Insights
- Current data indicates a potential record of around 3.2 GW of small-scale renewable energy generation capacity was added in 2024.
- STCs can be created over a 12-month period with the bulk created after 3 months, so by around April there will be a clearer picture of 2024 capacity.
- In 2025, an estimated 2.9 GW to 3.2 GW of rooftop solar is expected to be added to the grid.
- Recent trends suggest that capacity may currently be heading for the top end of this range. The lower bound is based on modelling from consultants prepared in mid-2024 to inform the STP for 2025.
- Battery installations reached a record 10% in 2024 based on data voluntarily provided to the CER.
- The share new of installations with batteries is likely higher, with market analysts estimating a 2023 figure of around 17%.
- More than 100,000 air source heat pumps were installed under the SRES in 2024. This was nearly a quarter lower than 2023 installations. This is likely driven by changes in the NSW Hot Water System Rebate (NHWR) eligibility criteria to prevent ‘double dipping’ with the SRES.
On this page
- Market dynamics
- Possibly a new record for rooftop solar installations
- Continued growth in battery-connected systems
- Supplementary figures
Market dynamics
In Q4 2024, 8.6 million STCs were created, bringing the 2024 total to 34.1 million. On average, around 656,000 STCs were created per week throughout 2024. This was above the average of around 646,000 required to meet the compliance demand set for the 2024 STP.
Description
This figure shows the weekly supply of STCs in 2024. It also shows the required weekly supply of STCs (646,154) to meet the 2024 STP.
This figure is interactive. Hover over/tap each bar to see the number of STCs. Hover over/tap along the line to see the required weekly supply. Click/tap on the items in the legend to hide/show data in the figure.
Small print
Required STC supply refers to the estimated number of STCs to be created (33.6 million) to meet the annual STP liability and under/over supply from previous years. Some weeks are spread across multiple months, the month label refers to the month as at the end of the week.
The surrender deadline for the Q4 2024 compliance period was 14 February 2025. A total of 7.0 million STCs were surrendered at a compliance rate of 102%. Over the course of 2024, 39.1 million STCs were surrendered compared to the 37.9 million annual compliance requirements. Surrenders above the requirement can occur when there is a discrepancy between the relevant acquisitions or exemptions used to calculate the STP and the final figures from the year. In 2024, relevant acquisitions were 4.5 TWh higher and exemptions were 0.1 TWh lower than expected. This resulted in liable entities surrendering 1.2 million more STCs than the compliance requirement set out in the 2024 STP.
The 2025 STP has been set at 13.89%. The STP is set by the Minister for Climate Change and Energy each year and aims to set demand to match projected STC creation. That is, all certificates expected to be created in a year are required to be surrendered by liable entities, considering any over or underachievement from the previous year. The 2025 STP will require liable entities – typically electricity retailers – to surrender a cumulative total of 24.9 million STCs to meet the compliance requirements.
Estimated STC creation for 2025 is driven by the projected number of household solar PV systems and the STCs per system. By design, as the SRES phases down to its 2030 close, the annual percentage reduction in STCs per system increases by a sizeable and growing amount in percentage terms. For example, the decline from 7 years of upfront STCs in 2024 to 6 years in 2025 equates to a 14.3% reduction in rebate. On the other hand, system prices and payback periods have continued to fall as noted in chapter 2. While a lower rebate lowers demand for household PV other things equal, the CER expects that 2025 added solar capacity will be similar to 2024.
Small-scale technology certificate (STC) reported spot and clearing house prices
Note: This figure is not interactive.
Description
This figure shows the daily closing STC spot price over time. It also shows the STC clearing house price.
Small print
Pricing data is complied from trades reported by CORE markets and may not be comprehensive. Prices are shown from 1 December 2019 to 14 February 2025.
Read more about buying and selling STCs, including through the clearing house.
The STC spot price remained at $39.90 for the majority of Q4 2024. This was due to the STC clearing house remaining in deficit for most of the quarter. The STC clearing house entered surplus from 17 December 2024 but fell back into deficit in the lead up to the Q4 surrender deadline on 14 February 2025.
Possibly a new record for rooftop solar installations
Strong Q4 2024 solar PV installation figures has kept the possibility of a record year of installed capacity alive. At the end of 2024, the validated annual capacity was marginally higher than the 2023 capacity at the same point in time. STCs can be created up to 12 months from installation, with the bulk created after 3 months, so a clearer picture of 2024 will be available by April 2025. At the time of publication, it is likely that 2024 capacity will be higher than the 3.14 GW installed in 2023. It could match or exceed the pandemic induced record of 3.2 GW in 2021.
The average system size installed in 2024 was 10.0 kW, 0.6 kW higher than 2023. This continues the trend of increasing average system sizes each calendar year, more than offsetting the annual decline in total installations.
Description
This figure shows the installed capacity and the number of small-scale rooftop solar installations over time.
This figure is interactive. Hover over/tap each bar to see the installed capacity. Hover over/tap along the line to see the number of installations. Click/tap on the items in the legend to hide/show data in the figure.
Small print
Small-scale rooftop solar systems must have a capacity of less than 100 kilowatts (kW). A 12 month creation period for registered persons to create small-scale technology certificates applies under the Renewable Energy (Electricity) Regulations (2001). Data for installations and installed capacity in 2023 and 2024 have been lag-adjusted to account for the 12 month creation rule and are estimates only. These figures will be updated throughout the year as more data is reported to us. Data is subject to change and totals may not sum due to rounding.
