Transgrid has published the Project Assessment Conclusions Report (PACR) for maintaining reliable supply to Western Sydney. The PACR is the final step in the Regulatory Investment Test for Transmission (RIT-T) process and follows the Project Specification Consultation Report (PSCR) published in April 2024.
The latest Endeavour Energy demand forecast for Sydney West BSP shows significant demand growth which is mainly driven by spot load including data centres, metro train lines and large commercial and residential development around the new airport in Western Sydney.
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 130 MVA in 2025/26 to 694 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 26 MWh in 2025/26, increasing to approximately 1411 MWh in 2031/32, and 13517 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).
The assessment in this PACR finds that the installation of a 330/132 kV 375 MVA transformer at Sydney West BSP is the preferred option to meet the identified need.
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 PACR can be obtained from Transgrid’s website or by emailing regulatory.consultation@transgrid.com.au.