Add storage capacity to your existing modular battery with a compatible expansion module, installed after compatibility and firmware checks so the whole battery stack works together.
From $3,490 (Per module, installed), including GST. Indicative starting price: the final fixed price is confirmed in writing after a site assessment.
Household energy use changes. An electric vehicle, a heat pump, a home office or a growing family can quickly outpace the battery you installed a few years ago. If your battery is modular, adding an expansion module is often the most cost-effective way to increase storage, because it reuses the existing inverter, cabling and battery management system instead of starting again.
Expansion modules start from $3,490 per module, installed. This is an indicative starting price; the final fixed price is confirmed in writing after we confirm compatibility with your battery.
Adding capacity sounds simple, but it only works when the battery management system accepts the new module and the inverter can make use of it. Rules differ between products: some series limit how many modules can be stacked, or how far apart in age the modules can be. We check these details for Sigenergy, GoodWe, Fox ESS and Sungrow modular batteries before quoting, and we will tell you if expansion is not the right choice for your system. Before recommending more storage, we also check whether your current battery is actually filling and emptying most days, because extra capacity only helps if there is surplus solar or a clear use for it.
Owners of modular batteries whose household use has grown, for example after adding an EV or electrifying the home.
Federal discount: the Cheaper Home Batteries Program may apply to eligible added capacity where the product, the installation and your total battery size meet the program rules. The program is tiered per kWh, and its value steps down every 1 January and 1 July to 2030. We confirm eligibility in your quote, and you should check current values on the official pages before signing.
Limits: adding modules increases stored energy, not the inverter's maximum power output. Mixing new and older modules can affect usable capacity and warranty terms, depending on the manufacturer's rules.
Price drivers: module capacity, the number of modules, any firmware or base unit changes, and access to the battery location.
1. Request an expansion quote and send your battery model and installation details.
2. We check compatibility, firmware, warranty terms and current battery performance.
3. You receive a fixed-price quote, including any federal discount that applies.
4. We order the module and schedule installation once it arrives.
5. Our team installs the module, updates firmware and tests the expanded battery.
The price shown is an indicative starting price per module; the final fixed price is confirmed in writing after compatibility checks and a quote.
Expansion is available only where the manufacturer supports adding modules of the same series to your battery.
The federal battery discount may apply to added capacity only where program rules and eligibility are met at the time of installation.
Warranty terms for mixed-age modules are set by the manufacturer and are confirmed before you accept.
Changes to battery capacity may require updated network or incentive paperwork, which we lodge for you.
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Prices include GST.
