Reinforcing the NSW Southern Shared Network (Humelink) RIT-T dispute

On 16 August 2021, Wunelli Pty Ltd. (Wunelli) lodged a dispute in relation to the conclusions made in TransGrid’s Reinforcing the NSW Southern Shared Network (Humelink) regulatory investment test for transmission (RIT-T).

The dispute was raised under clause 5.16B of the National Electricity Rules (NER) on the grounds that the Humelink RIT-T PACR fails to identify and consider all credible options to address the network need. Among other interrelated issues outlined in its dispute notice, Wunelli contended:

  • There are other network distinct configurations of the preferred option, each having materially different route lengths, geographic or environmental risks, construction costs and network benefits, and also differing in their relationship to existing assets.
  • It is not clear whether the route corridors for costing the different options have been optimised for double circuit construction.
  • TransGrid has provided insufficient transparency about the double circuit configuration of the preferred option.

Determination

On 24 November 2021, following a review of the dispute, and further information provided by TransGrid, the AER finds that TransGrid did not apply the Humelink RIT-T PACR in accordance with the NER in relation to its consideration of credible options.

Specifically, TransGrid could reasonably have been expected to include in the Humelink RIT-T analysis, a full double circuit option for the path between Maragle and Bannaby as a credible option. In relation to additional grounds raised in the dispute notice, the AER is satisfied that TransGrid applied the Humelink RIT-T PACR in accordance with the NER and RIT-T requirements.

To ensure that the RIT-T meets the requirements of the NER and to ensure transparency of the RIT-T analysis, the AER requires that TransGrid amend the Humelink PACR to include a full double circuit option for the path between Maragle and Bannaby as a credible option. These amendments must also include supporting economic and sensitivity analysis to test the robustness of this option to differing assumptions.

TransGrid is required to amend its PACR by 23 December 2021.

AER- Determination on RIT-T dispute - TransGrid -Humelink-24 November 2021 ( PDF 524.94 KB )

Background documentation

TransGrid - Response to AER information request- 9 November 2021 ( PDF 235.74 KB )

TransGrid - Response to AER information request-28 October 2021 ( PDF 696.42 KB )

TransGrid- Response to AER information request- 18 October 2021 ( PDF 229.79 KB )

TransGrid - Response to AER information request-5 October 2021 ( PDF 623.95 KB )

TransGrid - Response to AER information request-1 September 2021 ( PDF 471.75 KB )

Wunelli - Dispute Notice under Rule 5.16B of the NER - Humelink RIT-T - 16 August 2021 ( PDF 588.46 KB )