The State Government of Western Australia estimates up to 51.1 GW new renewable energy and storage capacity to be required by 2042 through its South West Interconnected System (SWIS), including 41.8 GW large scale solar and wind, to meet industrial electricity demand which could grow by 7.2 GW according to initial modeling.

It would be almost 10 times the amount of generation capacity currently on the SWIS. In 2022, the utility scale generation capacity in SWIS was 5.9 GW comprising some 1.2 GW of large-scale wind and solar and 3.1 GW gas-fired generation capacity.

Early assessment shows 96% of electricity produced in the SWIS to come from renewable energy by 2042.

“The modelling shows large-scale solar paired with long duration energy storage (LDES) as the most cost-efficient form of firmed renewable generation. This combination is expected to be built across the SWIS,” reads the SWIS Demand Assessment Report released by the state.

The government has also committed AUD 126 million additional funding in the 2023-24 State Budget for Western Power to start early planning and works on the state-owned electricity grid.

It will also work with industrial users to determine their investment in the SWIS network, the government added, to ensure cost of new network infrastructure for industrial demand is not passed onto household energy consumers.

“An expanded grid is the most cost-efficient way of supporting decarbonization as it can reach further for wind and solar. The SWIS cannot rely on other electricity systems to support it, so having a strong transmission backbone is critical for reliable supply,” said State Energy Minister Bill Johnston.

Western Australia plans to exit coal and not commission any new natural-gas fired plant after 2030 as it announced last year saying it will instead invest AUD 3.8 billion in new green power infrastructure including storage on the SWIS (see Western Australia To Exit Coal By 2030).