning application
• Continuous upgrade and refurbishment of MV and LV
  infrastructure

19
Key priorities for 2005/06

• Reconfigure 275 KV using Dead Tank Circuit
  Breakers and Pantograph Isolators to address
  outages at Fordsburg, Prospect and for Delta to
  be able to handle the surplus load
• Installing prepayment meters in the identified
  areas in the South of Johannesburg
• Increase continued partnership with OEMs to help
  address critical network problems
• Increase our focus on planned maintenance
• The defective meters that have been identified
  and they will be replaced
• Increase in the reduction of illegal connections
  in identified areas
• A major focus will be dedicated to street lighting

20

• PROJECTS COMPLETED DURING 2004/5 FINANCIAL YEAR

21
2004/5 Randburg Area of Supply
22
2004/5 Randburg Area of Supply
23
2004/5 Hursthil Area of Supply
24
2004/5 Siemert Area of Supply
25
2004/5 Siemert Area of Supply
26
2004/5 Midrand Area of Supply
27
2004/5 Lenasia Area of Supply
28
2004/5 OLD JOHANNESBURG AREAS
ALL AREAS
29
2004/5 Alexandra Area of Supply, incl
electrification projects
30
2004/5 Roodepoort Area of Supply
31
2004/5 Roodepoort Area of Supply
32
2004/5 Roodepoort Area of Supply
33
2004/5 Roodepoort Area of Supply
34
Public Lighting Projects