Hot water heat pumps
Hot water is the second highest source of energy use in an average Canberra home (after heating and cooling). Replacing an existing inefficient system with a hot water heat pump can reduce home energy costs significantly. The ACT is also preparing to transition away from the use of fossil fuel gas by 2045. You can save money by transitioning at a time that is right for you, like when your appliances are due for replacement.
Why it’s important
Most Canberra homes have an old or inefficient water heating system, like a standard electric element hot water system or gas hot water heater, which can contribute to high energy bills.
You can save money and reduce greenhouse gas emissions by installing the most appropriate and efficient water heater for your home, such as a heat pump hot water heater.
A hot water heat pump will heat your water to 60°C as quickly and easily as a traditional hot water system but will use much less energy, potentially lowering your utility bills.
The last step in your transition to an all electric household is to abolish or disconnect your gas connection. While it is an individual household choice, the safest option is for you to abolish your connection. You will save money on your annual supply charge. Learn more about switching off your gas connection.
Selecting a hot water heat pump
Heat pumps are one of the cheapest and most efficient systems to run in the ACT climate. While all heat pump hot water systems work in the same way, there are different options depending on your circumstances. The best set-up for your hot water heat pump will depend on your available outdoor space, plumbing, and budget. The size of the tank also varies, but usually ranges from 150–315 litres for standard sized systems. Larger tanks will be required for homes with more than 5 people to store enough hot water.
All heat pump systems have an outside compressor unit of some kind. When purchasing a heat pump, seek advice from your supplier to help you decide on the best installation location for your outside unit to reduce noise impacts on surrounding neighbours. There are legal limits for the noise levels at the property boundary that are the responsibility of the homeowner. For more information, see installation of air conditioners, evaporative coolers and heat pumps [DOCX 83.8 KB]
Canberra can get very cold in winter. To get the best energy savings and ensure you have hot water all year round, select an electric heat pump that will operate down to at least -5 degrees Celsius on the heat pump alone (some will operate to -15 degrees Celsius). Under -5 degrees Celsius some systems will use an electric element booster.
Other things to consider
Due to Canberra’s extreme winters, it is important to consider selecting from models rated for zone 5 climates with an energy saving of at least 65%. Ask your supplier if your hot water heat pump uses a ‘booster’ during winter to assist with heating the water. This is an electric heating element that the system can use if the outside temperature is less than -5 degrees Celsius. Check that the booster is only used when below -5 degrees Celsius as it can significantly increase your water heating costs if used often.
Hot water heat pumps use well-insulated storage tanks that lose heat very slowly. If they have a timer installed, they can heat water during the afternoon to make the most of the warmer daytime air. Running the system during the day will also allow you to use solar energy if you have a roof top solar system. Talk to your supplier for more information about installing a timer on your heat pump hot water heater.
Home Energy Support Program product requirements
To ensure good value for money, hot water heat pumps under the Home Energy Support Program must meet the following requirements:
- The model of hot water heat pump must be included on the Victorian Energy Upgrades register for ‘Water heater – Heat pump’
Indicative payback periods
Below are some indicative payback periods for upgrading your hot water system from a gas system to a hot water heat-pump.
Hot water — From gas to a hot water heat pump | |||||
Original | Energy Bill Before | Energy Bill After | Saved | System Cost* | Payback |
|---|---|---|---|---|---|
1–2 people | $428 | $144 | $284 | $1,251 | 4.4 years |
3–4 people | $725 | $244 | $481 | $1,736 | 3.84 years |
5–6 people | $1,022 | $344 | $678 | $2,221 | 3.27 years |
* After rebate
* As of September 2022. Subject to change
A generic gas water heating system has been assumed in the calculations. A gas cost of 3c/MJ (inc GST) was used in line with the higher volume residential customer tariff from utility service providers, and 22.4c/kWh in line with average market pricing for the ACT in line with the Australian Energy Market Commission.
The gas heater running cost is based on the average of gas storage and instantaneous gas system. The energy use of heating and storing the water is determined for the storage system, with only the energy use of heating the water chosen for the instant system. Since the calculation was gas energy, the total volume was then calculated against a c/MJ cost for gas to determine the total cost.
Choose the best plan for you
Switching from gas hot water to a hot water heat pump may result in higher electricity usage. It is a good time to make sure that you are on the best electricity plan for your needs. Contact different energy retailers to find out what plans and discounts are available.
We also encourage you to speak to your energy provider about any additional discounts or supports they may have on offer for energy efficient home upgrades.
Contact us
We are here to help. If you need some help with forms or have any questions, please call the ACT Government’s free Sustainable Home Advice Line:
Phone: 1300 141 777
Email: homeenergysupport@act.gov.au
Acknowledgement of Country
We acknowledge the Ngunnawal people as traditional custodians of the ACT and recognise any other people or families with connection to the lands of the ACT and region. We acknowledge and respect their continuing culture and the contribution they make to the life of this city and this region.
