When should you replace your old gas appliances with electric

      So you have come to the realisation that it makes more financial sense to replace your existing gas appliances (namely your cook-top, central heater and gas hot water) with their more efficient electric equivalents (namely an induction cook-top, a Daikin US7 space heater and a Sanden heat pump hot water system) but the question you ask yourself is, when should I take the plunge, when should I replace my existing (and still functional) gas services and go all-electric?

Of course that does depend on your personal financial situation but there are also a couple of other factors to consider when deciding when it is the right time to ditch gas and go all-electric.

Factor one:  The age of your gas appliances

The first question that springs to mind would be ok, so how long can I expect my gas appliances to last?  A good estimate is: Gas heaters central/wall mounted etc last about 15-20 years, gas hot water (with storage tank) 10-12 years and gas cook-tops 15-20 years. Whether you reach or exceed the upper end of the range or only get to the bottom end of the range without issues clearly depends on your usage patterns and how often you maintain your appliances.  Gas appliances are supposed to be serviced by a licensed gas fitter every 2 years (at a cost of around $150-$300) and of course the older they are the more maintenance they are likely to require.  Note: attempting to service gas appliances yourself or using a fly-by-night tradie might invalidate your home insurance.

Given that going all-electric costs money, you might be tempted to think it makes more sense to run your current gas appliances into the ground first then replace them as they break, but does that really add up?  Given that older appliances need to be maintained more often your maintenance bill might start to escalate improving the case for replacement.  The other factor to consider is that going all-electric means you will save money in operation from the day of the switch; as all-electric homes are about 66% cheaper to run than gas homes, not to mention the fact you can get rid of the $260 ish a year gas supply charge.  Of course if you have solar on your roof your overall energy bill could be $0.

But those are just the financial aspects of not replacing gas appliances, what about some of the more serious issues with old gas appliances, like safety. 

The worst problem with old gas heaters (in particular open-flued gas heaters where the products of combustion spill into the room being heated) is the potential for incomplete combustion which produces carbon monoxide, which can kill.  This is a rare but very dangerous problem so if you are thinking about hanging onto and old gas heater you should invest in a carbon monoxide alarm (you can get them at Bunnings) to protect yourself. However, even if carbon monoxide doesn't poison you it is not good for you and can negatively affect your health and impair your thinking if indoor levels get too high.   Other potential problems include gas leaks (that nagging feeling you left the gas on when you left the house) or the flame going out (this is a particular issue with gas hot water pilot lights if you have an interruption to your supply e.g. the Longford explosion in Victoria)

Factor two:  The cost of gas is increasing

In the good old days of gas, gas was so cheap it was nearly free (about $2/GJ) it was actually going to be flared as an unwanted by-product of oil drilling but someone had the good sense to hook it up to a reticulated gas network to get some use out of it.  But the days of cheap gas are long gone.  You see, a few years ago the gas companies worked out that they could make more money exporting the gas than selling it domestically, which instantly linked the gas price to the overseas market price (which is much higher). Ever since that happened the cost of gas has risen significantly, in fact so much gas is now exported that AEMO (gas and electricity planner) admits that it doesn't know where it will get domestic gas supplies in 2025, with some speculating that floating gas terminals might be needed for the domestic market (say hello to $20/GJ gas if that happens).

Predicted wholesale gas price for all East Australian states, 2018-2038


Predicted wholesale gas price for all East Australian states, 2018-2038

Source: AEMO ESOO 2019


It is likely that these price rises are an underestimate (we were told that the electricity market would result in lower electricity prices).

Factor three:  All-electric homes are safer and more comfortable

As mentioned gas services have some intrinsic safety issue that electric services do not have, they come with the risk of carbon monoxide, gas leaks (and explosion) and kitchen fires.  Induction cook-tops also are safer in that they have no open flame (which regularly sets fire to loose sleeves, tea towels, grease, plastic pot handles etc) and will not even operate unless the correct pot or pan is on the hob. All electric homes are more comfortable, especially given the US7's ability to alter humidity and provide fresh, filtered air, something a gas central heater will never be able to do.  What price do you put on safety and comfort?  Ultimately that is up to the individual but it is a factor to consider and at least a tie breaker in favour of electric services.


So in summary when is the best time to replace your gas appliances?  If your gas appliances are old (i.e. more than 50% of the way through their service life) and you are a heavy gas user it probably makes sense to replace them right away (to avoid rising maintenance and usage costs) and to avoid serious price hikes around 2025. If they are brand new you probably want to replace them around or before 2025 (again to avoid spikes in the price of gas) and if you suspect your appliances are in any way unsafe, the best time to replace them is yesterday!