According to figures released by Energy Victoria, Victorians spend a third of their energy bill on heating, so depending on the property space, ducted heating, and ducted electric heating and cooling can be well and truly worth the upgrade.
Guide to heating, energy savings
Whether users planning to renovate an existing home or user’re investing in a new build, it’s always a good idea to weigh whether gas or electric heating is for users.
Electric heating systems are usually a clear winner, but users may prefer a gas system if user have a smaller space. This article is an excellent guide to understanding each heating mode, their energy consumption, energy costs for both small and large spaces, their greenhouse gas emissions over time, and how to choose for the lifestyle.
Understanding Ducted Heating
What is gas ducted heating, and what is ducted electric heating and cooling? Here is a quick explanation of both and the reasons users may or may not use them to regulate the temperature of the space.
Gas Ducted Heating
Drawing air from inside the home, this is then heated in a gas furnace and blown through ducts to outlets in different areas of the home. A thermostat is near the return air grille and controls the inside temperature. With this in mind, what are the main advantages of gas-ducted heating?
- Reasons to use it? It heats all rooms–or designated rooms from zoning–very quickly. Only heating areas users use to reduce the gas users use overall, and in some cases, different rooms can be controlled with thermostats.
- Reasons not to use it? Air circulation fans use excessive electricity, especially since gas ducted heating runs on natural gas. It is also significantly more expensive to operate than electric reverse cycle systems, and a separate cooling system is needed during warmer days.
Electric Ducted Heating and Cooling
Offering whole-house heating and cooling through one set of ducts instead of just heating alone, electric ducted heating and cooling is located in the roof space.
Like gas ducted heating, heat from outside is pulled into the central unit and blown through duct outlets in the home. Air is returned to the indoor unit to be reheated, and a thermostat controls the indoor temperature. The system doesn’t generate heat directly using an electric heating element; it uses heat pump technology to extract heat from outside air. Arguably, this is the most efficient form of electric heating!
- Why should users use it? A single unit provides enough heating and cooling for the home, so users don’t need to invest in a separate air conditioner. Most systems also allow the home to be split into zones.
- Why wouldn’t users use it? The system’s outdoor compressor can be noisy and conflict with neighbours’ or council regulations. Users may also need three-phase power for larger systems, which can have a high energy consumption. In some cases, this can increase the electricity cost.
Efficiency and Energy Consumption
The energy-efficiency rating is very important, but what is the difference between gas-ducted heating and ducted electric heating and cooling?
Gas-ducted heating
Gas-ducted heating has gas energy labels that allow users to compare different heating options
Gas-ducted heating has gas energy labels that allow users to compare different heating options. The higher the rating, the more efficient it is for the home. Gas heating in homes isn’t the best recommendation in 2024, but if users are considering it, be certain of its energy rating.
If the user plans to build the home, ask about the star rating. It is worth paying more for five-star ratings or higher as the family will save more in the long term. A system with zoning capacity will support these costs.
- R-level or insulation level
Gas ducted systems can also lose energy through their ductwork, so ask the installer about the home’s R-level or insulation level. Always aim for an R-value of 1.0 or higher.
The best temperature to set the heating is 18 to 20 degrees; every 1-degree increase can add 10% to the heating bill. Clean the air filter monthly during winter so it operates effectively, and service the gas furnace at least every two years.
Electric ducted heating and cooling
Since April 2020, new ducted reverse cycle air conditioners with a cooling capacity of less than 30kW have required a Zoned Energy Rating, ideally a high rating, making the system efficient for the home.
Ducted systems need a Zoned Energy Rating but are not required to display it when sold. If users are in doubt, always ask a heating and cooling professional about the rating and if it is best for the lifestyle.
- Types of compressors
A standard compressor will switch on and off depending on thermostat control, and a variable-speed compressor
If a user buys a new system, the user can choose between two types of compressors.
A standard compressor will switch on and off depending on thermostat control, and a variable-speed compressor, known as an inverter, is quieter, more efficient, and runs at a lower speed as soon as the room has reached the desired temperature.
- System zones
Zone the system is great for limiting heat to areas users are using, and this depends on the design of the home and the placement of the return air grille. The stronger the zoning, the more control the user will have over the energy usage. In some cases, there can be energy losses due to ductwork when the air conditioner is operating. The more solid the insulation, the lower the heat losses will be.
