Image by Gerd Altmann

Across Australia we’re getting on with electrifying our homes. How do I know? Membership at the Facebook group “My Efficient Electric Home” has topped 33,000 households, with over 300 new members coming in most weeks.

Around Melbourne when my home comfort and energy clients ring up they say, “I want to get my home off gas”. Add to this a lengthening string of announcements informs us of new homes, apartment blocks, and housing developments that will be gas free.

We’ve known since 2015 the cheapest way to heat water and living spaces in Australian homes can be with air-source heat pumps (such as reverse-cycle air conditioners). People like to save money, so they’re switching off the gas. Households can save thousands of dollars a year by abolishing the gas meter and saying good-bye to the gas grid.

Further, we’re more aware of the health impacts of burning stuff in our homes. People don’t want to be poisoned in their homes. They want to breathe easy, so they‘re switching off the gas.

What does the gas industry think about home electrification?

To most of us, the above developments sounds like good progress. Save money, stay healthy, decarbonise.

But to little surprise, gas companies still think it’s a bad idea. If the trend continues, there’ll be no need for many parts of the gas industry. Pipes leaking greenhouse gases down our suburban streets can become a thing of the past.

Fighting for their survival, the gas industry recently launched some defensive strategies.

One strategy is to say we cannot, should not, must not, electrify our homes. Why not? Because it would ruin their business sure, but also because they claim it would crash the electricity grid.

Imagine all those homes, requiring electricity to run the heat pumps and induction cooktops on a cold winter night. That must require a lot of electricity. There is no way that could be managed, so you know what happens next… BLACKOUTS! 

It’s an interesting hypothesis: home electrification crashing the electricity grid mid-winter. Certainly, we need to look at all the impacts of widespread home electrification, such as:

  • ongoing population and economic growth
  • hotter and hotter summers with greater reliance on cooling systems
  • more and more solar panels on our rooftops
  • batteries in homes and around our suburbs
  • electric cars plugging in 

My view is that home electrification won’t lead to the scary blackouts. Here are some points to consider, using as an example the big gas burning state of Victoria.

1. Thus far, Victoria has seen peak electricity demand in summer, not winter

The highest-ever peak-moment Victorian electricity supply/demand occurred at 3pm on 29 January 2009, at a level of 10.6 giga-watts (GW). Ambient temperature hit 43 degrees Celsius that day. It was a record-breaking hot summer and peak demand occurred not many days before the infamous Black Saturday. 

Whereas during the depths of winter 2021, Victorian electricity supply/demand hit a high of 8 GW at around 6:30pm 20 July 2021, only 75 per cent of the 2009 peak. 

Peak winter electricity demand has room to grow by 2.6 GW before it reaches the record-setting level seen back in 2009. Interestingly this headroom allows average growth in electricity demand of about one kilowatt for each of Victoria’s 2.5 million homes. 

Of added seasonal benefit, electricity supply specialists know that electrical equipment finds it easier to transmit electricity when it’s cooler outdoors, in other words, in winter.

It won’t be a bad thing when we increase the productivity of our electricity-supply infrastructure by using it at a higher level all year round, rather than just during a few hot hours each decade. 

2. Efficient modern air cons don’t use that much electricity in winter

The above-mentioned one kilowatt of electricity applied to a reverse-cycle airconditioner can result in five kilowatts of heat being added to a home, which is a significant amount of heat. 

Airconditioners have had a reputation for being inefficient beasts, and indeed in days gone by they were. But today, even the worst air con available on the Australian market is more efficient than the best one was 20 years ago. We need to adjust our thinking and appreciate the benefits of heating with air cons (heat pumps).

3. Victorians often make the wrong economic home-heating choice

Because we have spent decades demonising the use of air cons for summer cooling, constantly raising the spectres of grid blackouts and high electricity bills, Victorians often make the wrong winter heating choices. 

I have observed that some Victorian homes may have up to three heating options available, with the householder opting to use an electric-resistive panel heater (at up to five times the electricity use and cost) or gas heating (at up to 3x the cost), while the cheapest option, the reverse-cycle air con, sits idle on the wall, waiting to be sparingly used next summer.  

