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MyPlugInSolar

Inverters & components

Optimisers vs microinverters: which is which?

Optimisers and microinverters both improve performance panel by panel, which is why they're often confused. The difference comes down to where the DC-to-AC conversion happens.This guide lays the two side by side. For each on its own, see optimisers and microinverters.

Written and edited by Christopher Panteli

Christopher is the founder and editor of MyPlugInSolar. He oversees the site’s research standards, data tools and editorial process. He is not an electrician or solar installer, and specialist technical claims are sourced from official documentation or reviewed by appropriately qualified professionals.

The core difference

A microinverter is a complete inverter per panel: DC goes in, mains-compatible AC comes out, with grid protection built in. An optimiser is not an inverter — it conditions the panel's DC and relies on a separate central string inverter to do the conversion. So a microinverter system needs no central inverter, while an optimiser system does.

Optimisers vs microinverters at a glance.
AspectMicroinverterOptimiser
Output at panelACConditioned DC
Central inverter needed?NoYes (string inverter)
Grid protectionBuilt into each unitHandled by the string inverter
Typical usePlug-in & panel-level rooftopLarger rooftop systems

Why it matters for plug-in solar

Plug-in systems are small and need AC at the panel so the output can connect through a lead. That's exactly what a microinverter provides, which is why plug-in solar uses them and not optimisers. For the components a plug-in system actually uses, see the inverter hub.

Frequently asked questions

Which is better, an optimiser or a microinverter?
Neither is universally better — they suit different systems. Microinverters output AC at the panel and suit small plug-in systems; optimisers condition DC for a central inverter and suit larger rooftop installs.

Sources

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