Transgrid has recently published a Project Specification Consultation Report (PSCR) for maintaining reliable supply to Western Sydney.
Forecasts from Endeavour Energy show rapid demand growth in the Western Sydney and Aerotropolis areas due to the connection of new data centres and ongoing development of commercial and residential lands and associated infrastructure in the area. There is an emerging risk of unserved energy at the Sydney West Bulk Supply Point (BSP) due to increasing summer demand exceeding the firm capacity at the site. This will result in load shedding under single or multiple outages of 330/132 kV transformers at Sydney West BSP to ensure loads are within the ratings of the remaining in-service transformers.
In the absence of network investment, our central maximum demand forecast for the Western Sydney area (Latest POE50 demand forecast) is expected to exceed the firm transformer capacity at Sydney West BSP from 2025/26. The difference between forecast maximum demand and firm transformer capacity at this BSP will increase from 48 MVA in 2025/26 to 791 MVA in 2032/33.
If there is a single or multiple outage of 330/132 kV transformers at the Sydney West BSP, and this contingency event occurs at or near times of high demand, load shedding will be required to maintain load below the firm capacity of the remaining in-service transformers. Based on probabilistic planning studies of transformer failure rates and repair times, we estimate expected unserved energy of 5 MWh in 2025/26, increasing to approximately 2,036 MWh in 2031/32, and 11,307 MWh in 2047.
We have commenced this RIT-T to assess options which will enable us to meet our reliability requirements in the Sydney West area in view of the significant increase in forecast demand. We consider this a ‘reliability corrective action’ under the RIT-T as the proposed investment is for the purpose of meeting externally imposed regulatory obligations and service standards, i.e., Schedule 5.1.4 of the National Electricity Rules (NER).
In the PSCR Transgrid presented two credible network options that would meet the identified need from a technical, commercial, and project delivery perspective. The optimal commercially and technically feasible option presented in this PSCR – Option 1 (Install a new 330/132 kV 375 MVA transformer at Sydney West BSP) – is the preferred option to meet the identified need.
The estimated capital cost of this option is approximately $24.78 million ($2022-23) +/- 25 per cent. Transgrid is the proponent of the proposed network project.
Transgrid welcomes written submissions on materials contained in this PSCR. Submissions are particularly sought on the credible options presented and from potential proponents of non-network options that could meet the technical requirements set out in this PSCR. Submissions are due on 20 July 2024.
In accordance with the requirements of the National Electricity Rules, a summary of the PSCR is made available on the AEMO website. A copy of the PSCR can be obtained from Transgrid’s website or by emailing regulatory.consultation@transgrid.com.au.