STC financial incentives help reduce the upfront cost of solar power, solar hot water, and heat pump systems.

Small-scale Technology Certificates (STC) are currently used to reduce the purchase price of your new Solahart system, and can often save you thousands of dollars. The number of certificates created will vary based on:

  • the size and model of the solar water heater or PV system you choose
  • the location of the installation (or zones)
  • the amount of electricity in megawatt-hours (MWh) the system will generate or displace over what is known as a deeming period. The deeming period is from the year of installation to the 31st December 2030:

    • For a solar hot water system, each STC represents 1 megawatt-hour (MWh) of electricity displaced over the deeming period.
    • For a solar power system, each STC represents 1 megawatt-hour (MWh) of renewable electricity produced over the deeming period.


The STCs produced by the installation of a Solahart system can be traded and sold on the open market, or your local dealer can exchange them at a discounted price of your system to the current value of STCs. This saves you the hassle of dealing with the certificates post-purchase and reduces the initial capital outlay required.

How much are these incentives worth on a typical Solahart System?

Both Solar Power and Solar Hot Water systems have a reduced deeming period as the countdown to 2030 gets closer.

If you are still unsure if now is the time to go solar, the following table should help you understand what will happen over the next few years and how it will affect the overall cost of making the switch to solar.

Going solar is a decision that perhaps shouldn’t be left until the last moment, also considering that the value of STCs may also change in the future.

  SOLAR POWER SYSTEM SOLAR HOT WATER SYSTEM
Date from Deeming Period Example
6.6kW System (Zone 3)
Total STC Certificates		 @$36/STC
(Zone 3)		 Example
302L SHW System (Zone 3)
Total STC certificates		 @$36/STC
(Zone 3)
From 01/01/2022 9 Years 82 $2,952 25 $900
From 01/01/2023 8 Years 66 $2,376 22 $792
From 01/01/2024 7 Years 58 $2,088 19 $684
From 01/01/2025 6 Years 49 $1,764 16 $576
From 01/01/2026 5 Years 41 $1,476 14 $504
From 01/01/2027 4 Years 33 $1,188 11 $396
From 01/01/2028 3 Years 24 $ 864 8 $288
From 01/01/2029 2 Years 16 $ 576 5 $180
From 01/01/2030 1 Year 8 $ 288 2 $72
After 31/12/2030 Nil 0 $ 0 0 $ 0

Figures based on the number of certificates @ $36 per certificate. STCs are variable and subject to change and correct as at 01/03/2022.