On 29 November 2022 the AER published a determination clause 5.16B of the National Electricity Rules. The determination found that TransGrid is required to amend its Project Assessment Conclusions Reports for both the North West Slopes Area and Bathurst, Orange and Parkes Areas RIT-Ts by 1 February 2023. 

In conducting our review, we are not satisfied that Transgrid correctly applied the RIT-T as it: 

• did not use the scenarios from the most recent Inputs, Scenarios and Assumptions Report (IASR), and in departing from those scenarios, it did not provide demonstrable reasons for that approach
• did not demonstrate that the alternative scenarios selected were reasonable and deliver on a reasonable range of plausible states of the world
• did not use a common discount across all scenarios based on the discount rate in the Australian Energy Market Operator’s most recent IASR, and in departing from that report, it did not provide demonstrable reasons for that approach.