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Microinverter vs String Inverter – Complete Comparison

Which inverter type is best for your balcony solar system?

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.

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)

Frequently Asked Questions

Can I mix microinverters and string inverters?

Not recommended. Each system should use one type consistently. However, you can have separate systems with different inverter types if they're on different circuits.

What about power optimizers?

Power optimizers (like SolarEdge) are a middle ground - they attach to each panel but feed a central inverter. They provide some shading benefits of microinverters at lower cost, but still have a single point of failure.

Which lasts longer?

Microinverters typically last longer (15-25 years) because they're mounted on panels (cooler) and have longer warranties. String inverters in hot locations may need replacement after 10-12 years.

Can I upgrade later?

With microinverters, you can easily add more panels with their own microinverters. With string inverters, you're limited by the inverter's capacity and may need to replace it to expand.

Calculate Your Solar System ROI

Use our calculator to see your savings and browse recommended inverters, panels & accessories

What you'll get:

  • • Free ROI calculator with PVGIS data
  • • Recommended microinverters (Enphase IQ8M)
  • • Solar panels & complete system kits
  • • Cables, connectors & mounting hardware
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