CER SRES Solar Water Heater and Heat Pump Eligibility Rules: Australian Regulations

Key Takeaways

• Solar water heaters must have a capacity of up to 700 L to be eligible for STCs under the Australian SRES (August 2026).
• Air source heat pumps are capped at 425 L capacity for STC eligibility under the Australian SRES (August 2026).
• Small-scale Technology Certificates (STCs) must be created within 12 months of installation (August 2026).
• The deeming life baseline for STC calculations is currently set at 10 years (August 2026).

What are the Australian CER SRES eligibility rules for solar water heaters and heat pumps?

The Australian Clean Energy Regulator (CER) Small-scale Renewable Energy Scheme (SRES) sets specific eligibility rules for solar water heaters and air source heat pumps to qualify for Small-scale Technology Certificates (STCs). These rules include limitations on system capacity and requirements for listing on an official register.

The table below outlines the primary provisions for solar water heaters and heat pumps under the Australian SRES.

Figures as of August 2026.

How do we verify these Australian SRES rules?

We verify these eligibility rules by directly consulting the official publications of the Australian Clean Energy Regulator (CER). Our information is drawn from the CER's website, specifically their sections detailing eligibility for small-scale systems and the deeming period decline. We checked these sources on 23 August 2026 to ensure the information is current.

What are the capacity limits for solar water heaters and heat pumps?

For solar water heaters, the system capacity must be up to 700 L to be eligible for STCs (August 2026). If a model has a capacity over 700 L, it requires additional documentation to qualify for STCs (August 2026).

For air source heat pumps, the system capacity must be no more than 425 L to qualify under the small-scale scheme (August 2026). Systems exceeding this capacity are not eligible for STCs under these specific provisions.

What are the STC creation and deeming period requirements?

Small-scale Technology Certificates (STCs) must be created within 12 months of the installation date (August 2026). This is a critical timeframe for installers and system owners.

The deeming life baseline for STC calculations is currently set at 10 years (August 2026). The method for calculating STC entitlements for solar water heaters is outlined in the Renewable Energy (Method for Solar Water Heaters) Determination 2016 (August 2026). When the deeming period is multiplied by the relevant multiplication factor, the result is rounded down to the nearest whole number (August 2026). The multiplication factor decreases by 0.1 as the deeming period decreases (August 2026).

What should you consider when selecting an eligible system?

When choosing a solar water heater or heat pump for STC eligibility in Australia, you must ensure the system meets the specified capacity limits. For solar water heaters, this means a capacity of up to 700 L, or preparing for additional documentation if it exceeds this (August 2026). For air source heat pumps, the limit is 425 L (August 2026).

It is also mandatory for solar water heaters to be listed on the official register of solar water heaters (August 2026). You should confirm this listing before purchase.

Understanding these rules helps ensure your system qualifies for STCs, which can reduce the upfront cost of your solar hot water or heat pump installation. For broader context on STC eligibility, you can refer to our guides on CER SRES Solar PV 100kW Eligibility and STC Rules and Australia Solar STC Deeming Period and Battery Multiplier Guide. If you are concerned about product compliance, our guide on CER SRES Recalled Solar Product and STC Eligibility provides further information. You can also estimate your potential solar system size with our solar sizing tool.