Clean the return air grille filter every month, and service the system regularly per manufacturer instructions. If user’s like to learn more, check out this article on reverse cycle vs gas ducted heating and how it can benefit users throughout all seasons.
Installation Costs
The installation cost of the heating and cooling system depends on the number of outlets the user needs, the size of the system, the brand the user chooses to install, and other factors for the home.
Gas ducted heating is generally less expensive to install, with an average cost of $3000 to $7000. Reverse cycle ducted electric heating and cooling averages around $6000 to $12,000.
Common Central Heating Running Costs
Reflecting the gas price increase from 1 February 2023 and the electricity price rise from July 2023
Running costs for gas-ducted heating and ducted electric heating and cooling are some of the most important factors when installing one in the home.
Reflecting the gas price increase from 1 February 2023 and the electricity price rise from July 2023, here is an extensive update on what users can expect. What are the average running costs for both systems and how will the user decide?
Central heating for a small house (100m2)
For unzoned gas ducted heating, a 3-star energy rating has an annual energy cost of $1,704—a 4-star costs $1,528, and a 6-star costs $1,347 for the year.
On the other hand, the ducted reverse cycle air-conditioner (unzoned) is $1,258 annually when using a 1-star system and $899 for the year with a 2-star system.
Central heating for a large house (220m2)
Ducted gas heating systems (unzoned) systems with a 3-star energy rating cost $3,368 annually, 4-star systems cost $3,025, and 6-star systems cost $2,674 annually.
A 1-star ducted reverse cycle air conditioner (unzoned) will cost $2768 for the year, and a 2-star costs $1,977 annually.
Room heating for a small room (12m2)
A gas heater (LPG) with a 3-star energy rating costs $324; a 4.5 star adds up to $289 for the year
Natural gas heating with a 3-star rating averages $223 annually, whereas a 4.5 star costs $213 annually.
A gas heater (LPG) with a 3-star energy rating costs $324; a 4.5 star adds up to $289 for the year.
Room heating for a large room (60m2)
A ducted heating unit (natural gas) with a 3-star energy rating averages $1024 annually, with a 4.5 star averaging $911 annually. Gas heating (LPG) with a 3-star rating is around $1,621, whereas a 4.5-star costs around $1,443 annually.
Reverse cycle air-conditioning with a 1.5 energy rating will cost $626 annually, and 2.5 stars add up to around $469 annually.
Determining hourly heating costs
Users need to understand the system’s listed energy usage, such as MJ/h for gas and kW for electricity, and the tariff rate, which is commonly listed on the electricity bill. Calculate hourly costs for gas ducted heating by multiplying the tariff rate by megajoules per hour for an hourly running cost.
Calculate hourly costs for ducted electric reverse cycle heating and cooling by multiplying the tariff rate by the kilowatts for an hourly running cost.
- Running cost estimate
Accurate costs will depend on how insulated the house is, the heated area, the thermostat
To estimate running costs for a colder climate such as Ballarat and whether it is energy-efficient, multiply these figures by 1.5. For a warmer climate such as Mildura, multiply these figures by 0.8. As for a 5-star home in Melbourne’s climate, multiply the costs by 0.4. 6-star homes should multiply these costs by 0.3.
Keep in mind that this is a guide only, with figures last updated in June 2023. Accurate costs will depend on how insulated the house is, the heated area, the thermostat settings, local climate, energy tariffs, and how insulated the home is.
Carbon Footprint
When installing a heating or cooling indoor or outdoor unit, it’s important to consider its environmental impact. With gas-ducted heating and ducted electricity, what is their carbon footprint?
- Central heating for a small home (100m2): A ducted reverse cycle air-conditioner (unzoned) with a 1-star energy rating produces 18.6 tonnes of greenhouse gas emissions over ten years, whereas a 2 star produces 13.3 GHG emissions. Gas ducted (unzoned) with a 3-star energy rating uses 29.7 GHG emissions over ten years, a 4-star uses 26.6, and a 6-star uses 23.4 GHG.
- Central heating for a large home (220m2): An unzoned ducted reverse-cycle air conditioner with a 1-star energy rating produces an average of 41.0 greenhouse gas emissions every ten years, while a 2-star system produces around 29.3 tonnes. For unzoned gas-ducted heating, a 3-star system produces 65.4 GHG emissions each decade, a 4-star system produces 58.6, and a 6-star rating produces 51.5 tonnes of GHG.
