The AER Cost-Benefit Analysis Guidelines 2024 set out how Australian transmission network businesses must evaluate major investments under the Regulatory Investment Test for Transmission (RIT-T) and the Integrated System Plan (ISP). The 2024 update strengthens the economic assessment framework by requiring clearer valuation of emissions reductions, improved treatment of concessional finance so that consumer benefits are captured, and better alignment between project planning and regulatory processes. The guidelines also recognise the role of early works in accelerating delivery of critical projects and emphasise stronger community engagement to support social licence for new transmission infrastructure. They require transparent, well-documented assumptions, robust scenario analysis, and sensitivity tests to address uncertainty in demand, technology, and costs. Overall, the updated guidance promotes consistent, evidence-based assessment of electricity-transmission investments.
