For businesses, the “rebate” is the same mechanism that households use, with a higher threshold at the top since 1 October 2026. The year-specific view is in commercial solar rebate 2026. This page sets out the structure.
Systems up to 100 kW: STCs
A commercial system up to 100 kW with annual generation under 250 MWh can create STCs, using the same formula as a house. For a 2026 install, the deeming period is five years. As an example, a 99 kW system in zone 3 earns 99 x 1.382 x 5 = 684 STCs, rounded down. At roughly $38 to $40 at the time of writing, that is around $26,000 to $27,000 as an upfront discount.
Systems above 100 kW and up to 1 MW: STCs from 1 October 2026
Solar installed from 1 October 2026 in this band creates STCs with a fixed five-year deeming period. A 300 kW system in zone 3 earns 300 x 1.382 x 5 = 2,073 STCs. The Clean Energy Regulator says applications open mid to late November 2026. See mid-scale solar STCs.
Above 1 MW, and older large systems: LGCs
Larger systems, and systems above 100 kW installed before 1 October 2026, are accredited as power stations and create LGCs for the electricity they actually generate. The value arrives gradually, at a much lower price per certificate (roughly $6 to $9 in September 2026). See LGC vs STC.
State and territory programs
Some states run schemes that reward efficiency or provide incentives to businesses, such as certificate schemes or low-interest finance. These change often, and eligibility varies. Check the official page for your state’s energy agency.
Practical points for business owners
- Check the thresholds first. Size (100 kW and 1 MW) and install date (1 October 2026) decide which certificate you get.
- Get the assignment right. The business owner signs it, and the ABN and GST details need to match.
- The small-scale deeming period steps down every January. Delays cost certificates. Mid-scale systems have a fixed five years.
- Tax. Ask your accountant about depreciation and any available deductions for the year of installation.
From the desk: do not assume the headline STC discount is the whole business case. Compare it with bill savings and any state support, and model the payback with and without it.
Questions to ask before you sign
Ask the installer which scheme the system falls under, what the STC count and dollar value are, and what the deeming period assumption is. Ask what happens to the discount if the grid connection is delayed. For systems above 1 MW, ask who will handle LGC accreditation and what the expected annual certificate value is.
What this means for you
If you are a business owner, ask your installer to show the STC count and the dollar value on the quote. If you are an installer, see STC trading for how to sell those certificates, pricing for current rates and the resources hub for guides.