Hot Water Systems

Around 25% of a typical household's energy consumption is dedicated to heating water for various purposes such as the bathroom, kitchen, and laundry. In certain households, this percentage could be significantly higher. With a multitude of options available, selecting the ideal hot water system can be challenging.

In this article, we provide information regarding hot water systems, their functionality, pricing, size, aesthetics, and environmental impact, helping you determine the best fit based on your home, lifestyle, budget and priorities.

"We recognise your desire for a reliable, cost-efficient, and durable hot water system that fits your budget and lifestyle, ensuring a seamless flow in your daily life.."

Points of Consideration

With a multitude of options available, selecting the ideal hot water system can be challenging. Below are a few points to consider when choosing the most suitable system for your home. 

  • What size hot water system is suitable for family’s needs?
  • Should we opt for a hot water tank or a continuous flow system, and what sets them apart?
    • Which one is the most suitable?
  • When comparing gas and electric hot water systems, should we choose a gas storage, gas instantaneous, electric storage, or electric instantaneous system?
    • What is the cost difference between instant and storage hot water systems, and which one is more cost-effective?
    • Which system is more eco-friendly?


In this article, we delve into the advantages and disadvantages of the main hot water system types: the storage tank system and the instantaneous system. 

We also dive into solar hot water systems, providing a greater understanding of the benefits renewable energy sourced systems can have on your long-term budget and the environment.

Energy Sources

Around 25% of a typical household’s energy consumption is dedicated to heating water for various purposes such as the bathroom, kitchen, and laundry. In certain households, this percentage could be significantly higher.

  • Water can be heated using three primary sources:
    • gas, electricity, or the sun (solar energy).
  • There are specific hot water systems tailored to each of these sources.
  • The best system for your home will likely depend on the energy sources accessible at your property or the ones that align with your budget and lifestyle.
  • Consider if natural gas is available at your residence, if you have solar panels, or if your current hot water system is connected to electricity or gas.

“No matter, how rich you are, you can't live without water. Water is Life. Don't Waste It "

Hot Water Storage Tank


Storing water is another factor to differentiate hot water systems.

There are two main types to examine:

  • Storage Tank Hot Water System and,
  • Instantaneous Hot Water System
    • Also referred to as continuous hot water systems, continuous flow hot water systems, instant, or tankless hot water systems.
  • Storage Tank Hot Water System

hot water energy sources

Storage tank water heaters are currently the most commonly used hot water systems in Australia.

These systems utilise an electric element or gas burner to heat water, which is then stored in a tank until required.

When hot water is used in your household for showering, dishwashing and/or laundry, it is extracted directly from the tank.

As hot water is used, cold water enters the tank, necessitating heating during the subsequent cycle.


What size Storage Tank?

The size of the hot water storage tank plays a crucial role in the operation of a storage tank water heater. When choosing a system, it is vital to make sure that it can store enough water to meet your household’s needs for activities like showers, laundry, and kitchen use.

Once the stored water is consumed, the hot water system will not produce more hot water until the next heating cycle, which could be as long as the next day, depending on your system’s setup. For larger families or those with high water usage, opting for bigger tank sizes is advisable.

Storage tank water heaters are offered in electric and gas variants, available in a range of sizes starting from 25-litre units to 400-litre units tailored for larger homes with greater hot water requirements.

With gas being phased out in various Australian states, it is more common to see homeowners using electric systems that are offset by a solar PV system.


Advantages of a Storage Tank Hot Water System:

  • Hot water is readily available when needed since it is stored in the system.
  • Storage tank hot water systems are cost-effective to install and maintain.
  • Electric storage tank water heaters are efficient and safe to operate with the main heating element inside the system.
  • These systems do not need a high flow rate.


Drawbacks of a Storage Tank Hot Water System:

One significant downside of a storage tank water heater is its large physical size, as these systems can hold up to 400 litres of hot water, making them bulky and space-consuming. This can be particularly inconvenient in units or townhouses.

Additional considerations, especially when compared to instantaneous systems, include:

  • Possibility of corrosion, rust, and leaks developing over time (typically manageable with regular maintenance)
  • Energy efficiency and environmental implications
  • Heat loss.

Instantaneous Hot Water System

Instantaneous hot water systems, also referred to as continuous flow hot water systems and tankless hot water heaters, operate without a storage tank to store heated water. They heat water on demand, avoiding the need for storage. These systems come in both gas and electric variations.

Advantages of Instantaneous HWS

One major benefit of an instantaneous hot water system is its ability to provide a continuous supply of hot water, heating water only as needed.

