It is not actually a rebate
The scheme most people call “the solar rebate” is the Small-scale Renewable Energy Scheme (SRES), administered by the Clean Energy Regulator. It works by creating tradeable certificates called small-scale technology certificates, or STCs.
One STC represents one megawatt-hour of electricity that your system is expected to generate or displace. When you install a system you become entitled to a number of certificates, which have a market value. You assign them to your installer, and the installer deducts that value from your price.
The practical effect is a discount at the point of sale. You never pay the full price and claim money back.
How the number of certificates is worked out
Three things determine it:
- System size in kilowatts. Bigger array, more certificates.
- Your zone. Australia is split into four zones by solar resource. All of Melbourne sits in the same zone, so it does not vary between Epping and Tarneit.
- Deeming years. The scheme credits you for the years of generation remaining until it ends in 2030. This is the part that matters most.
Why it shrinks every year
Because the deeming period counts forward to 2030, it gets one year shorter every 1 January. A system installed this year is credited with fewer years of generation than the same system installed last year, so it attracts fewer certificates and a smaller discount.
This is the single most important thing to understand about the scheme: waiting makes it smaller, not bigger. The step-down is gradual and predictable, so there is no cliff — but there is also no upside to delaying.
Why the dollar value moves
STCs trade on an open market. The price has historically sat somewhat below the $40 clearing-house ceiling, but it moves with supply and demand. That is why two quotes issued in the same week can show different rebate amounts.
Because of this, compare quotes on the final price you pay, not on the advertised rebate. A larger stated rebate against a higher base price is worth nothing.
What you need to qualify
- Panels and inverter from the Clean Energy Council approved product lists.
- Design and installation by an accredited installer.
- A system of 100 kW or less.
- Compliance with AS/NZS 5033 and the relevant wiring rules.
- A grid connection that your distributor has approved.
These are not optional. An installer offering to skip accreditation or use non-approved equipment is offering you a system that cannot claim the rebate and may not be lawful.
What this looks like on your quote
A properly written quote shows the full system price, the STC discount as a separate line, and the balance payable. If yours shows only one number, ask for the breakdown.
Add a worked example using your current pricing A real example — system size, certificate count and resulting discount at today's STC price — is the single most useful thing this page could carry. It needs your actual numbers rather than invented ones.