Continued growth in battery-connected systems
There was a significantly higher percentage of new small-scale systems being installed with batteries in 2024 relative to previous years. Data voluntarily reported to the CER shows that 10% of systems were battery-connected in 2024, up from 8% in 2023. The data also indicates a strong uptick of systems reported as having batteries in Q4, largely driven by the NSW battery incentive scheme. As discussed in previous reports, only systems installed from November 2024 onward are eligible for that scheme.
Increasing capacity of storage will be important to ensure the rapid increase in generation from rooftop solar does not result in increasing curtailment of large-scale wind and solar to maintain power system security. In addition, increases in storage help allow further large increases of rooftop solar capacity to be connected without creating security issues in both low and high voltage networks or the need to forcibly ‘trip’ or tun off rooftop solar.
Description
This figure shows the proportion of small-scale solar installed under the Small-scale Renewable Energy Scheme (SRES) reported as battery-connected in NSW and in Australia over time.
This figure is interactive. Hover over/tap along the line to see the proportion of battery-connected small-scale rooftop installations. Click/tap on the items in the legend to hide/show data in the figure.
Small print
A 12 month creation period for registered persons to create small-scale technology certificates applies under the Renewable Energy (Electricity) Regulations (2001). Data has not been lag-adjusted and are subject to change. Battery data is voluntarily reported to the CER. The actual proportion of battery-connected solar installations may be higher.
Strong year for air source heat pumps despite lower incentives
The CER has validated the installation of more than 100,000 air source heat pump (ASHP) systems, and 2.7 million associated STCs in 2024. This is the second consecutive year where ASHP installations under the SRES have surpassed 100,000. Air source heat pumps are estimated to have displaced approximately 1,580 GWh of grid sourced electricity in 2024.
NSW’s quarterly air source heat pump installations continued to decline in Q4 2024, driven by reduced incentives offered under the NSW Government’s NHWR under its Household Energy-savings Upgrades program. Prior to this change, the ability to access both schemes reduced the cost of an average ASHP installation in NSW by up to 33%. Consequently, NSW has observed a significant year-on-year decline in its total air source heat pump installations in 2024, which were 52% lower than in 2023. By comparison, the rest of Australia saw a year-on-year increase in air source heat pump installations of 7% over the same period.
Lower NSW installations in Q3 and Q4 2024 meant that Victoria led the nation in air source heat pump installations in 2024, with more than 44,000 validated installations. Market intelligence suggests that installers have been shifting their operations to Victoria following the changes to the NSW rebate scheme.
2024 installation numbers have not been lag adjusted for the 12-month creation period and will increase over the course of 2025 as the CER validates more systems.
Description
This figure shows the number of air source heat pump installations under the Small-scale Renewable Energy Scheme (SRES) by state and territory over time. It also shows the number of STCs validated from these installations over time. Totals may not sum due to rounding applied to NT.
This figure is interactive. Hover over/tap each segment to see the number of installations. Hover over/tap along the line to see the number of STC validations. Click/tap on the items in the legend to hide/show data in the figure.
Small print
Where cell values are less than 10 data have been modified due to privacy considerations. In the figure these values appear as 10.
A 12 month creation period for registered persons to create STCs applies under the Renewable Energy (Electricity) Regulations (2001). STC validation data has been rounded to the nearest thousand. Data as at 31 December 2024 and has not been lag-adjusted. Data is subject to change.
Supplementary figures
Description
This figure shows the rooftop solar capacity installed under the Small-scale Renewable Energy Scheme by state and territory over time.
This figure is interactive. Hover over/tap each segment to see the number of installations. Hover over/tap along the line to see the number of STC validations. Click/tap on the items in the legend to hide/show data in the figure.
Small print
A 12 month creation period for registered persons to create small-scale technology certificates applies under the Renewable Energy (Electricity) Regulations (2001). Data for installations in 2023 and 2024 have been lag-adjusted to account for the 12 month creation rule and are estimates only. These figures will be updated throughout the year as more data is reported to us. Data is subject to change and totals may not sum due to rounding.
Description
This figure shows the proportion of rooftop solar systems installed under the Small-scale Renewable Energy Scheme by capacity band over time.
This figure is interactive. Hover over/tap each segment to see the proportion. Click/tap on the items in the legend to hide/show data in the figure.
Small print
A 12 month creation period for registered persons to create small-scale technology certificates applies under the Renewable Energy (Electricity) Regulations (2001). Data as at 31 December 2024 and has not been lag-adjusted. Data is subject to change. Totals may not sum to 100% due to rounding.
Description
This figure shows the small-scale rooftop solar average system size over time.
This figure is interactive. Click/tap along the line to see the average system size.
Small print
Small-scale rooftop solar systems must have a capacity of less than 100 kW. A 12 month creation period for registered persons to create small-scale technology certificates applies under the Renewable Energy (Electricity) Regulations (2001). Data for average system size in 2023 and 2024 have been lag-adjusted to account for the 12 month creation rule and are estimates only. Data is subject to change.
Description
This figure shows the volume of STCs transacted and the number of transactions, excluding STC Clearing House transactions, over time.
This figure is interactive. Hover over/tap each bar to see the number of STCs. Hover over/tap along the line to see the number of transactions. Click/tap on the items in the legend to hide/show data in the figure.
Description
This figure shows STC supply over time.
This figure is interactive. Hover over/tap each bar to see the number of STCs.
Description
This figure shows small-scale rooftop solar replacements as a proportion of total installations by state and territory over time.
This figure is interactive. Hover over/tap along the line to see the proportion of replacement installations. Click/tap on the items in the legend to hide/show data in the figure.
Small print
Replacements represent small-scale rooftop solar systems categorised in the Renewable Energy Certificate (REC) Registry as replacements. The installation type data field was added to the REC Registry in late 2020. Data as at 31 December 2024 and has not been lag-adjusted. Data is subject to change due to the 12 month creation rule.