Commercial Solar Changes From 1 October 2026: What Australian Businesses Need to Know
A significant change to Australia’s solar incentive framework comes into effect on 1 October 2026, expanding access to upfront support for larger commercial solar systems.
The Small-scale Renewable Energy Scheme (SRES), which previously applied to eligible solar PV systems up to 100kW, is being expanded to include eligible systems above 100kW and up to 1MW. DCCEEW
For many commercial, industrial and agricultural businesses, this changes the financial equation when considering a larger solar installation.
What is changing on 1 October?
Until now, the 100kW threshold has created a significant divide between small-scale and larger commercial solar projects.
Eligible systems up to 100kW could access Small-scale Technology Certificates (STCs), which provide an upfront financial benefit under the SRES.
Larger systems operated under different arrangements.
From 1 October 2026, eligible solar PV systems above 100kW and no more than 1MW will also be able to participate in the SRES and create STCs. Clean Energy Regulator
In practical terms, this means considerably larger commercial solar projects may now qualify for an upfront financial incentive through STCs.
Why does this matter for commercial solar?
The change is particularly relevant to businesses with larger electricity requirements and sufficient space for systems exceeding 100kW.
This may include:
- warehouses and logistics facilities
- manufacturing and industrial sites
- agricultural businesses and processing facilities
- schools and educational facilities
- hospitals and healthcare facilities
- community organisations
- larger commercial properties. DCCEEW
Previously, businesses considering a system larger than 100kW needed to assess the project under the large-scale renewable energy framework.
The expanded SRES provides a different pathway for eligible mid-scale projects, potentially improving the upfront commercial proposition for systems between 100kW and 1MW.
A fixed five-year deeming period
One of the important details of the new arrangements is how STCs will be calculated.
Eligible mid-scale systems between 100kW and 1MW will receive a fixed five-year deeming period. This differs from systems up to 100kW, where the STC deeming period continues to decline as the SRES approaches its scheduled end in 2030. Clean Energy Regulator
This fixed five-year period applies to eligible mid-scale systems each year through to 2030. DCCEEW
The actual value available to an individual project will depend on factors including system capacity, location, certificate creation and the applicable STC market value.
For this reason, businesses should assess the incentive as part of the complete commercial and technical feasibility of their project rather than relying on a headline rebate figure.
What systems will be eligible?
The expansion does not mean every commercial solar system below 1MW automatically qualifies.
For new installations, the maximum system size is 1MW. Where an existing solar power station or related solar PV systems are already located onsite, the total capacity must also remain within the applicable 1MW limit.
Projects must meet SRES requirements as well as relevant accreditation, electrical safety, planning, approval and network connection requirements. DCCEEW
This makes early project planning particularly important.
System size should be determined by the site’s energy requirements, available infrastructure, network conditions and commercial objectives, rather than simply designing a project around the maximum incentive available.
What if a project is already being planned?
Timing is particularly important for businesses currently considering or developing a commercial solar project.
The new rules apply to eligible systems installed from 1 October 2026. Clean Energy Regulator
However, there is an important administrative distinction.
The Clean Energy Regulator has advised that STC applications for mid-scale systems are expected to open in mid to late November 2026. Eligible systems installed on or after 1 October can apply once the application process opens. Clean Energy Regulator
Businesses do not necessarily need to wait until applications open before progressing an eligible installation, but the project must satisfy the applicable requirements.
STCs aren’t the only option
For systems between 100kW and 1MW, project owners will be able to choose between accessing the upfront benefit available through STCs or participating in the Renewable Electricity Guarantee of Origin (REGO) scheme and creating REGO certificates.
The Clean Energy Regulator advises participants to consider which pathway best suits their circumstances because choosing one may affect eligibility under the other. For example, a system receiving STCs cannot create REGO certificates during the applicable deeming period. Clean Energy Regulator
This is another reason larger commercial projects should be assessed individually rather than assuming the same approach is appropriate for every business.
What should businesses do now?
For businesses considering commercial solar between 100kW and 1MW, the October changes create an opportunity to reassess projects that may previously have been delayed or designed around the old 100kW threshold.
The starting point should still be a proper assessment of:
- electricity consumption and load profile
- available roof or ground space
- existing electrical infrastructure
- network connection requirements
- appropriate system capacity
- project costs and available incentives
- expected energy generation
- commercial objectives and project delivery model.
A larger incentive does not automatically mean a larger system is the right solution. Good commercial solar design starts with understanding the site and building the system around the business.
Planning a commercial solar project?
The expansion of the SRES represents a significant change for Australia’s mid-scale commercial solar market.
For businesses considering systems between 100kW and 1MW, projects installed from 1 October 2026 may now have access to an upfront STC benefit that was previously unavailable at this scale.
Westsun Energy works with commercial and industrial clients across the complete project lifecycle, including feasibility, system design, approvals, network requirements, procurement, construction and project delivery.
If your business is considering a commercial solar project, or you want to understand how the 1 October 2026 changes could affect a project already in planning, contact Westsun Energy to discuss your site and requirements.
Information in this article is general in nature and is current as at September 2026. Eligibility for Small-scale Technology Certificates is subject to the requirements of the Small-scale Renewable Energy Scheme and Clean Energy Regulator. Project-specific financial, technical and regulatory advice should be obtained before proceeding.
Official information: https://cer.gov.au/schemes/renewable-energy-target/small-scale-renewable-energy-scheme/small-scale-renewable-energy-systems/mid-scale-solar
Speak With Westsun Energy
The proposed changes could make larger commercial solar systems more accessible than ever before.
If you’d like to understand how the expanded incentives may apply to your business, contact Westsun Energy to discuss a tailored commercial solar solution designed for long-term performance, reliability and value.
Contact Westsun Energy for a Commercial Solar Assessment in Perth or across Western Australia.
