AEMO published several key forecasting and planning reports on 31 July 2025 for use in the 2026 Integrated System Plan (ISP) process, including the 2025 Inputs Assumptions and Scenarios Report (IASR), 2025 Electricity Network Options Report and 2025 Gas Infrastructure Options Report.
The publication of these reports aligned with the halfway point in the two-year cycle to develop the next ISP. More than 1,100 stakeholders contributed input and feedback, including more than 240 individual submissions.
AEMO has now commenced modelling with the best-available information to inform the Draft 2026 ISP.
In August, AEMO updated the final 2025 Electricity Network Options Report and Inputs Assumptions and Scenarios Report to align with the publication of the 2025 Victorian Transmission Plan. In addition, some other minor updates have been made including the transfer limits for the South West New South Wales renewable energy zone, treatment of gas-powered generation for the Sydney, Newcastle, Wollongong sub-region of the model, and clarifying assumptions about distribution network opportunities.
To find out more about these reports, you can listen to the 2025 Forecasting and Planning Reports webinar held on 12 August 2025. It was very well attended and involved almost 300 stakeholders.
Access a recording of the webinar and the presentation
In the coming months AEMO will develop the appropriate weightings to apply to the scenarios in the Draft 2026 ISP. This will include a deliberative process for a subset of informed stakeholders to share their views on the likelihood of various key scenario parameters.