Retailers carry two renewable energy obligations at once. Each has its own percentage, its own certificate, and its own price.
What each percentage does
The renewable power percentage, or RPP, is the share of electricity acquired by a liable entity that must be backed by Large-scale Generation Certificates. The small-scale technology percentage, or STP, is the share that must be backed by STCs. A retailer calculates both from the same electricity acquisitions, multiplies by each percentage, and surrenders that number of certificates.
For 2026 the STP is 11.67 per cent. In 2020, as an example of how the numbers compare, the RPP was 19.31 per cent and the STP was 24.40 per cent. Check the Clean Energy Regulator for the current RPP.
Why there are two
The Renewable Energy Target was split in 2011. The Large-scale Renewable Energy Target covers power stations, which create LGCs from metered output. The Small-scale Renewable Energy Scheme covers rooftop solar, solar hot water and heat pumps, which create STCs up front on deemed output. A history is in the STC scheme history page.
How they differ
| STP | RPP | |
|---|---|---|
| Certificate | STC | LGC |
| Source | Small-scale systems | Large generators |
| Price control | $40 ex GST Clearing House | None |
| Recent price | roughly $38 to $40 | roughly $6 to $9 (September 2026) |
| Surrender | Quarterly | Annual |
The price control is the key difference. Retailers can always buy STCs at $40, whereas LGCs trade freely and are oversupplied and cheap in 2026. See LGC versus STC for the finer points.
How the calculation differs
The RPP is based on the large-scale target and how many LGCs are expected to be available, which depends on the pipeline of large wind and solar. The STP is based on a forecast of rooftop and small-scale certificate creation. The STP formula is explained in how the STP is calculated.
Mid-scale solar
From 1 October 2026, solar above 100 kW and up to 1 MW creates STCs, not LGCs, with a five-year deeming period. That moves some generation from the large-scale side to the small-scale side. Above 1 MW remains in LGCs. Our mid-scale solar page covers the rules.
What this means for installers
Small systems create STCs only. If you build above 1 MW, you are in LGC territory, and the pricing and surrender rules differ. For STCs, start with the pricing page and how STC trading works.