Hybrid inverters in Perth: what they are and when you need one

When you buy solar panels, you also buy an inverter. When you add a battery, you need a way to connect the battery to the system. How that connection works — and whether you need a different type of inverter — is the core question that separates hybrid systems from standard string systems.

The difference between a string inverter and a hybrid inverter

String inverter (conventional): Converts DC electricity from the solar panels into AC electricity for use in the home and grid. That's all it does. It has no battery connection capability.

If you want to add a battery to a string inverter system, you need an additional AC-coupled battery inverter/charger (like a Powerwall 2 or Alpha-ESS in AC-coupled mode). This works, but involves two separate power conversion steps: panels → string inverter (DC to AC) → battery inverter (AC back to DC to charge battery, then DC to AC again on discharge). Each conversion step loses approximately 3–5% efficiency.

Hybrid inverter: Combines the solar inverter and battery inverter into a single unit. The battery connects to the DC side of the hybrid inverter, so solar energy can charge the battery directly without an extra conversion step. More efficient, simpler wiring, typically lower total installed cost when battery is included.

DC coupling vs AC coupling

These terms describe how the battery connects to the rest of the system:

DC coupling (hybrid inverter): Solar panels → DC bus inside the hybrid inverter → battery charges from DC bus OR DC bus converts to AC for home use. One conversion step. Efficiency advantage: approximately 3–7% better round-trip efficiency than AC coupling.

AC coupling (standard string + AC-coupled battery): Solar panels → string inverter → AC bus → AC-coupled battery inverter → battery. Two conversion steps. Slightly less efficient but works with any existing solar system.

| | DC coupling (hybrid) | AC coupling (separate) | |---|---|---| | Inverter type | One hybrid unit | Two separate units | | Battery connection | DC side | AC side | | Efficiency | Higher (~95% RT) | Slightly lower (~90% RT) | | Suitable for retrofit | Requires new inverter | Works with existing system | | Cost (solar + battery together) | Typically lower | Typically higher |

When to choose a hybrid inverter

Installing solar and battery at the same time: A hybrid inverter is almost always the right choice. One unit, DC coupling efficiency, simplified installation.

Planning to add a battery within 2–3 years: Buy a hybrid inverter from the start. The marginal cost of upgrading to hybrid when installing solar is much less than replacing a string inverter later.

Large system (8kW+) with battery: Hybrid inverters at higher capacities (8kW, 10kW) are well-supported by major brands.

When to choose a string inverter (or AC-coupled battery)

Solar only, no battery planned: A quality string inverter is simpler and sometimes less expensive. If there's genuinely no battery in your plans, the hybrid's battery features add cost for no immediate benefit.

Retrofit battery to an existing string system: If your string inverter is functioning and relatively recent (under 7 years old), AC coupling the battery makes sense — replace a working inverter only when it fails, not before.

Three-phase systems with specific requirements: Some three-phase configurations are better served by separate string + battery inverters.

Popular hybrid inverters in Perth (2026)

Fronius GEN24 Plus (5kW, 8kW, 10kW): Compatible with BYD Battery-Box (standard) and Fronius BYD-based storage. Strong monitoring via Solar.web. Good Australian support.

SolarEdge Home Hub (5kW, 10kW): Works with SolarEdge Home Battery. Power optimiser architecture carries through.

Sungrow SH series (5kW, 8kW, 10kW, 15kW): Pairs natively with Sungrow SBR battery. Competitive pricing. iSolarCloud monitoring.

Goodwe DNS/ES/ET series: Good value option. Supports multiple battery brands via CAN bus. Less Australian service depth than Fronius/Sungrow.

Growatt SPH series: Budget hybrid option. Budget pricing comes with lower Australian support depth.

Battery compatibility

Not all hybrid inverters work with all batteries. Most use proprietary or semi-proprietary communication protocols:

• Fronius GEN24 → BYD Battery-Box (native) + some others
• SolarEdge Home Hub → SolarEdge Home Battery
• Sungrow SH → Sungrow SBR (native) or BYD via third-party wiring
• Goodwe → BYD, Pylon, and others via CAN bus

Confirm battery compatibility with your installer before specifying a system. Don't assume a hybrid inverter from one brand works with a battery from a different brand without verifying.

Hybrid inverter pricing and battery compatibility current as of June 2026. Specifications change with firmware updates and new product releases.