Heat-Pump Hot Water Rebates in 2026: How STCs Cut the Price

A heat-pump hot water system is the one upgrade that quietly eats a big slice of the average power bill — water heating is often the second-biggest load in an all-electric home. The federal Small-scale Renewable Energy Scheme (SRES) rewards swapping an old electric or gas unit for a heat pump by issuing certificates that your installer trades for an upfront discount. Here's exactly how that works in 2026, and the honest question of whether it pays for your place.

How the STC discount actually works

Heat-pump (and solar) hot water systems are eligible to create Small-scale Technology Certificates (STCs) under the SRES, a national scheme run by the Clean Energy Regulator. The number of certificates a given model earns depends on the energy it's modelled to displace and your climate zone — a unit in warmer northern zones typically generates more certificates than the same unit in a cold southern zone.

In practice, almost nobody sells the certificates themselves. The installer or retailer registers the system, claims the STCs, and subtracts their value from the price you pay. You see a single "price after STC" number on the quote. The certificate value floats with the market, so the discount isn't a fixed dollar figure — it moves.

What changes the size of your discount

• Climate zone: warmer zones model more displaced energy, so more STCs and a bigger discount.
• The specific model: different units are assigned different certificate counts — two heat pumps at the same list price can land at very different after-STC prices.
• The STC spot price: this is a traded market. A lower certificate price means a smaller discount, even if nothing else changes.
• Installer margin: the STC saving is real, but how much of it reaches you depends on the quote. Compare the final after-STC price, not the headline rebate.

STCs stack with any state hot-water rebate that may exist where you live. State schemes vary and some states have none — confirm what applies at your address before assuming two discounts apply.

Does a heat pump actually pay? The honest version

A heat pump uses roughly a quarter to a third of the electricity of an old resistive element to deliver the same hot water. If you're replacing a tired electric-element tank, the running-cost saving is usually substantial and the case is strong — especially after the STC discount. But the maths isn't automatic for everyone:

• You already run cheap off-peak electric: if your old tank heats overnight on a controlled-load tariff that's genuinely cheap, your running cost is already low and the payback on a new heat pump stretches out.
• You have solar and a diverter: a standard electric tank soaking up your own midday solar export (worth only a few cents per kWh as a feed-in tariff) can be close to free to run. A heat pump still wins on efficiency, but the saving is smaller than the brochure implies.
• Cold climate and poor siting: heat pumps work harder in cold zones, and some have a fan that makes noise — placement next to a bedroom window can be a real-world problem.
• Gas hot water that's working fine: the economics depend on your gas and electricity rates; it's a genuine calculation, not a given.

So the discount lowers the entry price, but payback is driven by what you're replacing and how you'd run the new unit. That's the number worth modelling before you commit.

Making the discount work harder

If you also have (or are adding) solar, a heat pump on a timer that runs during the middle of the day turns low-value exported solar into stored hot water — often a better use of that energy than the feed-in tariff, which our pack puts in a typical range of just 3–10 c/kWh and which has trended down for years. A smart timer or built-in solar-soak mode is worth asking about.

From 1 July 2026 the federal Solar Sharer offer provides a free-power window of 11am–2pm (up to a 24 kWh daily cap) through participating retailers on eligible plans — if that's available where you are, scheduling your heat pump into that window can cut running costs even without rooftop solar. It requires a smart meter and an opt-in plan, and availability varies by retailer and state, so confirm it before relying on it.

Before you sign a quote

• Get the after-STC price in writing and check it against at least one other model.
• Ask how many STCs the quote assumes — and whether that reflects your climate zone.
• Check your current hot-water running cost (tariff and tank type) so you can estimate real payback, not just the sticker saving.
• Confirm any state hot-water rebate separately — it may or may not exist where you live.

We don't sell or install heat pumps, and we don't take a cut of any STC. That's the point: we'll model your actual hot-water bill and tell you honestly whether a heat pump pays for your household — 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.