Transgrid has published the Project Assessment Conclusions Report (PACR) for Maintaining Reliable Supply to the Bathurst, Orange and Parkes areas in Central West NSW. The PACR has been prepared as the final step in the Regulatory Investment Test for Transmission (RIT-T) process and follows the Project Assessment Draft Report (PADR) published in February 2022.
Transgrid’s latest forecasts indicate that electricity demand is expected to increase substantially in the Orange and Parkes areas going forward due to expected demand growth associated with the expansion of some existing large mine loads in the area, the planned connection of new mine/industrial loads and general load growth around Parkes, including from the NSW government’s Parkes Special Activation Precinct (SAP).
Schedule 5.1.4 of the National Electricity Rules (NER) requires Transgrid to plan and design equipment for voltage control to maintain voltage levels within 10 per cent of normal voltage. The NER also requires the power system to be operated in a satisfactory operating state, which requires voltages to be maintained within these levels, both in normal operation and following any credible contingency event.
Transgrid have undertaken planning studies that show that the current central west network will not be capable of supplying the combined increases in load in the area without breaching the NER requirements. Specifically, we forecast significant under-voltage conditions in this region of our network if action is not taken.
If the longer-term voltage constraints associated with the load growth in Orange and Parkes areas are unresolved, it could result in the interruption of a significant amount of electricity supply to customers under both normal and contingency conditions.
In February 2022, Transgrid published the Project Assessment Draft Report (PADR) and invited written submissions on the material contained in the PADR. In response to the PADR, Transgrid received submissions from 11 parties. Transgrid engaged further with parties to confirm the status and technical feasibility of the options, which involved the provision of further information from these parties. Transgrid thanks those who made a submission throughout the RIT-T process.
The assessment in this PACR finds that a non-network solution provided through new Battery Energy Storage Systems (BESS) at Parkes and Panorama along with the installation of dynamic reactive power support devices in the near term is the preferred option for stage 1 of the project. Stage 2 of the project involves a new 132 kV transmission line between Wellington and Parkes in the future, with the date of this line depending on outturn demand forecasts.
In accordance with the requirements of the Rules, a summary of the Project Assessment Conclusions Report 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