More than 400,000 batteries have been installed under the cheaper home batteries scheme. Here’s how to get the best bang for your buck
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If Australians love solar, they are head over heels for home batteries. More than 400,000 batteries have been installed under the government’s subsidy scheme.
Here’s what you need to consider if you’re looking at getting one installed.
The cheaper home batteries program was originally designed to encourage people to install systems that were too big for what they actually needed. In December, the government announced it would create a tiered scheme to support households to pick systems better tailored to their needs.
In changes to the scheme from May, all battery systems will receive the full base subsidy on the first 14 kilowatt hours (kWh) of usable capacity. Systems that go above 14kWh will get 60% of the subsidy, up to 28kWh. Anything between 28 and 50kWh will be subsidised at a rate of 15%.
The discount will then be slowly reduced every six months until 2030.
Tim Forcey, a home comfort and energy adviser, researcher and author, says there is no need to rush and that it may be worth households investigating other measures first.
The first step is to improve energy efficiency, with better insulation in the roof and walls, draught-proofing, window coverings and double-glazed windows. These measures mean that, as you move to the next step to electrify your home, you will get far more value from your appliances.
Installing split-cycle air conditioning that uses a heat pump to both cool and heat your home, replacing gas cooktops with induction and swapping out a gas water heater with electric are all good next steps.
“Now you’ve got an all-electric home, so you’ve got a better chance to get actual value out of a battery,” Forcey says. “Having a big battery that you’re using to power a leaky house is not an efficient or effective use.”
That depends. There are many reasons to invest in a battery, and sometimes good reasons not to.
“Every household is quite different,” UNSW’s Dr Dylan McConnell says. “Bigger is not always better from a return on investment perspective, or value perspective.”
The first question is whether you have solar. If you don’t have solar, getting a home battery can still be useful, particularly if you are in an area prone to blackouts or disasters and want to be more resilient.
Batteries do their best work when paired with solar. The Smart Energy Council’s chief strategy officer, Nigel Morris, says that as the biggest cost associated with solar is the initial installation fee, it is a good idea to maximise your generating capacity.
“The best bang for your buck, and the best bang for the environment, is to put on as much solar as you can. No one ever said: ‘Damn, I added too much solar’,” Morris says.
There is no reason to replace an older solar system if it is meeting your needs, but it may be time for an upgrade if your electricity use has grown. For those who are investing in solar for the first time, Morris says going bigger off the bat can help future-proof, particularly for households looking to buy an EV, add other appliances or have children.
“As you start to electrify your home, it’s likely your home will increase consumption,” Morris says. “For example, an electric vehicle adds a significant amount of load. That’s a really important factor in system design. Many people will want or need to charge, to some degree, overnight, so storage becomes really crucial.”
“The basic idea is straight forward: use the sun to charge the battery, and then use the battery at night to run the house,” Forcey says. “During the peak hours, especially during the five-to-nine peak times, that’s when the grid will be most stressed and most expensive.”
With the average system size since December roughly 32kWh, and the average daily household use roughly between 15 kWh and 20 kWh, McConnell says most systems will be more than enough for what’s needed.
Choosing a reputable installer is crucial. It is tempting to look for a cheaper option but the more significant factor is quality of work and reputation. An installer should be willing to answer your questions, take time to understand your circumstances, and be willing to teach you how the system works so you can make changes or detect problems.
Attention to detail is especially important for safety, Morris says. A badly placed battery may be at risk of being hit when entering a tight-fitting garage, or crunched if someone accidentally hits the accelerator instead of the brake.
Forcey has heard stories of people whose batteries were installed incorrectly, so they drew power during the most expensive times and discharged at the cheapest.
Unless you are going fully off-grid, which can be very expensive, make sure to read your existing electricity plan to understand how you are being charged, and how to set your battery to take advantage.
From 1 July, for example, some providers will begin offering free electricity in the middle of the day between 11am and 2pm. A home battery could be programmed to charge during this period for use later in the evening. Other providers may offer EV-specific charging plans.

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