Heat-Pump Hot Water Rebates in 2026: How STCs Work

If you're replacing a hot water system in 2026, you've probably seen ads for a heat-pump unit "from a few hundred dollars installed". That headline price exists because of a federal certificate scheme — not a cash rebate you claim later, but a discount applied at the point of sale. Here's exactly how it works, and the honest question most installers won't ask you: whether switching to a heat pump is actually the right call for your household.

What the federal STC discount actually is

Heat-pump (and solar) hot water systems are eligible under the Small-scale Renewable Energy Scheme (STCs) — a national program administered by the Clean Energy Regulator. When you install an eligible unit, it creates a number of Small-scale Technology Certificates (STCs) based on how much greenhouse-friendly water heating it's expected to deliver over its lifetime.

In practice you almost never touch the certificates yourself. The installer assigns them to a trader, and that value is taken straight off your invoice. That's why you see a "price after STCs" rather than a rebate you apply for. It's the same mechanism that sits behind the "after STC" pricing on rooftop solar.

How much comes off the price?

Honest answer: our knowledge pack confirms heat-pump hot water is STC-eligible nationally, but it does not list a specific dollar value or a specific "installed after rebate" price for a heat-pump unit — so we won't invent one. The number of certificates (and therefore the discount) depends on the unit's rated capacity, your climate zone, and the STC spot price at the time of install, which moves.

What we can tell you plainly:

• The discount is applied upfront at purchase, not refunded later.
• The dollar value changes as the STC price and certificate deeming rules change — always ask the installer to itemise the STC value on the quote so you can see the pre- and post-certificate price.
• Confirm the current certificate value and any state top-up before you commit — don't rely on a headline figure from an ad.

Whether a heat pump actually pays — the catch

This is where independent advice matters. A heat-pump hot water system uses roughly a third of the electricity of an old electric-resistance (element) tank. If you're replacing a tired electric-storage unit, the running-cost saving is genuinely significant and the STC-discounted price makes the switch attractive.

But the maths is very different in other situations:

• You're on cheap controlled-load (off-peak) electric hot water. Your current running cost may already be low. A heat pump still saves energy, but the dollar gap shrinks — and the payback stretches out.
• You're replacing gas hot water. Whether a heat pump wins depends on your gas rate versus electricity rate, and on daily supply charges — sometimes it does, sometimes it barely moves the needle.
• You have (or are getting) solar. A heat pump that runs in the middle of the day can soak up cheap or exported solar instead of earning a low feed-in tariff. Feed-in rates are typically modest and falling, so self-consuming your own generation to heat water is often better value than exporting it. That changes the sums in the heat pump's favour — but only if the unit can be timed to run when the sun's up.

Heat pumps also have real-world quirks: they can be noisier than a silent tank (a compressor, like a fridge or air-con), they perform less efficiently in very cold climates, and cheaper units can have shorter lifespans that erode the saving. None of that is a reason to avoid them — it's a reason to size and site the unit properly.

Making the numbers work for your house

Before you buy, the figures worth pinning down are:

• What you're replacing (element electric, controlled-load electric, or gas) and its current annual running cost from your bill.
• Your electricity tariff — Time-of-Use peak periods are commonly around 2–8pm; running a heat pump in peak is far dearer than running it midday or off-peak.
• Whether you have solar, and whether a timer can shift heating into your generation window.
• The itemised STC discount on the quote, plus any state-specific hot-water incentive confirmed as current for your state.

Put those together and you get a real payback figure for your home — not a generic one from a brochure.

We don't sell or install hot water systems, and we never will. That's the point: our only job is to run your actual bill and tariff through the numbers and tell you straight whether a heat pump pays for you — or whether your current setup is already cheap enough to leave alone.

Figures in this guide are current at the date of publication and indicative only — rebate and certificate values change over time (federal battery certificates step down each January and July), and state schemes are amended often. Confirm the current numbers for your situation before you commit. This is general information, not personal financial advice.