Your Local Electrical & Solar Specialists in Tweed Heads

As a rough guide, a complete quality solar and battery system will generally cost around $15,000–$20,000 for a 6.6kW solar system with a 10–15kWh battery, $20,000–$26,000 for a 13kW solar system with a 20–25kWh battery, and $30,000–$45,000 for a larger 20–30kW solar system with around 30kWh of battery storage.

Installing solar and a battery together can also be more cost-effective than installing them separately, as they can share a hybrid inverter and much of the installation work is completed at the same time. The final price depends on the solar size, battery capacity, equipment, backup requirements, switchboard and complexity of the installation.

As a rough guide, a quality battery system will generally cost around $9,000–$16,000 for a 10–15kWh battery, $14,000–$20,000 for a 20–25kWh battery, and $15,000–$25,000 for a 30kWh battery.
These prices include installation and assume the applicable federal battery rebate. The final cost depends on the battery brand, your existing solar and inverter setup, backup requirements, switchboard work and the complexity of the installation.

It depends entirely on who’s asking and what you’re trying to achieve. For some people it’s purely a financial decision and they want the shortest possible payback period. Others experience regular blackouts, want greater energy independence, don’t like paying electricity retailers for power they could produce and store themselves, or simply value having the technology and greater control over their own energy.
If your goal is purely financial, then the numbers need to stack up. Battery payback depends on how much electricity you use, when you use it, how much excess solar you have available, your electricity tariff, battery size and the installed cost. As a rough guide, many well-designed residential battery systems can have simple payback periods somewhere around 7–10 years, although higher-energy users and systems with high utilisation can achieve significantly shorter payback periods.
There’s also a longer-term way to look at it. If a properly sized solar and battery system can supply around 90–95% of your electricity needs over the year, you’re dramatically reducing the amount of electricity you need to buy from the grid. That means much less exposure to future electricity price increases and much greater control over what your household pays for energy over the long term.
That doesn’t necessarily mean going completely off-grid. For most homes, staying grid-connected makes much more sense. Going off-grid generally requires significantly more solar, battery capacity and often backup generation to reliably get through extended periods of poor weather. Staying connected gives you the grid as a backup while allowing your solar and battery to provide the vast majority of your energy.
How long you plan to stay in the property matters too. If you’re planning to sell in a few years, you’ll look at the investment very differently from someone expecting to live there for another 10–20 years. And financial return isn’t the only value — blackout protection, reduced reliance on the grid and having stored energy available when you need it can be worth different amounts to different people.
That’s why we don’t think there’s an honest yes-or-no answer to “Is a battery worth it?” The better question is: what are you trying to achieve? Once we know that, we can look at your actual energy usage and work out whether a battery makes sense for you.

We start with your average daily electricity consumption and then account for any future loads you’re likely to add, such as a battery, EV, pool, air conditioning or electric hot water. We then assess your available roof space, orientation and shading to work out how much solar the property can realistically produce.
Where suitable roof space is available, we generally recommend allowing some extra solar capacity rather than designing the system right on the limit of what you use today. In our experience, households often start using more electricity once they have solar, and a larger system also gives you more generation capacity during cloudy and rainy periods when solar production can be significantly reduced. Adding extra panels during the original installation is also generally much more cost-effective than trying to expand the system later.
There isn’t one system size that’s right for everyone. A low-usage household might only need around 6.6kW, while for a typical family home we often find systems closer to 10–13kW make more sense. The goal isn’t simply to fill every roof with panels — it’s to install as much solar as the household can reasonably make use of now and into the future.

The right battery size depends on what you’re trying to achieve. As a general guide, a battery sized at around 60–70% of your average daily electricity consumption can often provide a strong return on investment, because you’re more likely to regularly use and recharge most of the battery’s available capacity.
For most of our installations, however, we like to start closer to 100% of the home’s average daily consumption. So if your home uses around 20kWh per day, we’d generally look at around 20kWh of battery storage. This is slightly oversized from a pure short-term ROI perspective, but we think it’s a good sweet spot — giving you more capacity for poor weather, backup power, future increases in electricity usage and changes to the way you use your home.
If we can access your smart-meter or monitoring data, we can refine this further by looking at when you actually use electricity and how much excess solar is available to recharge the battery. We’ll also consider future loads such as an EV, electric hot water, pool equipment or additional air conditioning.
VPPs are different again. If participating in a Virtual Power Plant is part of your plan, additional battery capacity can be valuable because you want enough stored energy to cover your own household needs while still having capacity available for the VPP. As a rough starting point, we’d consider around 20kWh of battery capacity above the home’s normal daily consumption, then size the system properly around the particular VPP and how it operates.

