So your solar panels have been doing their thing for a while now, but lately you've been thinking: what if I could store all that excess power I'm generating during the day and use it in the evening instead of buying expensive electricity from the grid?
Enter the solar battery retrofit. It's not as complicated as it might sound, and with battery prices dropping and electricity bills climbing, the numbers are starting to make a lot more sense for Australian households.
Here's everything you need to know about adding a battery to your existing solar system, plus how to make sure you get the most out of your investment.
Why add a battery to your solar system?
If you've had solar panels for a while, you've probably noticed that you generate the most power during the day when you might not be home to use it. Without a battery, that excess energy gets exported back to the grid - often at a pretty low feed-in tariff rate.
A solar battery lets you store that daytime solar energy and use it when you actually need it - like in the evening when you're cooking dinner, or overnight when your panels aren't generating anything.
But there's more to it than just storing power:
Better use of your solar investment - Instead of selling excess solar back to the grid for cents, you can use it yourself and avoid paying peak electricity rates
Energy independence - Less reliance on the grid means more control over your energy costs, especially as electricity prices continue to rise
Backup power - Many battery systems can provide backup power during blackouts (though this usually requires additional equipment)
Supporting renewables - By storing and using more solar energy, you're helping reduce pressure on the grid and supporting Australia's transition to clean energy
Can you add a battery to any solar system?
The short answer is: usually, yes. Most existing solar systems can be retrofitted with a battery, but the approach depends on what type of solar setup you already have.
Here are the main scenarios:
String inverter systems - If your solar panels connect to a single string inverter (the most common setup), you'll usually need to add a "battery inverter" or replace the existing unit with a modern hybrid inverter. In many cases, removing an older PV inverter and upgrading is easier than trying to AC-couple a battery.
Micro-inverter systems - If you have micro-inverters on each panel, you'll need an AC-coupled battery system. These work by converting the AC power from your panels back to DC to charge the battery, then back to AC when you use it.
Power optimiser systems - Similar to string systems, these can usually accommodate a battery with the right additional equipment.
Older systems - Even if your solar is several years old, it can often still support a battery. However, DC-coupling is generally more popular and easier to navigate with flexible or dynamic export limits, as well as site inverter capacity rules. This often makes hybrid solutions a cleaner pathway than adding extra layers of AC-coupled equipment.
The key step is to ask your installer whether your existing inverter can directly support batteries and whether it's smarter to remove and replace old inverters with a hybrid system. A qualified installer can assess your site and guide you to the most efficient and compliant option.
A larger inverter is more useful for Amber customers because it allows you to buy in energy when the price is low, free or negative faster and export energy faster when the price is high which in turn maximises your returns.
Types of battery systems for solar retrofits
When adding a battery to your existing solar system, you'll generally be choosing between two main approaches:
AC-coupled battery systems - These connect to your home's AC electrical system and work alongside your existing solar inverter. They're often the simplest option for retrofits because they don't require major changes to your current setup.
DC-coupled battery systems - These connect directly to the DC side of your solar system, usually by replacing your existing inverter with a hybrid inverter that can manage both solar panels and battery storage. This can be more efficient but often involves more significant changes to your current system.
Your installer will recommend the best approach based on your existing setup, energy usage patterns, and budget.
What to consider before adding a solar battery
Before you jump into a solar battery installation, here are the key factors to think through:
Your energy usage patterns - Do you use most of your electricity in the evening? Are you often home during the day? Understanding when you use power helps determine what size battery makes sense.
Your current solar generation - How much excess solar do you typically export to the grid? This gives you an idea of how much energy you could potentially store instead.
Available space - Batteries need adequate ventilation and protection from extreme temperatures. Most are installed in garages, carports, or suitable outdoor locations.
Your existing inverter - Depending on the age and type of your current solar inverter, you might need to upgrade or add additional equipment.
Budget and payback - Battery prices have come down significantly, but they're still a substantial investment. Consider the long-term savings potential alongside the upfront cost.
Future plans - Thinking of getting an electric vehicle? Planning to add more solar panels? These considerations might influence your battery choice.
The solar battery installation process
Adding a battery to your existing solar system typically involves these steps:
System assessment - A qualified installer will evaluate your current solar setup, electrical panel, and home to determine the best battery solution.
Design and permits - They'll design the system integration and handle any necessary permits or approvals with your electricity distributor.
Installation day - Depending on the complexity, installation usually takes 4-8 hours. This might involve adding new inverters, updating electrical connections, and installing the battery unit itself.
System commissioning - Your installer will test everything, ensure it's working correctly, and show you how to monitor and operate your new battery system.
Grid connection approval - Your electricity distributor needs to approve the updated system before you can start using it (this usually happens automatically within a few days).
Getting the most from your battery investment
Installing a battery is just the beginning. To really maximise your investment, you need to use it smartly. This means charging it when electricity is cheap (or when your solar is generating excess) and using stored power when grid electricity is expensive.
That's where Amber's SmartShift automation comes in. Instead of trying to manually manage when your battery charges and discharges, SmartShift does it automatically based on real-time wholesale electricity prices and your usage patterns.
This means your battery charges when power is cheapest and greenest, and supplies your home when grid electricity is most expensive. It's like having a smart energy manager working 24/7 to optimise your system.
Plus, with Amber's app, you can see exactly what your battery is doing and how much you're saving in real time - not just broad peak and off-peak windows.
Choosing the right installer
Because adding a battery involves both solar and electrical work, you need an installer who's qualified in both areas. Look for:
Solar Accreditation Australia (SAA) accreditation - This ensures they're qualified to work on solar and battery systems safely and to Australian standards.
Experience with retrofits - Adding batteries to existing systems can be more complex than new installations. Choose someone with specific retrofit experience.
Quality brands - Stick with reputable battery brands that are approved for use in Australia and come with solid warranties.
Ongoing support - Your installer should provide ongoing support and be able to help if you have issues down the track.
At Amber, we work exclusively with Clean Energy Council-accredited installers who specialise in quality battery retrofits. They understand how to integrate batteries with existing solar systems safely and effectively.
Is adding a battery worth it?
Whether a solar battery retrofit makes sense depends on your specific situation, but the conditions are increasingly favourable:
Battery prices are falling - Costs have dropped significantly in recent years and continue to improve.
Electricity prices are rising - The more expensive grid electricity becomes, the more valuable stored solar energy is.
Technology is improving - Modern batteries last longer, work more efficiently, and integrate better with smart energy management systems.
Government incentives - Various state and territory rebates can help offset installation costs.
The key is working with the right installer and energy provider to ensure your battery system is properly designed, installed, and managed for maximum benefit.
Ready to explore battery options?
Adding a battery to your existing solar system can be a smart way to get more value from your solar investment and reduce your reliance on the grid. With the right system design and smart automation, you can maximise both your savings and your contribution to Australia's renewable energy future.
At Amber, we're here to help make your battery work harder and smarter. We'll connect you with trusted, accredited installers who specialise in solar battery retrofits, and our SmartShift automation will ensure your battery operates optimally every day.
Want to find out if a battery makes sense for your home? Get in touch with us and we'll help you explore your options with a qualified installer.
