What the inverter is for
The inverter is the system’s traffic controller. It converts DC from the modules to AC, talks to the meter and (sometimes) a battery, and enforces network settings such as export limits and grid-protection trip points.
If the inverter is wrong for the roof, the rest of the hardware cannot save the design. A complicated hip-and-valley roof in inner Brisbane with mixed orientations is not the same job as a simple north plane on a new metal house in Canberra.
String inverter
A string inverter sits on a wall or in a garage and converts a series of modules at one point. It is the workhorse for simple, largely unshaded roofs. Multiple Maximum Power Point Trackers (MPPTs) let a designer put east and west strings on separate inputs — useful on the typical Australian hip roof.
Failures are centralised: one box is easier to service, and one box takes the array offline. Shade on one module in a string can drag the string. That is physics, not a brand scandal.
Place the box out of western-afternoon sun where the site allows it. Garages and southern walls are common. Follow the manufacturer’s clearances; this is licensed work.
Hybrid inverter
A hybrid inverter can manage PV and a battery on one platform. That is useful if storage is in the plan. Two cautions:
- “Hybrid-ready” on a quote often means “you can add a battery later if you buy the matching brand and a rework.” It is not a battery.
- Retrofitting a battery onto a plain string inverter can mean a second box (AC-coupled) or a replacement hybrid. Price that path before you assume “later is cheap.”
Read when a battery makes sense and the batteries guide.
Microinverters (and DC optimisers)
Microinverters convert at each module. DC power optimisers keep a central inverter but add module-level electronics. Both help on complex roofs, mixed orientations, and partial shade — the dormer, the vent, the neighbour’s liquidambar.
They also add more electronic parts on a hot Australian roof. Service access and product warranty length belong on the comparison table. Module-level monitoring can make a fault easier to find; it does not make the roof safe to walk.
Export limits
A DNSP may cap export. The inverter is commissioned to that cap. If a quote assumes unlimited export in a suburb known for constraints — parts of South Australia and increasingly many urban feeders — ask for the connection application in writing. See export limits and how solar works.
CEC listing and firmware
Use a CEC-approved inverter model. Firmware and grid codes change; a listed, supported product matters more than a close-out SKU with no Australian service path. AS/NZS 4777 is the inverter connection conversation your electrician already knows. We will not paraphrase the standard as a DIY checklist.
String vs micro vs hybrid — the honest summary
There is no universal winner.
| Situation | Architecture that usually fits | What to watch |
|---|---|---|
| Simple unshaded roof, no battery | String with enough MPPTs | Shade and future storage path |
| Battery in the plan | Hybrid, or priced AC-coupled path | “Ready” ≠ installed |
| Mixed orientations, stubborn shade | Microinverters or DC optimisers | More roof electronics, warranty length |
| Known export limit | Any of the above, commissioned correctly | The cap, not the brand slogan |
See the essay. Then put the exact model on the quote comparison.
Commissioning is part of the product
An inverter that is never set to the DNSP’s export rule is not “the same box.” Commissioning, grid codes, and firmware support are why a close-out SKU with no Australian service path is a risk. Ask who will return if a firmware change is required after a network rule update.
Place the box where it can be serviced. Western-afternoon sun on a rendered wall in Adelaide cooks electronics. Garages, southern walls, and manufacturer clearances exist for a reason. This is licensed work. We do not publish a DIY mounting height.
Hybrid-ready, AC-coupled, and “later”
Households who might want a battery in two years should still demand a priced path: matching hybrid, AC-coupled second box, or a documented replacement. “Later is cheap” is not a path. See batteries and when a battery makes sense.
If you already have an older string inverter, a retrofit is a design, not an accessory. Compatibility, warranty on the existing box, and switchboard space belong on the quote.
How to brief the designer
Name the roof (tin, tile, mixed, shaded). Name the battery plan (none, maybe, now). Name the export conversation you have already had with neighbours or the DNSP. Then let architecture follow. The string versus micro versus hybrid essay is the short version of this page.
Related money: cost, compare two quotes. Related heritage: mounting hub.
Service path and the ten-year box
Inverter warranties are commonly shorter than module performance warranties. Budget a replacement in the life of the array. That is planning, not a scare. Ask who services the box in Australia and whether firmware is still supported. A close-out SKU with no path is how a “cheap upgrade” becomes a stranded array.
Place the box out of western-afternoon sun where the site allows it. Follow clearances. This is licensed work.
If export is constrained, the architecture still matters for shade and batteries, but the cap sits above the brand. See export limits. If a battery is a maybe, price the path now. See when a battery makes sense.
MPPT, strings, and the hip roof
Most Australian houses are hips and valleys, not a single north barn. Multiple MPPTs exist so an east string and a west string do not drag each other. That is a string-inverter strength when the roof is otherwise simple. It is not a reason to ignore a chimney shadow that sits on one module all winter.
Microinverters and optimisers earn their keep when the shade map is stubborn or the orientations are mixed beyond what MPPTs can separate. They cost more electronics on a hot roof. Say that trade-off out loud. Then name the model. See how solar works and compare two quotes.
General information only. Confirm listings and grid settings with the installer and the DNSP. Last reviewed 25 September 2026.