Big batteries are displacing plans for gas peaking plants because they are cheaper, faster to build, and emission-free.
Recent major battery projects, including AGL’s Tomago BESS and Alinta’s Reeves Plains BESS, have replaced fully permitted gas projects that never advanced.
Similar shifts are happening in Queensland’s Western Downs, where approved gas units have stalled while new batteries and solar projects move forward.
Batteries are also being built alongside existing gas plants, such as Torrens Island and Mortlake, where they are cannibalising gas generation.
Industry experts say gas projects face long turbine supply delays, high fuel costs, and greater regulatory scrutiny, making them less viable.
Batteries, in contrast, are modular, quicker to permit, and offer faster response to demand, with uptake in 2025 already at record highs.
Big batteries are reshaping the NEM, setting discharge prices nearly three times higher than gas, and becoming major revenue sources for energy companies.
In its annual results, AGL declared batteries its new cash cow as coal and gas exit the grid, with cumulative capacity forecast to quadruple to 14.3 GW by 2030.
Analysts suggest new gas plants are unlikely to be built by private companies and will instead rely on government underwriting as backup capacity.
Long-term, alternatives such as diesel or green fuels may replace fossil gas for rare backup events, leaving batteries as the dominant new-build technology.