In the transition to a net-zero energy system, the role of gas is shifting from a primary fuel source to a critical stabiliser that ensures reliability when renewable energy generation fluctuates. Just as a battery stores and discharges electricity when needed, gas infrastructure enables the storage and flexible release of energy, providing backup capacity during peak demand periods. This paper explores how gas serves as a ‘battery’ for the energy system, supporting grid stability, enhancing energy security, and integrating with emerging technologies.

1. Introduction

As Australia accelerates its transition towards renewable energy, managing intermittency in wind and solar power becomes a growing challenge. Gas plays an essential role in energy storage and release, acting as a dynamic reservoir that can be tapped into when renewables fall short. The concept of gas as a ‘battery’ underscores its value in stabilising energy systems, mitigating supply volatility, and ensuring consistent power delivery.

This paper examines gas’s role in energy storage, the significance of underground reserves and LNG terminals, and how emerging low-carbon alternatives like hydrogen can complement its function.

2. Gas as Energy Storage

Batteries store electricity for later use, but at present, large-scale battery storage solutions remain limited in capacity and costly for long-duration backup. Gas, on the other hand, is stored in vast underground reserves, LNG facilities, and pipeline networks, providing a large-scale, long-term energy storage solution. The 2024 Gas Statement of Opportunities (GSOO) highlights how gas reserves act as a buffer against energy shocks, ensuring supply security during demand spikes (50† 2024 Gas Statement of Opportunities [GSOO]).

Key forms of gas storage include:

• Underground gas storage (UGS): Enables the seasonal storage of gas for release during peak demand periods.
• Liquefied Natural Gas (LNG) terminals: Store gas in a compressed form for on-demand delivery.
• Pipeline network storage: Uses line pack capacity to regulate supply to the grid.

These mechanisms enhance energy reliability, particularly when renewable sources underproduce due to weather conditions (52† 2024 WA Gas Statement of Opportunities [WA GSOO]).

3. Gas as a Peaking Power Source

Gas-powered generation (GPG) provides fast-response electricity supply, acting as a stabilising force during:

• Periods of low renewable generation (e.g., overcast, windless days).
• High-demand scenarios (e.g., extreme weather events).
• Unexpected outages of coal or renewable plants.

According to the 2024 Electricity and Gas Networks Performance Report, GPG plays a vital role in meeting peak electricity demand while supporting grid resilience (55† 2024 Electricity and Gas Networks Performance Report).

4. The Future: Hydrogen and Renewable Gas Storage

As Australia moves towards a decarbonised energy future, gas infrastructure is evolving to store and distribute low-carbon alternatives. Key developments include:

• Green hydrogen production and storage: Electrolysis-driven hydrogen can be stored in existing gas networks and used in power generation.
• Biomethane integration: Renewable methane sources can supplement or replace natural gas in storage facilities.
• Hybrid energy systems: Combining battery storage with gas reserves to optimise grid stability (49† Future Gas Strategy Analytical Report).

By repurposing existing gas infrastructure, Australia can extend its storage capacity, providing a flexible and sustainable energy system.

5. Conclusion

Gas is no longer just a fuel for direct combustion—it is increasingly recognised as a critical energy storage medium, functioning as a battery for the energy grid. Its ability to provide scalable, on-demand backup ensures system resilience in an era of increasing renewable energy reliance. The integration of hydrogen, biomethane, and energy storage technologies will further enhance its role, ensuring Australia’s energy transition remains secure and reliable.

References
(Sources cited throughout the paper, including 2024 GSOO, Future Gas Strategy Analytical Report, Electricity and Gas Networks Performance Report, and relevant government policies.)