What's the Difference?
Microinverters
Small inverters attached to each individual solar panel. Each panel operates independently, converting DC to AC at the panel level. Plug-and-play kits use UL 1741-certified microinverters — see our UL 1741 guide and best microinverters for balcony solar.
String Inverters
Single central inverter that converts DC from multiple panels (connected in series) to AC. All panels feed into one inverter.
Detailed Comparison
| Feature | Microinverter | String Inverter |
|---|---|---|
| Cost per Watt | $0.25-$0.40/W | $0.10-$0.20/W |
| Shading Performance | Excellent | Poor |
| Panel-Level Monitoring | Yes | No |
| Ease of Expansion | Easy | Limited |
| Lifespan | 15-25 years | 10-15 years |
| Warranty | 15-25 years | 5-10 years |
| Single Point of Failure | No | Yes |
When to Choose Microinverters
Microinverters are ideal when:
- You have partial shading (trees, buildings, chimneys)
- Panels face different directions (e.g., east and west)
- You want panel-level monitoring and diagnostics
- You plan to expand your system over time
- You have a complex roof layout
- Budget allows for higher upfront cost
When to Choose String Inverters
String inverters are ideal when:
- All panels face the same direction with no shading
- Cost is a primary concern (lower upfront cost)
- Simple installation (all panels in one location)
- System size is large (5kW+) where cost difference matters
- Easy access to inverter for maintenance
Cost Comparison Example
800W System (4 × 200W panels)
| Component | Microinverter | String Inverter |
|---|---|---|
| Panels (4 × 200W) | $600 | $600 |
| Inverter(s) | $320 (4 × $80) | $150 (1 × $150) |
| Mounting & Cables | $200 | $250 |
| Total | $1,120 | $1,000 |
* Microinverters cost ~$120 more but provide better shading performance and monitoring.
Performance with Shading
This is where microinverters really shine:
Scenario: One panel is 50% shaded in a 4-panel system
- String Inverter: All 4 panels drop to 50% output (weakest panel limits the string)
- Microinverters: Only the shaded panel drops to 50%, other 3 panels operate at 100%
Result: Microinverters produce ~87.5% of normal output vs 50% for string inverter.
Popular Brands
Microinverters
- Enphase IQ8 Series (most popular)
- APsystems QS1
- Hoymiles HM Series
String Inverters
- SMA Sunny Boy
- Fronius Primo
- SolarEdge (with optimizers)