Microinverter
A small inverter mounted on each individual solar panel that converts DC to AC at the panel level — eliminating shading losses and enabling panel-level monitoring.
Microinverters (pioneered by Enphase Energy) perform DC-to-AC conversion at each individual panel rather than centrally. Because each panel operates independently, shading or underperformance of one panel has zero effect on the others — the system produces maximum possible power regardless of partial shading or panel mismatch.
Additional advantages: panel-level monitoring identifies exactly which panel is underperforming; AC wiring is simpler and potentially safer; there is no single point of failure (if one microinverter fails, only one panel is affected, not the entire system); and microinverters typically carry 25-year warranties matching the panels themselves, eliminating the string inverter replacement cost in year 12–15.
Disadvantages: microinverters cost $100–$200 per panel more than string inverters; they are exposed to heat (mounted behind panels) which can affect long-term reliability in extreme climates; and roof access is required for maintenance versus a ground-level central inverter. For unshaded simple roofs, the production benefit rarely justifies the premium; for shaded or complex roofs, the benefit often does.
Real-World Example
Enphase's monitoring app showed that panel 7 (facing southeast) produced 18% less than the adjacent panels; after inspection, the installer found a loose connection that would have gone undetected for months with a string inverter.