Still running your grid like it’s built for spinning turbines? In a world of inverter-based renewables, that’s like trying to steer a sailboat with the engine off. Australia just flipped the script with a 205MW/410MWh grid-forming battery that shows how storage can set the tempo for a renewable grid.

The problem: renewables without the old-school safety net

As coal plants retire and solar and wind surge, traditional grid inertia and fault current are fading. That creates headaches: frequency wobbles, weak system strength, and slower recovery from disturbances. The National Electricity Market (NEM) has adapted fast, but the physics have changed. Batteries are now the stabilizers of choice, with grid-forming batteries increasingly doing the heavy lifting. According to AEMO’s Q3 2025 Quarterly Energy Dynamics, batteries made up 46 percent of the connection pipeline capacity, roughly 70 percent of which is grid-forming, with 2,936MW/6,482MWh added since Q3 2024. Evening battery discharge jumped 177 percent year-on-year, helping to flatten price spikes by displacing gas and hydro.

The solution: grid-forming batteries set the beat

Enter grid-forming batteries. Unlike grid-following inverters (which simply sync to the grid’s existing voltage waveform), grid-forming systems act as a voltage source. They establish and regulate voltage and frequency, deliver synthetic inertia via fast active power response, and contribute fault current to anchor system strength. In plain English: they behave like the “big, stable machine” the grid was built around, but with silicon instead of steam.

Proof point: Queensland’s 205MW/410MWh Brendale BESS

Akaysha Energy’s Brendale battery in Queensland commissioned at 205MW/410MWh shows the concept in action. Using grid-forming inverters, it provides voltage support, system strength, and fast frequency control ancillary services (FCAS), while soaking up excess midday solar and firming evening peaks. It went live five months ahead of schedule and can supply up to two hours of power for around 200,000 homes, as reported in Energy Storage News. The project also inked an offtake arrangement that underscores how batteries monetize value across services, noted in this announcement.

Grid-forming vs. grid-following: what changes

• Voltage source vs. current source: Grid-forming behaves like a controlled voltage source with droop characteristics, while grid-following tracks an external voltage and frequency.
• Synthetic inertia: Grid-forming provides fast power injections to arrest frequency deviations, improving grid stability in low-inertia conditions.
• Fault current and system strength: Properly tuned grid-forming inverters contribute short-term fault current and stronger voltage support, aiding protection schemes and ride-through.
• Grid restoration: Grid-forming makes black start and islanded operation feasible, allowing staged re-energization of parts of the network.

How projects monetize grid-forming capability

• FCAS markets: Batteries earn from regulation and contingency services by responding in milliseconds, a trend reinforced in AEMO’s QED.
• System strength services: With new frameworks, grid-forming BESS can be procured or contracted to bolster weak parts of the grid, improving hosting capacity for inverter-based renewables as discussed in AEMO’s analysis.
• Energy shifting and price arbitrage: Charge from low-priced solar, discharge into evening peaks, dampening volatility and lifting revenue, also highlighted by AEMO.
• Constraint relief and curtailment reduction: By acting as a local stabilizer, grid-forming batteries unlock additional renewable output and interconnection capacity.
• Black start potential: Grid-forming capability supports staged re-energization, positioning BESS for restoration services alongside traditional assets, as noted in this report.

Why developers and utilities care

• Faster, cleaner interconnections: Developers can secure approvals in weak-grid areas by offering system strength and voltage control at the point of connection.
• Lower network reinforcement costs: Utilities can defer or right-size capex by contracting grid-forming services rather than overbuilding traditional plant.
• More renewable energy integration: Less curtailment, higher hosting capacity, and stronger ride-through keep wind and solar online when the grid hiccups.
• Revenue stacking: Energy arbitrage plus FCAS plus system strength contracts adds up, with the Brendale project demonstrating commercial appetite through its offtake, as noted in this announcement.

Practical design notes

• Pick the right control mode: Virtual synchronous machine or grid-forming droop control must be tuned to local grid conditions and protection settings.
• Engineer fault ride-through: Ensure sufficient short-term overcurrent capability without tripping inverters during faults.
• Plan standby power and losses: Grid-forming modes can draw more aux power; model these costs against revenue from stability services.
• Test for restoration: Coordinate black start procedures with the TSO and adjacent assets to validate safe islanding and resynchronization.

Bottom line

Battery energy storage systems are no longer just arbitrage machines. With grid-forming capability, they are the backbone of modern, renewable-heavy grids. Australia’s 205MW/410MWh Brendale battery proves it: set voltage and frequency, deliver synthetic inertia, anchor reliability, and get paid for it. The NEM’s rapid uptake shows where the world is headed, as noted in this study. It is a blueprint for how to integrate renewable energy at scale while keeping the lights on.