Transend - Appendix 5 Renewal capital expenditure - Australian ...

0BInvestment Evaluation Summary
TNM-GS-809-0720
reasons must be replaced. Inadequate safety at both sites in terms of safe working clearances, substandard
substation earthing, substation fencing are all strong reasons to undertake the project.
Dependence on [third parties] for interfaces for secondary equipment infrastructure is complex and
unacceptable in the long-term.
This project must achieve a simplification and standardisation of these substations which are both remote
and critical to the security of supply of Transend’s network.’
In addition, Ascension Consulting agreed with the approach undertaken with regard to the development of the
Tungatinah Substation 110 kV redevelopment project and fully supported the project implementation strategy.
Transend considers that continuing to operate assets that have been independently identified as presenting significant
safety risks and being in poor condition is unacceptable.
2 PROJECT OVERVIEW
The planned redevelopment and rationalisation of Tungatinah Substation and Tarraleah Switching Station includes the
replacement, rationalisation and reconfiguration of all 110 kV primary equipment (including circuit breakers,
disconnectors, current and voltage transformers) and replacement of all protection and control equipment. The
redevelopment will address significant safety issues at both sites and improve the reliability of electricity supply by
replacing assets that are in poor condition and susceptible to failure. The project also includes the reconfiguration of the
existing 110 kV ring bus bar arrangements to address operational issues and improve operational flexibility.
Figure 2 presents an image of Tungatinah Substation and Tarraleah Switching Station, which are located on opposite
sides of the Nive River, approximately 400 metres apart.
Figure 2 – Image of existing Tarraleah Switching Station (left) and Tungatinah Substation (right)
Figure 3 presents a summary of the age of the key 110 kV assets (by category) at Tungatinah Substation and Tarraleah
Switching Station by asset replacement cost (note that the scope of this project does not include replacement of the
power transformers). Figure 3 clearly illustrates that the majority of the assets included in the Tungatinah Substation
110 kV redevelopment project are well beyond their nominal service lives of 45 years for primary assets and 15 years for
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