Home batteries have gone from a niche add-on to one of the most common questions we get. The honest answer to “do I need one?” is that it depends on how your household uses power, what you are trying to achieve, and what your system looks like today. This guide explains how a battery works, when it makes sense, when it does not, and what the current federal support looks like.
The short version
- A battery stores spare solar energy from the day so you can use it in the evening, instead of exporting it to the grid.
- It makes the most sense if you use most of your power after sunset, want some backup, or want to reduce your reliance on the grid.
- It matters less if you are home during the day and already use most of your solar directly.
- The federal Cheaper Home Batteries Program gives an upfront discount on eligible batteries, but the discount steps down every six months.
- Capacity, power rating, backup features and inverter compatibility all matter, not just the kWh number.
How a Home Battery Works
During the day your panels often produce more than your home uses. Without a battery, the surplus is exported to the grid and you receive a feed-in credit from your retailer. With a battery, the surplus is stored first, then used in the evening and overnight, and only then drawn from the grid. The battery is managed automatically, and you can usually watch what it is doing in an app.
The Numbers That Actually Matter
- Usable capacity (kWh). This is the amount of energy you can actually draw from the battery, and it is the figure that matters for both performance and rebates. Nominal capacity can be higher.
- Power rating (kW). This is how much the battery can supply at once. A battery with high capacity but a low power rating may not run several large appliances together.
- Round-trip efficiency. Some energy is lost in charging and discharging, so efficiency tells you how much of what goes in comes back out.
- Warranty and cycle life. Look at how long the warranty lasts and what capacity the manufacturer guarantees at the end of it.
Who Benefits Most From a Battery?
A battery is usually worth serious thought when one or more of these describe you:
- Most of your electricity use happens in the evening and overnight.
- Your feed-in tariff is low compared with what you pay your retailer for power you buy back.
- You want backup power for essentials during an outage.
- You want to take part in a virtual power plant to support the grid.
- You want to use more of your own solar energy rather than export it.
When a Battery May Not Be Worth It
A battery is not automatically right for every home. It may add little if you are home most of the day and already use most of your solar directly, if your system is small, or if your switchboard and roof are not ready for the equipment. Sometimes the better step is to adjust when you run large appliances, or to add panels first. A proper assessment looks at your actual consumption pattern before recommending anything.
Backup Power: What Is and Is Not Covered
A standard solar system switches off in a blackout, with or without a battery. A battery system with a backup function can keep selected circuits running, such as the fridge, lights and internet. Not every battery includes this, and the number of circuits and run time vary. Ask which circuits are covered, how fast the switchover is, and whether the battery can recharge from the panels during a long outage.
AC-Coupled and DC-Coupled Batteries
There are two common ways a battery connects to a solar system. A DC-coupled battery connects through a hybrid inverter and is often chosen with a new system. An AC-coupled battery has its own inverter and connects on the AC side, which is a common way to add storage to an existing system. Our guide to hybrid solar inverters explains the difference in more detail.
Federal Support: The Cheaper Home Batteries Program
The federal Cheaper Home Batteries Program provides an upfront discount through Small-scale Technology Certificates. Under the rules published by the Clean Energy Regulator:
- The battery must be new, installed with a solar system of 100 kW or less, and must not have been commissioned before 1 July 2025.
- It must have a nominal capacity of 5 to 100 kWh, with certificates calculated on the first 50 kWh of usable capacity.
- From 1 May 2026 the support is tiered: the first 14 kWh earns the full factor, 14 to 28 kWh earns 60 percent, and 28 to 50 kWh earns 15 percent.
- The certificate factor steps down every six months through to 2030, so the discount for the same battery shrinks over time.
- The installer must be accredited by Solar Accreditation Australia, the products must be Clean Energy Council approved, and the inverter must be able to join a virtual power plant.
Some states have their own additional support. In Western Australia, for example, the state Residential Battery Scheme can be combined with the federal program: see our WA battery rebate guide. For Tasmania and Victoria, see our guides to the Tasmanian rebates and the Victorian solar rebate.
Safety and Installation
Batteries must be installed by licensed, accredited installers and meet the Australian battery installation standard. Location matters: the battery needs suitable ventilation, protection and clearances, and certain areas of the home are not allowed. We assess this during the site visit so there are no surprises on installation day. See our installation process guide for what happens from assessment to switch-on.
Questions to Ask Before You Choose
- How much usable capacity does this battery have, and what is its power rating?
- Does it include a backup function, and which circuits does it cover?
- Does it work with my existing inverter, or do I need a new one?
- Which rebates apply to this battery today, and where do they appear on the quote?
- What warranty does it carry, and who handles a claim?
Frequently Asked Questions
Do I need a battery if I already have solar?
Not necessarily. A battery makes the most sense if you use most of your power in the evening, want backup, or have a low feed-in tariff. A proper assessment looks at your real usage.
Will my battery work in a blackout?
Only if it has a backup function. A standard solar and battery system without backup switches off when the grid goes down.
Can I add a battery to my existing solar system?
Often yes. Many existing systems can use an AC-coupled battery, while a new system can be designed with a hybrid inverter for DC coupling.
How is the federal battery discount calculated?
It is based on the battery’s usable capacity and a certificate factor that steps down every six months. Since 1 May 2026 it is also tiered by battery size.
What does VPP capable mean?
The inverter can take part in a virtual power plant, where many home batteries support the grid at busy times. It is a condition of the federal battery program.
Does Sunflare Solar install batteries?
Yes. We assess your home, check which rebates apply and handle the paperwork.
Ready for a clear answer for your property? Book a free assessment with Sunflare Solar or call 1300 385 880. We install across Victoria, Tasmania, New South Wales and Western Australia. See the areas we serve.
