The rebates you can genuinely stack at your postcode, the net outlay after them, and which term — rebates, the gas supply charge, or the energy saving — is really carrying the decision.
Verified 2026-07-24. Every eligibility rule below was checked against the scheme's own published page (linked per line). Amounts marked estimate are certificate-market or retailer-set prices that no scheme publishes as a fixed figure — treat those dollars as indicative and confirm them on your written quote.
Postcode 2000 (NSW)Now gas storageHousehold 3Gas elsewhere yesReplacing now no
positive
Yes, on a normal horizon.
In NSW, switching costs about $2,670 net of rebates and saves about $287/yr — it pays back in about 9.3 years. The decision is carried by the energy saving.
Net outlay after rebates
$2,670
$4,000 installed, less $1,330 rebates
Payback
9.3 yrs
on $287/yr saved · $198 ahead at 10 yrs
The rebate stack
Federal STCs (Small-scale Renewable Energy Scheme) estimatemarket estimate $800–$1,200 (no published figure); modelled at $1,000 source
$1,000
NSW Energy Savings Scheme (ESS) publishedpublished: up to $330 for replacing a gas storage system (scheme range $330–$640) source
$330
Total you actually qualify for
$1,330
What's carrying the decision
Energy saving68% of the case
$287/yr
Rebate stack32% of the case
$133/yr
Gas is still connected for other appliances, so the $383/yr supply charge keeps being paid and is NOT counted as a saving. If hot water is your last gas appliance, disconnecting adds about $383/yr — often more than the energy saving itself.
Modelled as an early switch, so the full net cost is counted. If the old system is already failing, the fair comparison is against a like-for-like replacement ($2,200), which shortens the payback sharply.
Common questions
Can you stack the federal STC rebate with the state hot water rebates?
Yes, but not at their headline maximums. In Victoria the STC discount, Victorian Energy Upgrades and the Solar Victoria hot water rebate all apply — but Solar Victoria pays 50% of what is LEFT after the others, and Victoria publishes a COMBINED cap of $1,560 on VEU + Solar Homes ($1,960 for an eligible locally made unit). Adding the three headline caps together overstates the real total by roughly $600.
Who actually qualifies for the Solar Victoria hot water rebate?
Owner-occupiers of an existing property, with combined owner taxable income under $150,000, a property valued under $3 million, replacing a system at least 3 years old, at an address that has not already had a Solar Homes hot water or battery rebate. Renters and higher earners are excluded — the rebate simply drops out of the stack.
How much is the NSW heat pump hot water rebate?
NSW publishes a typical Energy Savings Scheme incentive of $405–$675 for replacing an existing electric water heater with a heat pump. It is an upfront discount inside the installer quote, not a rebate paid to you, and only installers partnered with an Accredited Certificate Provider can apply it. Larger accelerated discounts run in eligible postcodes until June 2027.
Is a heat pump actually cheaper to run than gas hot water?
On energy alone the saving is real but modest — roughly $290/yr for a typical three-person household. The larger term is usually the gas daily supply charge of about $383/yr, which you only avoid if hot water is your LAST gas appliance. Keep gas for cooking or heating and that saving does not exist, which is why generic "heat pump saves $800/yr" claims often do not apply.
Does South Australia have a heat pump hot water rebate?
REPS (the Retailer Energy Productivity Scheme) covers hot water upgrades, but it is not a fixed-rebate scheme: it obliges retailers to deliver energy-productivity activities and each retailer designs its own offer. There is no published dollar figure, so this tool counts it as $0 rather than inventing one — ask your retailer what actually comes off the price.
Is it worth switching before the old system dies?
Usually not, and that is the comparison most calculators get wrong. If the existing system is already failing you were going to spend around $2,200 on a like-for-like replacement anyway, so only the DIFFERENCE is the real outlay — which can push payback under a year. Switching early means carrying the full net cost instead.