World’s biggest isolated grid says it has more than 12 GW of renewables ready to connect

One of the world’s most isolated electricity grids, and likely the biggest, Western Australia’s South West Interconnected System (SWIS), has a “connection-ready” pipeline of more than 12 gigawatts of renewable energy projects, the state’s government-owned network company has revealed.

In an update issued last week, Western Power’s executive manager of energy transition and sustainability, Matt Cheney, said the SWIS had a total of 12.81 gigawatts (GW) of new solar, wind and battery projects lined up to plug in to the grid, as of the end of June, 2025.

“Over the past year, we have been building a clearer picture of where renewable investment is likely to occur, future load forecasts, and project readiness,” Cheney said.

“Looking ahead Western Power’s pipeline of connection-ready projects as of June 2025 is 12.81GW.”

Cheney says Western Power issued seven new generators with network access offers in the 2024-25 financial year, including battery energy storage systems (BESS) and wind and solar farms that will bring an additional 759 megawatts (MW) of clean energy onto the SWIS.

The final two of those projects included the Merredin BESS, which is one of four big battery projects that won the first storage tender in WA under the federal government’s Capacity Investment Scheme.

The 100 MW/400 MWh Nomad Energy and Atmos Renewables project reached financial close in early July, clearing the way for its construction in the south west of Western Australia.

Also issued an Access Offer by Western Power is Frontier Energy’s Waroona Renewable Energy Project, one of Australia’s first true solar and battery hybrid developments, with 120 MW of PV and an 80 MW, 360 MWh DC-coupled battery storage system.

Cheney says the Access Offers are the culmination of months of collaboration between project proponents and Western Power, and mark the start of grid connection works, a key phase in the development journey for major new renewable energy projects.

“This highlights our collaboration with industry, and we’re proud to partner with our customers to bringnew capacity onto the SWIS safely and efficiently,” he said.