Is a Gas Hot Water System the Best Option?

When you’re choosing a hot water system you have to question what the best and most economical form of power is for your household.

There’s a range of options when it comes to heating water, including electric, solar, heat pump and gas hot water systems. All provide reliable hot water for family homes.

So, if you have access to natural gas, is it also the most efficient way to deliver hot water at home? Here we look at the different types of gas hot water systems on the market and how they compare to the alternatives.

When it comes to choosing a gas hot water system, there are two main types – continuous flow (or instantaneous) and storage tank. Both of these hot water systems run on natural gas, although they can also run on LPG (liquefied petroleum gas).

If you have solar panels, you can also choose to install a gas-boosted hot water system. Continuous flow, storage tank units and gas-boosted systems all have their benefits, which are worth considering here.

Continuous Flow Gas Hot Water

An instantaneous gas hot water system is a wall-mounted unit. Water is heated as it moves through internal pipes, only as you need it. As such, continuous flow units are a cost-effective way to heat water, providing a steady flow and ideal for smaller households and anyone who’s energy conscious.

A gas instant hot water system is energy efficient and the savings are considerable compared to an electric storage tank hot water system. Here are some of the other advantages of a gas instant hot water system:

• They last longer – While a storage tank unit will last about 10 years, instantaneous systems last up to 20 years.
• Easy to operate – For complete temperature control, install thermostats at each point of use.
• Easy to maintain – Because there’s no storage tank, which can rust and leak, a continuous flow system is easy to keep in peak condition.
• Save on space – A small wall-mounted unit saves you plenty of space compared to a large hot water tank.

A gas storage tank takes up more space but does provide a larger supply of hot water for bigger households. Much like a continuous flow gas hot water system, it’s an energy efficient alternative to electric hot water systems (particularly storage tank models).

Gas storage tank units, like continuous flow systems, are also environmentally friendly, producing low greenhouse gas emissions.

Gas-Boosted Solar Hot Water

This type of gas hot water system works by automatically transferring the power supply from solar to natural gas when the tank temperature goes below a predetermined threshold. This is so householders can set a thermostat and let the gas hot water unit handle the rest of the work.

Gas-boosted solar hot water systems are among the most economically and environmentally friendly ways to heat your water. Natural gas-boosted systems produce significantly fewer greenhouse gases than electricity fed systems. On the negative side, they are more expensive to set up than an electric fed system.

So, how do gas hot water systems stack up against the likes of electric systems, electric fed solar power and heat pump systems? It’s not an easy question to answer.

As previously stated, a gas hot water system will save you money on energy bills compared to a standard electric system. But there are advantages to using electricity:

• Solar panels – If you’ve got solar panels, you can power your hot water system using this renewable energy source. By sending power back to the grid, you will save on energy bills.
• Energy efficient – If you’re using solar power it’s more energy efficient than a standard gas system. However, during winter months when there’s less sunlight you may need to use mains power.
• Lower upfront costs – Electric hot water systems are cheaper to buy and install than a gas system (but more expensive to run).
• Heat pump system – A heat pump system uses heat from outside the unit and transfers it to the water inside the tank. They are more energy efficient than conventional electric water heaters and are environmentally friendly. These are available as storage or continuous flow systems.

When examining the alternatives in hot water systems, a number of factors need to be considered. These factors include:

• The climate you live in
• Number of people in the household
• How energy efficient the system is (star rating)
• How often you use hot water
• Energy tariffs

Ultimately it comes down to what works best for your household, particularly when it comes to power bills. Based on a study from December 2021 (by Sustainability Victoria), here’s how the different systems compare for a household of four people (using 150 litres per day) over a period of a year.

• Solar natural gas boosted – $75
• Solar LPG gas boosted – $155
• Heat pump – $258 (average of peak and non-peak tariff)
• Natural gas (instant) – $267
• Solar electric boosted – $297 (average of peak and non-peak tariff)
• Natural gas (storage) – $302
• LPG (instant) – $610
• LPG (storage) – $720
• Electric (instant) – $805
• Electric (storage) – $815 (average of peak and non-peak tariff)

All figures are an average between two systems with different energy star ratings, except for the electric systems.

In conclusion, it’s clear that natural gas comes out ahead economically when it comes to hot water systems, particularly in combination with solar power.

Continuous flow systems also rank higher than their storage system counterparts, so that’s another factor to consider if you’re planning to upgrade.

For energy efficiency, reliability, the environment and your household budget, gas hot water might be the way to go.

Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.