How each type works
Solar panels make direct current (DC). Your home and the grid use alternating current (AC). The inverter does the conversion, and it is the part of a system most likely to need replacing.
With a string inverter, panels are wired together in one or more strings, and the whole string runs at the current of its weakest panel. With microinverters, each panel has its own small inverter, so a shaded panel only affects itself, and only AC cabling runs across the roof. With optimisers, each panel is tuned individually, then a central inverter does the conversion.
String inverters, optimisers and microinverters compared
String inverter
Most common- Lowest cost
- One unit to service, mounted where you can reach it
- Hybrid versions can run a battery
- Shade on one panel reduces the whole string
- System-level monitoring only, unless extras are added
- Typical warranty around 10 years
Microinverters
Panel level- Each panel works on its own, good for shade and split roofs
- Panel-by-panel monitoring
- Long warranties, 25 years on Enphase IQ8 in Australia
- Higher upfront cost
- Electronics on the roof, so faults mean a roof visit
- Batteries usually need to be AC coupled
Optimisers sit between the two: panel-level tuning and monitoring with one central inverter. SolarEdge, the main optimiser brand, quotes 12 years on its inverters and 25 years on its optimisers. See our guides to Enphase, SolarEdge, Fronius and Sungrow.
Which one suits your roof
| Your situation | Usually suits |
|---|---|
| One unshaded roof face | String inverter |
| Panels on three or more roof faces | Microinverters or optimisers |
| A tree, chimney or neighbour shades part of the roof | Microinverters or optimisers |
| Battery planned soon | Hybrid string inverter, or microinverters with an AC battery |
| Tight budget | String inverter |
Ask for a shade analysis
A good installer will look at shade across the year, not just on the day of the visit. Winter shadows are much longer. See orientation and shading.
Common questions
Not always. They help on shaded roofs and roofs with panels facing several directions, and they carry long warranties. On a simple unshaded roof a string inverter does the job for less.
Yes, usually with an AC-coupled battery such as the Enphase IQ Battery, or another AC battery with its own inverter.
Warranties are a guide: around 10 years is typical for string inverters, 12 for SolarEdge inverters, and 25 years for Enphase IQ8 microinverters activated in Australia from 1 October 2024.
Sources
General information comes from Australian Government sources. Warranty terms come from each manufacturer's Australian warranty documents. Last checked October 2026. Prices include GST unless we say otherwise.