Microinverter
A microinverter is a small solar inverter installed on each individual solar panel, converting that panel's DC output to AC electricity at the module level. Unlike string inverters that handle multiple panels together, each microinverter operates independently, enabling panel-level maximum power point tracking and monitoring.
Enphase Energy is the market leader in microinverters, with their IQ series used in millions of residential installations worldwide.
Advantages of Microinverters
Shade tolerance: Since each panel operates independently, shading, soiling, or failure of one panel does not degrade the others. This makes microinverters ideal for complex rooftops with multiple orientations or intermittent shading.
Panel-level monitoring: Each panel's production is monitored individually, allowing precise identification of underperforming panels.
Safety: Microinverters produce AC power at the module, eliminating high-voltage DC wiring runs from the roof to the inverter. This is a significant safety advantage in rapid shutdown scenarios (important for fire safety codes).
Expandability: Adding panels to a microinverter system is straightforward — each new panel gets its own microinverter.
Disadvantages of Microinverters
Higher cost: Microinverters cost more per watt than string inverters, typically adding $0.10–0.20/W to system cost.
Reliability concerns: More inverter units mean more potential failure points, though modern microinverters have strong 25-year warranties.
Efficiency: Microinverters are slightly less efficient than string inverters at the unit level.
When to Choose Microinverters
Microinverters are preferred for:
- Shaded rooftops (trees, chimneys, neighboring buildings)
- Roofs with multiple pitch orientations
- Homeowners who want panel-level monitoring
- States with rapid shutdown requirements