This page groups the year-by-year searches for the small-scale technology percentage. The numbers below come from the Clean Energy Regulator’s published percentages and the reports that accompanied them. The regulator holds the authoritative table under “previous small-scale technology percentages”, so verify any figure before you rely on it for a contract.
STP by year
| Year | STP (per cent) | Note |
|---|---|---|
| 2019 | 21.73 | Reported, approximately 37.4 million STCs |
| 2020 | 24.40 | Reported, approximately 42.6 million STCs |
| 2021 | 28.80 | Estimated 42.1 million STCs |
| 2022 | 27.26 | |
| 2023 | 16.29 | About 28.5 million STCs |
| 2024 | 21.26 | |
| 2025 | 13.89 | |
| 2026 | 11.67 | Based on 24.1 million estimated STCs |
Reading the series
The STP rose through 2021 as rooftop solar boomed and the regulator forecast more certificates. It then fell sharply in 2023, rose again in 2024 and fell in 2025 and 2026. The swings are not just about volumes. The calculation includes a cumulative adjustment for how many certificates were over- or under-surrendered in previous years, which can pull the percentage up or down by several points on top of the underlying forecast. You can see this in the 2026 formula, where 2,617,218 certificates are subtracted from the 24.1 million estimate.
The trend is clear: each year needs fewer certificates relative to electricity bought, as deeming periods shorten and fewer systems qualify for large claims. We explain the mechanics in how the STP is calculated.
Why you should not read it as a price signal
A higher STP does not mean a higher STC price. The percentage is designed to match demand to forecast supply, so a bigger percentage usually reflects a bigger forecast of creation. The market price reacts to the gap between forecast and actual, not the headline percentage. See what the STP means for STC prices.
Forward numbers
Non-binding estimates for 2027 and 2028 are 10.75 and 7.77 per cent. They are projections, and the binding figure for each year is set only by 31 March of that year. See binding and non-binding STPs for the difference.
What this means for installers
The STP is a retailer-side number. It tells you about the health of demand for your certificates over time, and the long fall suggests the scheme is winding down on schedule towards 2030, as the deeming period guide describes. For payment, check the pricing page, and for the market in general read how STC trading works.