Water heating is a significant user of energy. In fact, water heating accounts for the second largest segment of household energy use, after space heating and cooling. More than half of all hot water use is in the bathroom, a third in the laundry and the remainder in the kitchen. Heating water for these activities comprises approximately 25 per cent of household energy use in Australia.

Selecting the right system can have big benefits in terms of household energy costs and meeting household hot water needs – one of life’s essentials. Find out about the types of water heaters you can choose.

Still can’t find what you need? Read our water heating frequently asked questions.

Hot water technologies regulated for energy efficiency

Electric Storage Water Heaters, Gas Storage Water Heaters and Gas instantaneous water heaters must meet Minimum Energy Performance (MEPS) requirements under GEMS. To find out more about MEPS for water heaters check the relevant Australian GEMS determination or the New Zealand regulations (link is external).

Energy efficiency performance requirements are not in place for solar water heaters, heat pump water heaters or electric instantaneous water heaters.

GEMs regulations do not require water heaters sold in Australia to display an Energy Rating Label. The energy label found on gas water heaters is not overseen or administered by the E3 program.

Current Work

The E3 Program regulates hot water heaters for Minimum Energy Performance standards and compliance against those standards.  The program also fosters improved energy efficiency through consumer information, industry capacity building and innovation support.

Guiding objectives for the E3 Hot Water work program are:

  • Develop a unified and comprehensive approach to energy efficiency across hot water technologies
  • Fair, technically sound, and even handed regulation across hot water technologies
  • Provision of reliable and comparable information for consumers and industry
  • Allow meaningful comparisons of energy efficiency across hot water technologies.

Find out more about our current work and how you can contribute your views.

Types of water heaters

What are the available technologies in Australia?

If you are building a new house or replacing an existing hot water heater, you can choose from a range of technologies to suit your home, climate, budget and impact on our environment such as greenhouse gas emissions.

There are two basic types of water heaters on the market – storage and instantaneous (continuous) flow systems. They use a variety of energy sources to heat water including solar, ambient air (air-sourced heat pumps), gas (LPG and natural gas) and electricity. Storage water heaters use an insulated tank to store heated water for use when it is required. All energy sources can be used when operating storage water heaters, depending on what type and configuration of water heater you choose. Instantaneous flow systems heat only the water required and do not use a storage tank, as such they do not suffer the heat losses associated with storage systems. Instantaneous systems can operate on electricity or gas (LPG or natural gas).

The chart below shows the estimated penetration of water heaters in Australian households in 2014. There are a number of different technologies used in the market, with different energy sources and differing levels of use.

At a glance...

Current hot water work

Zoned Energy Rating Label

The energy efficiency and performance of certain appliances can be impacted by where it is installed (location) and other factors such as usage patterns and climate variations, including air temperature, water temperature, frosting, humidity and cloud cover.

A Research Report setting out the methodology and technical elements for a Solar Hot Water ZERL was released in December 2015. Consultation on the report was undertaken between December 2015 and 1 February 2016, and focused on the feasibility and robustness of the technical elements of the proposed approach.  

Investigation of current load profile and load sizes

Investigations undertaken by E3 indicate a range of research identifying differences in the hot water load sizes and draw-down profiles compared to that used in Australian Standards.

EECA Policy Development Roadmap

In conjunction with the E3 Programme, EECA is leading a project to develop a high level policy development roadmap that explores possible new standards and labelling for hot water systems in New Zealand and Australia. EECA has launched an RFP on the Government Electronic Tenders Service (GETS) to procure the services of a consultant to provide technical, economic modelling and policy support on this project. This tender will remain open until 15th January.


Water Heating FAQs

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Search the Registration Database

Use the registration database to view and compare all products that are registered under the GEMS Act.

Registration Database

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Energy Rating Calculator

Compare the energy efficiency of fridges, televisions and computer monitors, clothes washers and dryers, dishwashers, and air conditioners.

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Download the Calculator app

Use the Energy Rating Calcualtor app to compare the energy efficiency and running costs of similar products.


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Useful Resources

Visit the Australian Government's energy.gov.au website for useful information like:


Latest consultation:

15 Dec 2022 AEDT
15 Mar 2023 AEDT