What is the difference between a string inverter and microinverters?

A string inverter is one central box that converts power for all your panels wired together in series, so shade or a fault on one panel can drag down the whole string. Microinverters convert power at each individual panel, so panels work independently and one problem does not affect the rest.

Are microinverters worth the extra cost?

On a simple, unshaded, north-facing roof, usually not: a quality string inverter performs well for less money. On roofs facing multiple directions, with shading, or where you want per-panel monitoring, microinverters or optimisers often earn back their premium of roughly $1,000 to $2,500 through better output and easier fault-finding.

What is a hybrid inverter?

A hybrid inverter is a string inverter that can also charge and discharge a battery. If you plan to add a battery within a few years, quoting a hybrid inverter now can save replacing the inverter later, but check which battery brands and sizes it supports.

String, microinverter or optimiser: the one question about your inverter that changes everything

Every solar quote names an inverter, and most people skim straight past it to the price. That is a mistake. The inverter setup decides what happens when something goes wrong on your roof, how well the system handles your roof's shape, and what you can add later. Here is the plain-English version.

The three setups

String inverter. One box on the wall. Your panels are wired together in a series, called a string, and all their power flows through that one box. This is the most common and cheapest setup, and brands like Fronius, Sungrow and GoodWe make excellent ones.

Microinverters. No central box. Each panel gets its own small inverter on the back, so every panel operates independently. Enphase is the brand you will see on Australian quotes.

Optimisers. A middle path. A small optimiser sits on each panel managing it individually, but the actual conversion still happens in one central inverter. SolarEdge is the main name here.

The failure question

Here is the question that separates the setups: what happens when one panel fails, gets shaded, or a fault develops?

On a string system, panels in a string behave like a team roped together. A badly shaded or faulty panel can pull down the output of the whole string, and if the central inverter itself fails, the entire system stops until it is replaced.

On a microinverter or optimiser system, each panel is managed on its own. One shaded or failed panel costs you that panel's output, and nothing else. Per-panel monitoring also means a fault shows up in an app pointing at the exact panel, rather than as a mysterious drop in total output you notice months later on a bill.

That resilience is real, but keep it in proportion: a central inverter failing is disruptive, yet quality string inverters carry 10 year warranties and are a single, straightforward component to swap. Microinverters put more electronics on the roof, where heat lives, and replacing one means getting up there.

Which roof needs which

Simple north-facing roof, no shade: a quality string inverter is usually the sensible buy. The premium for panel-level electronics buys you little extra output here.
Roof facing two or more directions: string inverters handle this with a maximum of two separate strings, one per orientation. Three orientations, or complicated roof planes, push you toward optimisers or microinverters.
Shade from trees, chimneys, antennas or neighbouring buildings: panel-level electronics earn their keep. This is the clearest case for them.
Planning a battery: ask about a hybrid inverter now. It converts power for the panels and manages a battery in one unit, which can save you replacing a standard inverter when the battery arrives. Check which batteries it supports before assuming.

What it does to the price

Expect microinverters or optimisers to add roughly $1,000 to $2,500 to a typical home system compared with a good string inverter. That is not a rip-off, it is more hardware. The question is whether your roof actually needs it. A premium quote on a simple roof deserves the question "why not a string inverter?", and a cheap string quote on a heavily shaded roof deserves "how will this handle the shade?"

The pitfalls to watch

A quote that does not name the inverter setup at all. Ask. If the answer is vague, that tells you something about the installer.
Panel-level electronics sold as essential on a simple unshaded roof. They are an upgrade, not a requirement.
A hybrid inverter quoted without naming which batteries it supports, which can quietly lock you into one brand later.
Any inverter not on the Clean Energy Council's approved list, because rebates depend on approved components.

Check what you were quoted

Our free Quote Checker reads your quote, tells you which setup you were quoted, how the price sits against the published Melbourne range for your system size, and gives you the questions to take back to the installer. It takes under a minute and stores nothing that identifies you.