Not every solar job starts from scratch. This project involved a Grantham homeowner who already had panels on their roof but wanted to get more out of them, along with a way to store power for use after dark.
Rethink Green Energy expanded the existing system with 11 additional panels and added a 20kWh GoodWe battery, giving the property extra generation and genuine backup storage. The result was a system tested, compliant, and ready for grid connection in a single day.
The homeowner already had a solar system on their property in Grantham, but like a lot of established solar owners, they were only getting half the benefit. Most of the power their panels made during the day went straight back to the grid for a small feed-in credit, and every evening they were buying electricity back at full retail price.
With power prices continuing to climb across Queensland and battery rebates making storage more affordable, the homeowner wanted a way to actually use more of the power their roof was already producing. Adding a few extra panels made sense too, since the existing array wasn't covering everything the household needed on shorter winter days.
The brief was straightforward: boost generation, add proper storage, and do it without disrupting the system that was already working well.
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Our team assessed the existing setup and designed an expansion rather than a replacement. Eleven additional 475W Jinko Solar panels were added to a north-facing section of the roof, the best orientation available on the property, lifting total generation by 5.225kW.
For storage, we specified a GoodWe GW5.1-BAT-D-G20 battery system made up of four modules, giving the home 20.48kWh of nominal capacity and 20kWh usable. It was paired with a GoodWe GW9.999K-EHA-G20 hybrid inverter, which is virtual power plant capable, so the homeowner has the option to join a VPP program down the track if they choose to.
Every product on this job comes from brands already on our approved supplier list, chosen for proven reliability across Queensland and New South Wales conditions rather than the lowest price on paper.
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Our licensed installation team completed the work on site on 30 April 2026. The additional panels were mounted and wired into the existing array, the battery and inverter were installed and connected to the switchboard, and the whole system was tested end to end before being signed off.
The job included full compliance documentation: an STC assignment form confirming the system's eligibility for 204 Small-scale Technology Certificates, a Queensland Certificate of Testing and Compliance covering both the electrical installation and equipment, and a retailer written statement confirming the battery was correctly sized, grid connected, and ready for VPP participation.
By the end of the day, the system was generating, storing, and exporting exactly as designed, with every serial number, test result, and compliance document filed and ready for the homeowner's records.
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This job is a good example of the upgrade work a lot of existing solar owners are now looking for. Rather than starting from scratch, the homeowner added 5.225kW of extra generation and 20kWh of usable storage to a system that was already in place, which is often the more cost effective path once battery rebates are factored in.
It also shows how far storage has come. Instead of exporting daytime solar for a few cents a kilowatt hour and buying it back at night, the homeowner can now store that power and use it after the sun goes down, with the added flexibility of VPP participation if the right program comes along.
We are a family owned, Australian operated business, and every install is completed by CEC accredited installers backed by a 25 year workmanship warranty. Jobs like this one are why we build systems the way we do: sized honestly for what a property actually needs, not oversold to make the sale bigger.
Our support does not stop once the panels are on the roof. We offer ongoing system monitoring, maintenance, cleaning, and repairs, so customers who added solar with us years ago can keep upgrading with a team that already knows their system.
If your solar system is already working hard but you're still paying peak rates every night, it might be time to add storage. Book a free, no obligation assessment with Rethink Green Energy and we'll show you exactly what a battery, or a few extra panels, could do for your home.
We're your local green energy partners, deeply devoted to brightening our community with sustainable power solutions.
