When planning a solar plus battery system in Australia, one of the most confusing decisions is choosing between a hybrid inverter and a standard string inverter paired with a separate battery inverter. The difference isn't just technical — it has real implications for cost, flexibility, and future-proofing your system. Here's a clear guide to help you choose the right setup for your home.
What Is a Hybrid Inverter?
A hybrid inverter is a single unit that handles three jobs simultaneously: converting solar DC power to AC for home use, managing battery charging and discharging, and controlling the flow of power between solar panels, battery, home, and grid. It replaces what would otherwise require a separate solar inverter and a separate battery inverter.
Popular hybrid inverters in Australia include the Sungrow SH series, Fronius Symo GEN24, Goodwe ET series, and Huawei SUN2000. They're paired with compatible battery packs — either proprietary (like the Sungrow SBR battery) or third-party (like BYD Battery-Box or Alpha ESS).
What Is a String Inverter + Battery Inverter Setup?
A standard string inverter (like a SolarEdge, Fronius Primo, or SMA Sunny Boy) converts solar generation to AC power. To add battery storage later, you install a separate battery inverter (or AC-coupled battery like a Tesla Powerwall) that connects to your AC switchboard. Each device manages its own job.
This is the most common setup in Australian homes that installed solar before 2020, and then decided to add a battery later. It's also why the Powerwall became so popular — it's an AC-coupled solution that works with any existing solar system. Our dedicated comparison of AC-coupled versus DC-coupled batteries unpacks the efficiency and retrofit trade-offs in more detail.
Hybrid vs String Inverter: Head-to-Head Comparison
| Feature | Hybrid Inverter | String Inverter + Battery Inverter |
|---|---|---|
| Upfront cost | Lower (one device) | Higher (two devices) |
| Installation complexity | Simpler | More complex |
| Efficiency (DC coupling) | Higher (~97%) | Slightly lower (AC coupling ~95%) |
| Battery brand flexibility | Limited to compatible brands | Greater flexibility (AC coupling) |
| Adding solar + battery together | Ideal | Fine, but redundant hardware |
| Retrofitting to existing solar | Requires replacing inverter | No change to existing inverter |
| Backup power capability | Built-in (model dependent) | Depends on battery inverter |
| Monitoring | Unified app | May need separate monitoring platforms |
Cost Comparison: What You'll Actually Pay
Here's a realistic installed cost comparison for a 6.6kW solar system with a 10kWh battery in Australia in 2026:
| Configuration | Installed Cost (approx.) |
|---|---|
| 6.6kW solar + hybrid inverter only (battery ready) | $6,500–$8,500 |
| Add-on compatible battery (10kWh) to hybrid | $7,000–$10,000 |
| Total: hybrid solar + battery | $13,500–$18,500 |
| 6.6kW solar + standard string inverter | $5,500–$7,500 |
| AC-coupled battery (Tesla Powerwall 3, 13.5kWh) | $12,000–$15,000 |
| Total: string inverter + AC battery | $17,500–$22,500 |
The hybrid setup is typically $2,000–$5,000 cheaper for a simultaneous solar + battery installation. However, the string + AC battery approach gives you more battery brand options and doesn't lock you into a single ecosystem.
When to Choose a Hybrid Inverter
A hybrid inverter is the better choice when:
- You're installing solar and battery together from scratch
- You want a simpler system with unified monitoring in one app
- You want DC-coupled efficiency (especially important for smaller batteries)
- You don't need maximum flexibility in battery brand choice
- You're installing in a new build or undertaking a complete system replacement
When to Choose a String Inverter + Separate Battery
The string inverter approach makes more sense when:
- You already have a working string inverter and want to add battery storage without replacing it
- You want the maximum flexibility to choose any battery brand (including Tesla Powerwall)
- You have a 3-phase supply and need a 3-phase capable battery inverter
- Your existing inverter is under warranty and replacing it wastes that value
Future-Proofing: Which System Scales Better?
Both systems can be expanded, but in different ways. Hybrid inverters generally support adding more battery capacity up to the inverter's rated limit (often 20–30kWh). String inverter + AC battery setups can add additional battery units as long as the battery brand supports expansion packs.
If you're planning to add an EV and want to use vehicle-to-home (V2H) in the future, check that your chosen hybrid inverter supports V2H — not all currently do. This is an emerging consideration for 2026 and beyond.
Build Your System With Confidence
The best inverter choice depends on your specific situation — whether you're starting fresh or retrofitting, your phase supply, your preferred battery brand, and your budget. Use our Solar + Battery System Builder to compare complete system configurations including inverter type, panel output, and battery sizing. It runs the numbers on your usage data so you can see exactly what each configuration returns over 10 years.