Transgrid has published the Project Assessment Conclusions Report (PACR) for Improving Stability in South Western 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 September 2021.
South Western New South Wales (NSW) has seen significant growth in renewable generation connections to the transmission network as part of the wider energy market transition. More than 790 MW of renewable generation has connected in South Western NSW since December 2015 and approximately 580 MW of renewable generation is currently in the process of being commissioned.
This new generation is having an impact on how this part of the power system operates, with the resultant changes in power flows leading to an increasing risk of system instability going forward. This resulted in the Australian Energy Market Operator (AEMO) introducing an operational constraint in the NEM Dispatch Engine (NEMDE) in May 2020 to limit power flows, in order to manage the risks to system stability.
We have identified the opportunity to strengthen the transmission network in south-western NSW to relieve this constraint and provide market benefits to the National Electricity Market (NEM).
In September 2021, Transgrid published the Project Assessment Draft Report (PADR) and invited written submissions on the material contained in the PADR. In response to the PADR, we received submissions from six parties. We engaged further with parties to confirm the status and technical feasibility of the options, which involved the provision of further information from these parties. Thank you to those who made a submission throughout the RIT-T process.
The assessment in this PACR finds that a new Darlington Point to Dinawan 330 kV transmission line coupled with an interim 3-year network support contract with a battery energy storage system (BESS) solution (‘Option 4’) is the preferred option for meeting the identified need across all scenarios and sensitivities assessed. Option 4 is expected to deliver approximately $91 million in net benefits over the assessment period (on a weighted-basis).
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.