Increasing capacity for generation in the Wagga North Area

The Wagga North area has seen significant growth in renewable generation connections to the transmission network, as part of the wider energy market transition. Currently, approximately 409 MW of renewable generation is already in service in this area. 

Lines 9R5, 9R6 and 991 play a central role in transmitting the electricity from these renewable generators via our Wagga North 132/66 kV and Wagga 330/132 kV substations. Our analysis shows that the load requirements on Lines 9R5 and 9R6 exceed their thermal rating under system normal network conditions if the current in-service renewable generators in the Wagga North area are dispatched to their maximum capacities.

An opportunity has been identified to upgrade the 132 kV Lines 9R6 and 9R5 supplying Wagga North 132/66 kV substation to alleviate potential thermal constraints due to recent renewable generation developments in the Wagga North area. In all credible scenarios there is expected to be significant economic benefit to the National Electricity Market (NEM) to strengthen the transmission network to relieve this constraint and realise net market benefits by avoiding curtailment of low-cost renewable generation in the Wagga North area.

Transgrid is applying the Regulatory Investment Test for Transmission (RIT-T) to increase overall net benefits in the NEM through improving capacity and relieving existing constraints on renewable generation in the Wagga North area. This will enable greater output from renewable generation in this region of the NEM.

Transgrid must show that the preferred option for proving net benefits to the market by improving capacity for renewable energy generation in the Wagga North area will deliver the greatest net benefit to energy consumers. The net benefits delivered by the project are assessed using the Regulatory Investment Test for Transmission (RIT-T) administered by the Australian Energy Regulator (AER).

The RIT-T assess network and non-network solution options from a technical and economic perspective by:

• Informing stakeholders of the investment need and proposed options to address this need.
• Testing the market for alternative and more efficient solutions.
• Explaining to stakeholders the basis on which the preferred option has been selected. 

In December 2024 we published a Project Specification Consultation Report, the first step in the RIT-T process.

The PSCR detailed the need to increase overall net market benefits to the market by improving capacity for renewable generation in the Wagga North area and describes the credible options to meet the need, including technical characteristics that would be required of a non-network option.

We received submissions from seven parties in response to the PSCR. Of the seven parties that submitted to the PSCR, one party has requested confidentiality, therefore we will not publish their material on our website.

The following submissions are approved for publication. For privacy purposes, personal information has been redacted from these published submissions.

We are in the process of preparing a Project Assessment Draft Report (PADR) which will include a full quantitative analysis of the proposed options and expected net market benefit across a range of scenarios and sensitivities. Alongside the PADR, we will publish a market modelling report and NPV model outcomes. We anticipate the PADR will be published between October and December 2025. Publication of the PADR will be followed by a six-week consultation period, during which we invite written submissions on the material contained in the PADR.