Clearly, if we can educate householders that an air con can use 1/5th the electricity of an electric-resistive heater, electricity demand for some homes will fall rather than go up.

4. Gas heating uses a surprisingly large amount of electricity

Here’s an overlooked fact: ducted gas heating uses electricity, and a lot of it! Sustainability Victoria researchers examined existing housing stock. One of their biggest findings was just how much electricity gas heating can use… for the air circulation fan. 

The 500 or more watts of electrical power that a ducted gas heating system may use, let’s instead use it to drive a reverse cycle air con. That will provide a lot of heat while no additional electricity is drawn from the grid…but with zero gas use. 

5. Electrifying homes doesn’t have to result in increased electricity use

At My Efficient Electric Home there are many case of Australians electrifying their homes but then finding no noticeable increase in their electricity use. How can this be? 

Constantly we see replacement of old inefficient electrical equipment (for instance halogen downlights, vented clothes dryers, plasma TV’s, old refrigerators) with appliances using one-half, one-third, or even one-tenth as much electricity as the old equipment. When these upgrades occur at the same time as switching off gas appliances in favour of heat pumps, a homeowner can see no increase in electricity use. 

6. Our average homes are poor for comfort and energy performance, but are improving

It’s well known that Australian homes are often uncomfortable and poor thermal performers. But they’re getting better. Minimum Victorian standards (6 star NatHERS) now require that a new-build home use 30 per cent or less energy (a square metre of floorspace) versus a current average home. The building standard is expected to further improve to 7 star with energy use falling to only 20 per cent of average.   

As the thermal performance of new and existing homes is improved with draught sealing, insulation, and better windows and window treatments, this ensures the impact of home electrification on the electricity grid can be small.

7. Electricity “demand management” techniques can be applied in winter and summer 

In recent years, the owners and managers of our electricity grids have made good strides in managing peak summer demands to ensure reliable electricity at the most critical times. “Demand-response” techniques are one such mechanism. But these aren’t just for summer use. If we eventually see wintertime electricity demand approach summer levels, demand management methods will be used in winter too.    

8. Electric vehicles can use more electricity than homes, but can supply peak demand

Lobbyists can be conflicted. If their job is to represent the electricity suppliers, they’re happy to suggest we can readily fuel-switch from petrol to electricity in our cars. But if the same lobbyist represents gas suppliers, they’ll say it’s impossible to fuel-switch from gas to electricity in our homes. This is peculiar because often a car uses far more electricity than a house.

The roll-out of electric vehicles will massively impact the way electricity is supplied. The impact of home electrification will be less significant. Intriguingly, we are likely to use the large batteries present in electric vehicles to sometimes power our homes (“vehicle-to-grid”). This is one more tool we can use to manage future peak electricity demands.

Electrification obviates expansion of gas supply infrastructure

Finally, it’s worth pointing out while the gas industry expresses concerns about winter electricity demand, gas users will be paying more for the expansion of winter gas supply and also for the gas industry dabbling with expensive hydrogen. Electrifying our homes means we can do without all that extra expense.    

Regardless of what the gas industry says, large economic benefits are driving Australians to electrify their homes… now! 

The possibility that electricity demand may increase in winter deserves independent and detailed analysis. But it’s unlikely to be an unmanageable problem. Let’s ensure more and more households can enjoy the benefits of electrification as we accelerate away from increasingly-deadly fossil fuels.  


Tim Forcey is a home energy consultant and researcher. Join the My Efficient Electric Home Facebook group.

Join the Conversation

7

Your email address will not be published. Required fields are marked *

  1. I want to get our home off gas, but with asthmatic family members am not so keen on using our air con for heating. Is there any way hydronic heating can be powered by electricity?

  2. Given the new building code is likely to allow solar to offset against the new stringent requirements, the days of standard gas connections to new homes will soon be over.

  3. The content of this article would be solid viewing in a news article between 5 & 7.30 pm on all the stations.
    Lots or people would benefit.
    Tradespeople are needing more current information about energy systems – many plumbers are still promoting gas connections.