Transgrid Project Specification Consultation Report: Maintaining voltage levels in Northern NSW

Transgrid has recently published a Project Specification Consultation Report (PSCR) for maintaining voltage levels in the Moree and Inverell area in Northern New South Wales.

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. Our 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.

We are 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.

We have 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. 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.

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 2 (Install a 132 kV 25 MVAr reactor at Inverell) – is the preferred option to meet the identified need.

The estimated capital cost of this option is approximately $5.41 million +/- 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 25 October 2023.

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