Latest Project Marinus modelling shows substantial market benefits under updated AEMO assumptions

Final market modelling ahead of construction has found Project Marinus will save the National Electricity Market (NEM) approximately $3 billion in the cost of meeting future electricity demand.

Marinus Link Pty Ltd (MLPL) re-engaged Ernst & Young (EY) to update its market benefit analysis of future scenarios with and without Project Marinus, following the release of the Australian Energy Market Operator’s (AEMO) Final 2025 Inputs, Assumptions, and Scenarios Report (IASR).

EY’s updated analysis is part of the continued independent scrutiny of Marinus Link in accordance with the Australian Energy Regulator’s Regulatory Investment Test for Transmission.

MLPL has calculated the net market benefit using EY’s modelled gross benefits and applying a Delphi weighted average across various future scenarios.

“After accounting for the costs to invest in Marinus Link, this updated modelling shows the NEM will save billions in avoided costs under a range of future scenarios,” MLPL CEO Stephanie McGregor said.

“Coal stations are closing, and we’re electrifying our economy at the same time. A future with Marinus Link is critical for reliability and keeping system costs as low as possible across all states in the NEM,” she said.

Net market benefits are the overall resource cost savings resulting from Project Marinus proceeding. It compares the expenses for new generation and transmission assets, fuel, and other resources that would be needed to meet future electricity demand.

“Essentially, new assets will be needed to meet future electricity demand, and Project Marinus is the lower-cost solution.”

Marinus Link Stage 1 is expected to commence construction in 2026, pending final environmental and regulatory approvals.

Marinus Link and the North West Transmission Developments (NWTD) are collectively known as Project Marinus.

MLPL is responsible for progressing the Marinus Link project and is jointly owned by the Commonwealth of Australia, the State of Tasmania, and the State of Victoria.

TasNetworks is responsible for progressing the NWTD project and is owned by the State of Tasmania.             

View EY’s full Gross Market Benefit Assessment of Project Marinus