Transgrid has published the Project Assessment Conclusions Report (PACR) for Maintaining voltage levels in Northern NSW. 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 July 2023.
The Australian Energy Market Operator (AEMO) forecasts that minimum demand in NSW will rapidly decline over the next 10 years due to ongoing growth in distributed solar (PV) generation. In Northern NSW, growth in small to large scale embedded generation connecting to the Essential Energy network is forecast to continue, driving declining minimum demand in this region.
The Northern NSW region is supplied by a series of 132 kV transmission lines which form a link between Glen Innes, Armidale and Tamworth. Transgrid’s power system studies show that the declining minimum demand in these areas mean that the electricity transmission system in these areas is at risk of exceeding allowable voltage levels during times of low demand and in particular when nearby generators are unable to provide reactive power support.
Transgrid is required to manage the risk of system voltages exceeding their allowable limits as set out in the National Electricity Rules (NER) and the NSW Electricity Reliability and Performance Standards 2017.This RIT-T therefore examines various network and non-network options to address the excess voltage levels to ensure compliance with the requirements of the NER and provide the greatest net benefit to the market.
Transgrid has commenced this RIT-T to assess options to ensure the above NER requirements continue to be met in the longer term in Northern NSW considering the declining minimum demand. Transgrid considers 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.
The assessment in this PACR finds that the installation of a 132 kV 25 MVAr reactor at Inverell 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