Inverters & components
Solar panel optimisers explained
Power optimisers are a third way to handle panel-level performance, sitting between the simplicity of a string inverter and the independence of microinverters. They come up often in rooftop solar, less so in plug-in systems.This guide explains what they do and where they fit. For the bigger picture, see the inverter hub.
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.
What an optimiser does
A power optimiser attaches to each panel and tracks that panel's optimum operating point, then passes conditioned DC down to a central string inverter. The result is better panel-level performance — especially with shade or mismatched panels — while still using one central inverter for the actual DC-to-AC conversion.
Optimisers versus microinverters
Both work at panel level, but a microinverter converts to AC at the panel, whereas an optimiser conditions DC and leaves conversion to a separate string inverter. We compare the two directly in optimisers vs microinverters.
Are optimisers relevant to plug-in solar?
Mostly not. Plug-in systems are small and built around a microinverter that produces mains-compatible AC at the panel — there's no central string inverter for an optimiser to feed. Optimisers are far more relevant to larger rooftop installations. Knowing the difference still helps when comparing systems.
Frequently asked questions
- What is the difference between an optimiser and a microinverter?
- Both work per panel. An optimiser conditions the panel's DC and sends it to a central string inverter for conversion; a microinverter converts to AC at the panel itself. Plug-in solar uses microinverters.
- Do plug-in solar systems use optimisers?
- Generally no. They use microinverters that output AC directly, so there's no central inverter for an optimiser to work with. Optimisers are mainly used on larger rooftop systems.
Sources
- 1. Engineering Recommendation G98 (connecting small generation) — Energy Networks Association
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