If you already know you want a battery and the budget allows, installing the solar and battery together will always be more cost-effective than installing the same system in two separate stages. The whole system can be designed together, the solar and battery can share a hybrid inverter, and much of the installation work only needs to be completed once. It will also nearly always result in a neater installation, because adding a battery later can mean redoing finished work — running additional cables, modifying enclosures, drilling new penetrations or changing parts of the original installation.
A battery can be added later, but there are a few things people often aren’t told. Solar and battery technology changes quickly, manufacturers replace older models, and Australian standards, regulations and Clean Energy Council approved-product listings change over time. In some cases, even equipment installed only 12 months earlier may no longer have the same approval status or be the current model when you come back to expand the system. This can affect compatibility, system design and eligibility for government incentives on the new installation.
We’ve seen this ourselves with existing systems. Sometimes adding a battery later is straightforward; other times the existing inverter, panels or other equipment are no longer compatible, don’t meet the current requirements for the proposed upgrade, or make the upgrade unnecessarily expensive. In some cases, it can make more financial sense to replace relatively young equipment than try to integrate new technology with it.
Our general advice is simple: if you know you want solar and a battery and can afford to do both now, do it properly once. If the budget doesn’t allow it, we can absolutely install solar now with a future battery in mind — but nobody can guarantee that today’s equipment, approvals, regulations or compatibility will still be the same when you’re ready to add the battery.

Yes. A battery can be added to essentially any existing solar system. The bigger question is how we integrate it, because the cost, performance and amount of work required can vary significantly depending on the solar system you already have.
With some systems, adding a battery can be relatively straightforward. With others, we may need to replace or add an inverter, modify the switchboard, change the system configuration or AC-couple the new battery to the existing solar system. The age, size, brand and approval status of your existing equipment can all affect the best solution.
We also need to look at whether your existing solar system produces enough excess energy to actually charge the battery. If most of your solar is already being consumed by the property during the day, there may be little benefit in adding a large battery unless we also increase the amount of solar or you’re planning to charge the battery from the grid during cheap or free electricity periods. Electricity plans and tariffs change, so we wouldn’t design a system that only makes financial sense because of a temporary retailer offer.
We also look at whether keeping the existing solar system actually makes financial sense. If you have an older or undersized system, sometimes spending more money trying to integrate a new battery into old equipment isn’t the best option. It may be more cost-effective to upgrade part or all of the solar system at the same time and design everything to work together properly.
So the short answer is yes — we can add a battery to an existing solar system. But before recommending one, we’ll look at what you already have, how much excess solar you produce and what you’re trying to achieve, then work out the most cost-effective way to integrate a battery without unnecessarily replacing equipment that’s still doing its job.

Yes. When we install a battery, we always include backup power. With a smaller system using around a 5kW inverter, we’ll generally back up the kitchen power circuit, which keeps the fridge running and gives you access to the kitchen power points if you need to plug in an extension lead for other essential equipment. Where possible, we’ll also keep the internet router powered. Keeping the internet running means your solar and battery monitoring can stay connected, so you can keep an eye on your battery charge and energy usage throughout the outage. With a 10kW or larger inverter, we generally provide whole-house backup.
When we’ve sized the battery at around the home’s normal daily electricity consumption and provided whole-house backup, you generally don’t need to change the way you live just because the power goes out. You can continue using the house relatively normally, while keeping in mind that the inverter still has a maximum power output and there is a limit to how many high-powered appliances can run at the same time.
Where you need to become more conscious of your electricity use is during an extended, multi-day blackout — particularly if there are several days of poor weather. At that point, we’d recommend reducing unnecessary loads and prioritising essentials such as refrigeration, lighting, internet, general power and other important equipment to make the stored energy last longer.
All of the solar and battery systems we install are designed so the solar can continue producing power during the day while the grid is down. The solar can power the home and recharge the battery, so on a good solar day you may be able to replace much or all of the energy you used overnight without the grid being available.
We discuss your backup requirements before designing the system. If running air conditioning, pumps or other high-powered equipment during a blackout is important to you, we’ll take that into account when sizing and configuring the inverter and battery.

A properly designed solar and battery system can dramatically reduce the amount of electricity you need to buy from the grid. For a system designed to cover most of a household’s energy needs, we can often aim for around 90–95% energy independence over the year — meaning only a relatively small percentage of your electricity needs to come from the grid.
Solar-only systems are different. How much you save depends heavily on when you use electricity. Solar is most valuable when the power is being used directly in the property, while excess energy exported to the grid is generally worth much less than the electricity you buy back later. Adding a battery allows us to store that excess daytime solar and use it at night, substantially increasing how much of your own solar energy you can use.
Even with a large solar and battery system, your electricity bill won’t necessarily disappear completely. You’ll generally still have daily grid connection charges, and there will be periods of poor weather where you need to import some electricity. The goal isn’t necessarily a $0 bill every month — it’s to minimise how much electricity you need to buy from the grid over the long term.
High-energy users can sometimes achieve particularly strong returns from solar because a greater percentage of the energy being generated can be consumed directly onsite rather than exported to the grid. This is particularly relevant for businesses and other properties with high daytime electricity consumption, where a well-sized solar system can have an excellent return on investment.
The actual savings depend on your electricity consumption, when you use power, system size, solar production, battery capacity, electricity tariff and how your usage changes over time. That’s why we design systems around your actual energy use rather than promising every customer the same percentage saving.