When a business asked for a 150 kW rooftop system before 1 October 2026, the quote could not include an STC discount. The incentive worked differently and arrived slowly, through LGCs. For installs from that date, up to 1 MW, the quote can include an upfront STC discount. LGCs now matter mainly for older systems above 100 kW and for projects above 1 MW. The new band is covered in mid-scale solar STCs.
What changes
| Up to 100 kW | 100 kW to 1 MW, from 1 Oct 2026 | Above 1 MW, or above 100 kW before 1 Oct 2026 | |
|---|---|---|---|
| Certificate | STCs | STCs | LGCs |
| Timing | Upfront at install | Upfront at install | As the system generates |
| Deeming | Shortens each year (5 years for 2026) | Fixed five years | None, actual output |
| Accreditation | Installer and product based | Installer and product based | Power station accreditation |
| Value per unit | About $38 to $40 per STC | About $38 to $40 per STC | Roughly $6 to $9 per LGC in September 2026 |
Mid-scale applications open mid to late November 2026, according to the Clean Energy Regulator, so hold the claim until then.
Practical steps for the installer
- Check the install date and the system size before choosing the certificate pathway.
- For LGC projects, quote on the net system price, with LGCs as a separate stream for the customer.
- Tell the customer about accreditation, metering and registration costs.
- Decide who will manage the LGC process: the customer, you or a specialist agent.
- Make sure metering supports reporting from the first day of generation.
- Document the install to the standard the CER expects.
Steps are covered in how to create LGCs.
Talking to the customer
For a system installed before 1 October 2026 above 100 kW, a short script helps: ‘Because the system is above 100 kW and was installed before the new rules, it does not receive the upfront discount. Instead, you can register the system as a power station and earn certificates for every megawatt hour it generates. Those are worth less per unit but arrive for as long as the system runs.’ Pair that with a simple year-one estimate of generation and certificate income, so the customer sees the number and not just the concept. For newer installs up to 1 MW, show the STC count and the date applications open.
What this means for installers
Commercial customers often ask for the same “rebate” they heard about for homes. Set expectations by size and date: an upfront STC discount up to 1 MW from 1 October 2026, and a smaller ongoing LGC revenue above that. Other incentives for businesses are outlined in business solar rebates in Australia, and the STC trading page covers the upfront side. The resources hub has related guides, and the LGC value explainer covers the numbers.