Case Study Millmerran Woods Off Grid Solar System
A recent installation at Millmerran Woods in regional Queensland shows what a well balanced medium sized off grid solar system looks like in practice.
System overview
- 6.6 kW Suntech solar array
- 5 kW Victron MultiPlus inverter charger
- 20 kWh battery bank using 4 × Pylontech US5000 batteries
The system was designed for a rural residential property with typical daily loads, where the priority was dependable, low maintenance operation.
Why this off grid system works
The strength of this system comes from how the solar array, battery storage and inverter have been sized to work together rather than simply choosing the largest components available.
Solar array sized for Queensland conditions
The 6.6 kW Suntech solar array provides strong daily production while remaining practical for available roof space and overall system sizing.
It was not designed only around ideal sunny days. The system needs enough generation to help recover the battery bank after cloudy periods, support winter energy requirements and reduce generator reliance throughout the year.
This system sits between our standard 5 kW off grid solar system and a larger 15 kW off grid solar system, making it suitable for moderate rural energy use.
Battery storage matched to usage
The 20 kWh Pylontech battery bank provides overnight capacity and additional energy storage for periods of lower solar production.
The system was balanced so the solar array can regularly recharge the battery bank rather than installing more storage than the available solar generation can realistically support.
The modular design of the Pylontech US5000 also makes future battery expansion more straightforward if the property’s energy requirements change.
A proven inverter platform
The 5 kW Victron MultiPlus is used to manage household loads and integrate battery storage within the off grid system.
The inverter was selected to suit the property’s expected electrical demand rather than simply specifying a larger unit without considering the wider system.
You can read more about why we use Victron inverters across our off grid projects.
Designed as a complete system
The individual components are important, but how they work together matters more. This installation was designed around the property’s actual load profile, available solar generation, battery capacity and backup requirements.
That whole system approach is something we apply to every Queensland off grid system we design.
Why balance matters in off grid design
Bigger components do not automatically create a better off grid system.
If the battery bank is too large for the solar array, it may struggle to recover after extended poor weather. If the inverter is undersized, normal household loads can exceed its capacity.
The Millmerran Woods system was designed around how the property is actually used, keeping solar generation, storage and inverter capacity in balance.
Generator backup done properly
Like many off grid systems, this setup includes generator backup. Because the solar, battery and inverter components are sized around the property’s requirements, the generator is there to support the system when required rather than act as the primary energy source.
Is a system like this right for your property?
A similar configuration may suit your property if:
- You’re powering a standard rural home with moderate, consistent energy use
- You want reliable power without overspending on unnecessary capacity
- You’re looking for a long term setup rather than a temporary solution
If your energy needs are smaller, a 3 kW off grid solar system or a small cabin off grid power system may be a better starting point.
Other completed off grid projects
Talk to us about your off grid system
Every property is different, and getting the design right from the start is what makes the difference between a system that performs reliably and one that becomes frustrating later.
If you’re considering an off grid system or upgrading an existing setup, we can help design something tailored to your property and how you actually use power.