Heat pumps are not calculated like solar panels. You do not multiply kilowatts by a zone rating. Instead each registered model carries a tested energy performance, and the Clean Energy Regulator converts that into STCs for your zone and install year.
What sets the count
- The model. Registered performance data decides how much energy the unit is deemed to displace. Higher capacity and better efficiency generally mean more certificates.
- The zone. The regulator sets five postcode zones for air source heat pumps, based on regional climate. The same model earns a different count in different zones.
- The install year. The regulator’s method applies a factor that falls with the deeming period: 0.5 for 2026, 0.4 for 2027, 0.3 for 2028, 0.2 for 2029 and 0.1 for 2030. The register’s own figures reflect the install date you enter.
- The installation type. New and replacement installs are evidenced differently. See the installation type guide.
Heat pump STC rebate in 2026: amount
Tens of certificates, not hundreds. As an illustration only, a unit that registers 25 STCs for your zone and the 2026 install date has a value of roughly $950 to $1,000 at the $38 to $40 range seen at the time of writing. A smaller or less efficient unit earns less, and a high-performing one in the right zone more. Do not take the 25 as a rule: the register is the source.
Heat pump STC rebate in 2027
The factor drops from 0.5 to 0.4, so the same unit in the same zone creates around 20 percent fewer STCs from 1 January 2027, with a further step each year to 2030. If the example unit above earns 25 in 2026, the equivalent count in 2027 would be about 20, or roughly $760 to $800 at today’s prices. The scheme ends on 31 December 2030. A related page covers whether heat pump STCs fall every year.
Turning STCs into dollars
The discount equals the count times the price per STC, less whatever margin your installer takes. Ask your installer to show the STC count and the dollar value on the quote, and which year they have used.
How to check yours
- Find the exact model and tank size on your quote.
- Look it up on the Clean Energy Regulator’s register of solar water heaters. See how to check hot water STC eligibility.
- Read the figure for your zone and install date, or use the regulator’s calculator.
- Compare it with the count printed on the quote.
What this means for you
If you are a homeowner, the discount is real money and gets smaller each January, so book the install with the date in mind. If you are an installer, price every job off the registered figure and keep your evidence complete. The hot water STCs pillar explains the claim, the hot water checklist lists the photos, and pricing shows today’s rate.