Many homeowners want to know what the return on investment (ROI) is on adding battery storage to their rooftop solar system before purchasing batteries. ie. ‘how long will it take for my battery storage system to pay for itself’? It’s a fair question, given installing a home battery is a significant upfront investment.
While every household’s energy profile is different, there are certain factors that influence the ROI on a home battery system, including battery size, government rebates and whether or not you join a Virtual Power Plant (VPP).
Why adding battery storage to your home solar power system now makes sense
A home battery system lets you store your excess daytime solar energy and use it in the late afternoon/evening/overnight/early morning, when the sun’s not shining. Instead of sending your surplus solar energy to the grid at the time of generation (where you now get paid a pittance); and then buying electricity back in the evening at a much higher price, when solar energy isn’t available, you can power your home from renewable energy 24/7.
Battery storage lets you:
- lower your energy bill and minimising the impact of rising electricity prices.
- be more energy independent so you rely less on the grid.
- access virtual power plants (VPPs) that pay you handsomely for supplying energy back to the grid during peak periods (typically late afternoon/early evening).
By taking advantage of the Federal government rebate and joining a VPP, the credits you receive from being part of a VPP will quickly offset the initial cost of a battery system.
How long before you see a ROI on a battery storage system
The exact payback period varies from household to household because it depends on:
- your household’s daily energy usage
- your solar PV system size
- the size of battery you install
- whether you join a VPP or not
To give you an example of expected savings, Carolyn Lee from The Energy Experts ran her own energy profile through Amber’s new ROI calculator. These are the results with her batteries connected to a VPP provider Amber:
- a 10kWh battery would reduce her energy bill to around $1,475 per year
- a 20kWh battery would return a modest credit of $55 per year
- a 30kWh battery would achieve around $1,337 in credits per year
Caro’s results showed a clear tipping point, which is why she’s chosen 30kWh of battery storage for her own home. Her example highlights how additional storage capacity can have a meaningful impact on your monthly electricity bills. Every household is different, so it’s worth plugging your own usage data into the calculator to see how your numbers stack up. If you’re not comfortable doing this, we can work out the right size battery storage system and the corresponding ROI for you. Get in touch if you’d like our help with this.
In general, most of our clients are able to achieve a 4-5 year payback on their batteries if they:
- receive their 25% discount off the upfront cost of a battery through the Federal Government’s Cheaper Home Battery rebate program
- switch to a VPP provider like Amber, which charges wholesale electricity rates and helps customers get better use out of their batteries..
Does battery size matter?
Having more storage capacity can help you achieve a faster return on investment if you join a VPP.
This isn’t just theory or a way of supersizing clients – recent modelling from Amber, using real-life solar and battery data, shows that larger batteries consistently deliver higher annual savings and credits across all major electricity distributors.
For example, households with a 10kWh battery have seen annual credits ranging from about $47 to $586, depending on their network. At 30kWh, these credits rise to between $692 and $2,365/year. With a 50kWh battery, the annual return increase further to between $1,483 and $3,995.
What does a residential solar battery system cost?
The cost of solar batteries, after deducting the Federal government rebate, can run from around $8,400 for a high-performance 8kWh battery to up to $12,700 for a 24kWh one. You’re looking at about $19,400 for a 48kWh battery. These prices are for a supplied and installed system. This is amazingly cost-effective and it’s all thanks to the Federal government rebate, which came into effect on 1 July 2025.
Costs vary depending on brand. However, we caution buyers against cheaply priced battery brands that may compromise on safety, performance and durability. At The Energy Experts, we supply and install only high-performance batteries that we’re confident offer long-term value.
