New South Wales
Australian Capital Territory
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Regulatory investment test and guidelines

The AER published its regulatory investment test for transmission (RIT-T) by 1 July 2010. The RIT-T has replaced the existing regulatory test for transmission investments and will commence on 1 August 2010. The regulatory test (version 3) continues to apply to projects which address a need on the distribution network.

The purpose of the RIT-T is to identify the transmission investment option which maximises net economic benefits and, where applicable, meets the relevant jurisdictional or Electricity Rule based reliability standards. The RIT-T provides a single framework for all transmission investments and removes the distinction in the regulatory test between reliability driven projects and projects motivated by the delivery of market benefits.

The AER has also published RIT-T application guidelines for the operation and application of the RIT-T (the application guidelines). The application guidelines are designed to provide guidance to businesses applying the RIT-T and enhance transparency and consistency in investment decision making.

An amendment to the National Electricity Rules (Electricity Rules) has changed the numbering of the provisions in the Electricity Rules associated with the RIT-T. The AER has published a cover letter (dated May 2013) to the RIT-T, outlining the implications of the amendment on the RIT-T and RIT-T application guidelines.

On 18 September 2017, we published amended RIT-T application guidelines as part of the transitional arrangements under the Australian Energy Market Commission’s (AEMC) replacement expenditure planning arrangements rule change (“repex rule change”).

The RIT-T application guidelines and RIT-T instrument on this page have been superseded (see guidelines to make the integrated system plan actionable for the current versions).