Inverters fail more often than panels. After eight to twelve years, a replacement is routine. The question owners ask is whether the replacement earns a rebate, and the straight answer is no, unless something else changes.
Why a like-for-like swap earns nothing
STCs are created for the capacity of a small generation unit, measured by panel kW. If the same panels continue to generate and only the inverter changes, there is no new capacity to certify. The panels already earned their certificates when the system was first installed, and the CER does not allow a second claim for them.
When the upgrade does earn STCs
An inverter replacement can sit alongside a claim in two situations.
- Panels are added. If the owner adds capacity, the new panels can create STCs as an extension. The inverter must be on the approved list at the date of the addition, and it must have the capacity for the larger array. See adding panels to an existing system.
- The whole system is replaced. If all components are decommissioned and replaced with new approved ones, it may be a replacement system. See replacing solar panels and old systems.
Worked example
An owner replaces a failed inverter and adds 3 kW of panels in zone 3 in 2026. The 3 kW earns 3 x 1.382 x 5 = 20 STCs, about $760 to $800 at the roughly $38 to $40 spot range at the time of writing. The inverter swap earns nothing, and the old 6.6 kW of panels earns nothing new.
Hybrid inverters and batteries
A common reason to upgrade now is a battery. A hybrid inverter can make the system battery-ready, and the battery may earn its own STCs under the Cheaper Home Batteries Program, which works with existing solar. The inverter swap itself is not claimable. See retrofitting a battery.
What this means for installers
Make sure the invoice and quote separate the inverter, the added panels and any battery. Do not apply an STC discount to an inverter-only job. If you are adding capacity, check that the inverter’s rating and approval status support the claim, and keep the old and new serial numbers. Use the installation type guide to label the job correctly.
For process and payment, see STC trading and current rates.