  • These systems can meet sudden spikes in demand beyond normal usage.
  • They offer an unlimited stream of hot water as long as there is a consistent water flow.
  • In contrast, a storage tank hot water system may require time to reheat water in its tank before supplying additional hot water.


Another notable benefit of continuous flow or instantaneous hot water systems is their compact design.

  • As these systems do not store heated water, they are physically smaller compared to storage tank water heaters.
  • This compact size makes them increasingly popular for unit and townhouse installations, with the flexibility to be wall-mounted and kept off the floor.


Moreover, continuous flow hot water systems are relatively easy to maintain.

  • By avoiding water storage, they circumvent issues such as corrosion and leaks commonly found in storage tanks. Additionally, the replacement of parts is relatively straightforward.


Disadvantages of Instantaneous HWS

One drawback of instant or continuous hot water systems is their continuous reliance on external services.

  • In the event of a service outage (water, power, or gas) at your property, your instant hot water system may not be able to provide hot water.
  • Without a tank of preheated water, you will have to wait until the services are restored.


Although they are known as instant hot water systems, these units take a brief moment to heat water compared to storage tanks where hot water is readily available.

Lastly, they can be a little pricier to install than storage tank hot water systems.

The Ideal Hot Water System: Storage or Instantaneous?

The perfect hot water system varies for each individual and their overall household needs.
Below is a comparison outlining the main variances between Storage and Instantaneous systems:

Instant or Storage hot water system
instant or storage hot water system

Environmental Impact

Concerned about the environmental impact of your new hot water system? We hear you loud and clear!

Instantaneous hot water systems are seen as more eco-friendly since they generate fewer greenhouse gas emissions than storage tank systems. 

However, other eco-friendly options which further offset greenhouse gas emissions are available.

These include:

  • solar powered and,
  • heat pump systems.


Transition to Net Zero – Did You Know?

  • Australia has the highest uptake of household solar in the world – more than 3 million homes now have rooftop solar panels. With 12% of energy supplied to the national electricity market coming from solar, Australia the world’s 7th largest producer of solar energy.
  • The Australian Government has made a firm commitment to drive Australia’s transition to net zero.
  • Australia has enshrined in law its targets of reducing greenhouse gas emissions by 43% from 2005 levels by 2030 and net zero by 2050. It Is taking a whole-of-government approach to drive towards those targets including new funding streams and investment in underpinning infrastructure.


Considering a Solar Hot Water System

Solar hot water systems use roof-mounted collectors to capture solar energy.

solar hot water heater

  • After heating the water in either solar panels or evacuated tubes, it is stored in a storage tank.
  • Depending on the system type, tanks can be situated on the roof or at ground level.
  • Solar heating offers energy savings and is often more efficient than gas or electric water heaters.
  • The primary types of solar hot water heaters are split system solar and close coupled.


Why opt for a solar powered system?

  • Enjoy free energy from the sun.
  • Protect yourself from rising energy costs.
  • Save up to 90% on your water heating bills*
  • Offset investment cost with government rebates.
  • Access reliable hot water 24/7.
  • Decrease your household’s carbon footprint.
  • Increase the value of your property.


There are so many reasons to opt for a renewable energy sourced system; however, it is always important to consider your climate zone and whether solar is a suitable investment. 


Considering a Heat Pump Water System

If you’re already using an electric heater and need to switch, you may benefit from using a heat pump water heater.

One major advantage of a heat pump heater is its energy efficiency.

Heat pump water heaters use electricity to move heat from one place to another instead of generating heat directly. Therefore, they can be two to three times more energy efficient than conventional electric resistance water heaters. To move the heat, heat pumps work like a refrigerator in reverse. (

  • If you do get a heat pump water heater, you can look forward to reduced bills and reduced energy usage.
  • The hotter it is where you store your heat pump water heater, the more you’ll be able to save.

In Summary

We understand your need for a reliable and cost-efficient hot water system that fits your budget and lifestyle.  Therefore, seeking expert advice regarding the following is essential:

  • Choosing the right size system.
  • Deciding between a hot water tank or continuous flow system.
  • Comparing gas and electric systems (storage vs instantaneous).
  • Evaluating cost differences between instant and storage systems.
  • Considering the environmental impact of your system and its suitability to the climatic factors of your home’s location. 


And, on a final note:

To ensure safety, reliability and efficiency, it is the law that all hot waters systems must be installed by a licensed technician and registered with your local council.