Overview
The Capacity Investment Scheme 2025 Western Australia Wholesale Electricity Market (WEM) Design Paper was updated to correct an error in the RCC dates.
Please note facilities nominating to participate in the 2026 RCC will be merit assessed against their pathway to achieving COD by 1 October 2028.
Updates were published 14 March 2025. Please make sure you are using the corrected version.
The Capacity Investment Scheme (CIS) is an Australian Government revenue underwriting scheme to accelerate investment in:
renewable energy generation (generation), such as wind and solar
clean dispatchable capacity (dispatchable), such as battery storage.
The Scheme provides a long-term revenue safety net that decreases financial risk for investors. This ensures more renewable energy projects get built.
CIS tenders seek competitive bids across the National Electricity Market (NEM) and the Western Australia Wholesale Electricity Market (WEM). Underwriting contracts support renewable generation and dispatchable projects to:
help deliver the Australian Government’s 82% renewable electricity by 2030 target
deliver an additional 32 GW of capacity by 2030
support electricity generation growth and reliability as demand grows and ageing coal-fired power stations retire
place downward pressure on electricity prices.
The Capacity Investment Scheme 2025 Western Australia Wholesale Electricity Market (WEM) Design Paper describes the CIS and WEM, and sets out potential design parameters for a proposed combined WEM Generation and Dispatchable tender in 2025.
The Western Australia Wholesale Electricity Market (WEM) operates in the South West Interconnected System (SWIS), which covers the south-west of WA.
The WEM has key design features which makes it different to the NEM on the east coast, with the most significant being:
the Reserve Capacity Mechanism (RCM) which seeks to procure capacity on behalf of the market through Capacity Credits, providing project owners a revenue stream
the substantial role of bilateral contracting and net settlements where the majority of energy and Capacity Credits in the WEM are traded bilaterally, either between market participants or between the generation and retail arms of a gentailer.
As this would be the first CIS tender to underwrite renewable generation capacity in the WEM, you can now provide feedback on the proposed design, with a particular focus on:
WEM generation CIS design parameters
eligibility and merit criteria for generation tenders
approach to the inclusion of hybrid projects.
To have your say:
The Capacity Investment Scheme 2025 Western Australia Wholesale Electricity Market (WEM) Design Paper has been updated to correct an error in the RCC dates. The latest version of the paper was published 14 March 2025.
Please note the correction on page 20 - facilities nominating to participate in the 2026 RCC will be merit assessed against their pathway to achieving COD by 1 October 2028.
read the latest version of the Capacity Investment Scheme 2025 Western Australia Wholesale Electricity Market (WEM) Design Paper.
detail your feedback in your organisation, group or individual submission
lodge your submission through the Have our Say platform by 10:00am AWST / 1:00pm AEDT 31 March 2025.
Feedback received through this consultation will be used to inform the design and implementation of future CIS tenders in the WEM, including Tender Guidelines and draft Capacity Investment Scheme Agreements.
