Grid-forming batteries: Australia’s 100-project push

BP

06 Dec 2025 — 4 min read

Still curtailing solar at noon? That’s the grid equivalent of parking a Ferrari in first gear.

As wind and solar surge, many grids are shedding the natural inertia that came for free with big spinning turbines. The result: touchier voltage, quicker frequency swings, and more curtailment than anyone wants to admit. Enter grid-forming battery energy storage systems (BESS) — the fastest-growing way to add synthetic inertia, black start capability, and robust voltage and frequency control without rebuilding the grid from scratch.

What is a grid-forming battery, really?

In plain English: a grid-forming inverter turns a battery into a strong, stable “voltage source” that sets the tempo, not just follows it. Unlike conventional grid-following inverters, grid-forming (GFM) controls can create and hold voltage and frequency, ride through disturbances, and instantly inject or absorb power to keep the system in tune. Think of it as a digitally savvy replacement for the stabilizing role spinning machines used to play.

If you want the deeper cut, leading system engineers frame GFM BESS as near-ideal voltage sources that stabilize weak grids, improve system strength, and support fault recovery — capabilities laid out in this ESIG 2025 brief and the functional expectations summarized by NERC’s grid-forming inverter specification. Recent technical studies also show GFM batteries outperform traditional controls during faults and dynamic swings, providing faster voltage and frequency support and synthetic inertia, as noted in this Scientific Reports paper.

Why Australia is sprinting ahead

Australia’s National Electricity Market (NEM) is seeing coal retirements and high renewable penetration move faster than conventional grid upgrades. Operators need stability services yesterday, not in five years. That’s why grid-forming batteries are multiplying across the map, from trials to commercial deployments.

Australia’s market operator AEMO now tracks nearly 100 grid-forming BESS projects across the NEM, reflecting a strategic pivot toward inverter-based stability, synthetic inertia, and islanding capability — as summarized in this Modo Energy explainer and AEMO/ARENA’s technical guidance and project portfolio shared in this ARENA webinar deck.

If you’ve followed headline projects like Hornsdale, Dalrymple, Wallgrove, and Torrens Island, you’ve already seen the trajectory: big batteries graduating from fast frequency response to grid-forming duties that strengthen weak parts of the network and reduce curtailment risk. The takeaway is simple — the stability value is real, and it’s arriving faster with software than with new steel in the ground.

PJM and the market lesson for the rest of the world

Across the Atlantic, PJM has been a proving ground for battery participation in ancillary services. Frequency regulation has long been the main revenue stack for batteries, historically via the fast RegD signal. The market is evolving again — PJM redesigned its regulation product to merge signals and improve energy neutrality and performance measurement, with batteries still front and center. See the technical context in this NREL 2024 report and the redesign analysis in Modo Energy’s 2025 brief. For the nuts and bolts, PJM’s market manuals are the reference of record, including Manual 11 and generator requirements in Manual 14D. Revenue concentration in regulation is documented by the market monitor in PJM’s State of the Market.

Why it matters: as more grids follow PJM’s lead in valuing fast, accurate frequency control, GFM batteries will not only earn from regulation — they will reduce the need for costly grid reinforcements by delivering system strength, inertia-like response, and black start capabilities where they are most needed.

EV fast charging and buffer batteries: a preview of distributed stability

High-power EV hubs are increasingly pairing on-site batteries to shave peaks, protect local feeders, and, in some markets, bid into fast frequency services. In the UK, batteries dominate National Grid ESO’s Dynamic Containment program — the service is designed for sub-second frequency containment, detailed in ESO’s Dynamic Services documentation and auction data pages like this dataset. Flagship charging sites are experimenting with large buffers — for instance, Tesla’s 168-stall “Oasis” Supercharger in California pairs solar with multiple Megapacks to manage ultra-high loads on-site, as covered by Drive Tesla and Teslarati. The direction of travel is clear: flexible storage at high-load nodes will increasingly support both customers and the grid.

How grid-forming batteries keep the lights on

Synthetic inertia: Fast active power injection arrests frequency drops after a disturbance, improving Rate of Change of Frequency (RoCoF) performance. See conceptual frameworks in ESIG and NERC.
Voltage source behavior: GFM inverters act like strong grid voltage sources, improving fault ride through and system strength in weak-grid areas, as highlighted in this ESIG brief.
Black start and islanding: The right controls and coordination let GFM batteries energize dead networks and form resilient islands. Requirements and performance expectations are outlined in NERC guidance.
Curtailment reduction: By stabilizing local voltage and frequency, GFM BESS help keep PV and wind online during grid stress, a trend discussed in Australian guidance and trials such as ARENA’s materials and Modo Energy’s explainer.

What it means for utilities, developers, and high-load customers

Utilities and TSOs: Target GFM BESS where system strength is lowest. Specify grid-forming capabilities in procurements and interconnection agreements. Build validation plans around performance metrics such as inertia contribution, fault ride through, and black start readiness. See testing guidance in ESIG.
Developers: Stack services. Regulation and fast frequency response still pay, but system-strength and curtailment-avoidance value will increasingly be recognized by operators. Track rule changes (for example, PJM’s regulation redesign in this analysis) and align inverter controls with GFM specifications like NERC’s.
High-load customers: Consider on-site buffers with GFM capabilities for large EV hubs, data centers, and industrial sites. They can slash demand spikes, ride through disturbances, and in some jurisdictions, earn from ancillary services. UK ESO’s Dynamic Containment structure is explained here: official service page.

Bottom line

Grid-forming batteries are moving from pilots to portfolio strategy. Australia’s nearly 100 projects are a bellwether: stability services are shifting to software-defined power. Markets like PJM show that once you pay for fast, accurate control, batteries show up. The next step is clear — specify grid-forming in your projects, test rigorously, and place these assets where they neutralize the toughest grid problems first.