WEM Electricity Statement of Opportunities

The Wholesale Electricity Market (WEM) Electricity Statement of Opportunities (ESOO) is an annual publication that provides forecasts for the WEM over the 10-year outlook period.

The WEM ESOO helps inform the planning and decision-making of market participants, new investors and policy-makers by advising on the additional generation, storage and network investment required to maintain reliability and security in the WEM and the South-West Interconnected System (SWIS).

The ESOO also plays an important role in the WEM’s Reserve Capacity Mechanism (RCM) process by forecasting the Peak and Flexible Reserve Capacity Target (RCT) for each Capacity Year in the outlook period, and setting parameters that determine Peak and Flexible Reserve Capacity Requirement (RCR) and type of capacity required to maintain reliability in the relevant Reserve Capacity Cycle.

2025 WEM ESOO

AEMO published the 2025 WEM ESOO report on 24 June 2025.

The 2025 WEM ESOO informs the planning and decision-making by WEM participants, investors and policymakers, by providing information on and projections of:

• Electricity consumption and demand across a range of weather and growth scenarios.
• Electricity supply from generation, storage, and Demand Side Programmes (DSP).
• The Peak Reserve Capacity Target (RCT), used to identify the capacity needed to meet the reliability standard.
• The Flexible RCT, to set the requirement to meet the largest expected Four-Hour Demand Increase (FHDI).
• Power system reliability and supply-demand balance.
• Electric Storage Resource (ESR) and DSP requirements, including the ESR Duration Requirement (ESRDR).
• The minimum Capability Class 1 and Class 3 requirement.
• SWIS System Strength to address reduced levels of synchronous generation and increased levels of inverter based resources (IBR).  

2025 Reserve Capacity Information Pack

The 2025 Reserve Capacity Information Pack for the 2025 Reserve Capacity Cycle is available in the links at the bottom of this page, along with historical information packs.

The 2025 Reserve Capacity Information Pack contains the following information:

• Reserve Capacity Requirement for the 2027-28 Capacity Years.
• Instruction on how to obtain the 2025 Request for Expressions of Interest (EOI) and the 2025 EOI summary from the WEM Website.

Feedback

AEMO welcomes feedback on the 2025 WEM ESOO.

Please direct any questions relating to the 2025 WEM ESOO to the WA Future System & Design team.

Email: wa.futuresystemdesign@aemo.com.au

Please direct any questions relating to the Certified Reserve Capacity process for the 2025 Reserve Capacity Cycle to the WA Capacity Investment & Assessment team. 

Email: wa.capacity@aemo.com.au

2025 WEM ESOO documents and supporting materials

Previous WEM ESOO Documents