Heat Pump Hot Water Systems — How They Work, 2026 Cost & Rebates
A heat pump hot water system works like a fridge in reverse — it moves warmth from the outside air into your tank instead of burning gas or running an element. That uses a third of the electricity of a standard electric tank, and after federal STCs plus state rebates a system can cost as little as $33 out of pocket in VIC or NSW ($3,800–$5,500 installed before rebates).
How a heat pump hot water system works
Rather than generating heat with an electric element or gas flame, a heat pump extracts warmth from the outside air (like a reverse-cycle air conditioner in reverse) and transfers it into the water tank. Because it moves heat rather than making it, it delivers 3–5 kWh of hot water for every 1 kWh of electricity — a coefficient of performance (COP) of 3–5.
CO2-refrigerant units (Reclaim, Sanden) hold their COP well below 5°C, making them the go-to for climate zones 5–8 (Melbourne, Canberra, Hobart, Alpine).
2026 cost by tank size
| Tank size | Household | Installed price | After STCs | After state rebate |
|---|---|---|---|---|
| 170L | 1–2 people | $3,200–$4,200 | $2,400–$3,300 | $33–$1,800 |
| 270–280L | 3–4 people | $3,800–$5,500 | $2,900–$4,500 | $33–$2,500 |
| 315L | 4–5 people | $4,400–$6,200 | $3,400–$5,100 | $500–$3,000 |
| 400L+ | 5+ / large | $5,500–$8,500 | $4,400–$7,300 | $1,500–$5,000 |
Prices exclude non-standard installs (concrete pad, long pipe runs, upgrade from gas). VIC/NSW low-income households can access $33 units through approved retailers.
State-by-state rebates in 2026
Federal — STCs
Small-scale Technology Certificates apply nationwide. A 270L unit generates 25–35 STCs, worth roughly $800–$1,100 assigned upfront by the installer.
Victoria — HWSS / VEU
Up to $1,000 additional discount through the Home Heating and Cooling Upgrades program. Some VEU installers advertise $33 installed for low-income households.
NSW — ESS
Energy Savings Scheme discounts through accredited providers frequently deliver $0–$500 units for eligible homes replacing electric tanks.
SA — REPS
Retailer Energy Productivity Scheme discounts vary by retailer — typically $500–$1,500 off installed price on top of STCs.
ACT — SHS
Sustainable Household Scheme offers 0% interest loans up to $15,000 for heat pumps, batteries, and induction — you cover the balance interest-free over 10 years.
QLD / WA / TAS / NT
STCs only at present — no dedicated state heat pump rebate. Watch for the federal Cheaper Home Batteries program crossovers in 2026.
Running cost vs electric & gas (4-person household)
| System | Annual energy | Annual cost | 10-year cost |
|---|---|---|---|
| Heat pump (COP 4) | ~900 kWh | $250–$400 | $2,500–$4,000 |
| Heat pump + solar timer | ~900 kWh (90% solar) | $50–$120 | $500–$1,200 |
| Instantaneous gas | ~18 GJ | $700–$900 | $7,000–$9,000 |
| Electric storage | ~3,500 kWh | $900–$1,300 | $9,000–$13,000 |
Best brands shortlist (2026)
- Reclaim Energy CO2 — Australian-assembled, 15-year tank warranty, best-in-class cold-climate COP. ~$5,500 installed.
- Sanden Eco Plus — CO2 refrigerant, very quiet split system, 15-year tank warranty. Premium price.
- iStore 270L — mid-price sweet spot, widest installer network, 10-year tank warranty. Popular VIC / NSW rebate pick.
- Rheem Ambiheat / Reclaim Ambient — integrated tank, easy swap from an old electric unit.
- Chromagen Midea — the entry point for state-rebate installs; solid performance in zones 2–4.
Next step: get quotes from a certified installer
The right unit depends on climate zone, existing plumbing, and which rebates you qualify for. We'll match you with vetted local installers who apply all federal + state rebates upfront.
Related guides
Hot Water Systems Australia
Compare heat pump vs solar vs gas vs electric.
Solar Hot Water
Roof-mounted evacuated tube & flat-plate systems.
Cheaper Home Batteries Program
Federal battery rebate — pair with a heat pump for max solar self-consumption.
Is Gas Being Phased Out in Australia?
What the shift to efficient electric means for hot water, heating and cooking.
Whole of Home Assessment
How hot water fits into your NCC 2022 energy budget.