Solar Insights

Microinverters vs. String Inverters: The Battle for Your Roof

Should you choose Enphase or SolarEdge? We compare the two dominant inverter technologies to see which one offers better efficiency, safety, and reliability.

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The Brains of the Operation

Your solar panels produce DC (Direct Current) electricity, but your home runs on AC (Alternating Current). The device that makes this switch is the Inverter. Is it better to have one giant brain on the wall (String Inverter) or dozens of tiny brains on the roof (Microinverters)?

This is the “Android vs. iPhone” debate of the solar world.

1. String Inverters (The Old Guard)

How it works: All your panels are wired together in a series (like old Christmas lights) and plugged into a single box on the side of your house.

  • Brands: SMA, Fronius, Tesla.
  • Pros:
    • Cost: Significantly cheaper. Fewer components.
    • Maintenance: The inverter is on the ground. If it breaks, the technician fixes it at eye level. No roof climbing.
  • Cons:
    • The “Christmas Light Effect”: If one panel is shaded by a tree, the entire string’s performance drops to match the weakest link. (Note: DC Optimizers mitigate this, but add complexity).
    • Single Point of Failure: If the inverter dies, your entire solar system produces zero power.

2. Microinverters (The Modern Standard)

How it works: A small inverter is attached underneath each individual solar panel. The DC-to-AC conversion happens immediately on the roof.

  • Brands: Enphase (Market Leader), APsystems.
  • Pros:
    • Panel Independence: If a bird poops on Panel A, Panel B is unaffected. This is crucial for roofs with complex shading.
    • Safety: AC power runs down from the roof. High-voltage DC is eliminated, reducing fire risk.
    • Expandability: Want to add 3 more panels later? Just plug them in. String inverters are limited by their capacity.
    • Monitoring: You can see exactly which panel is underperforming in the app.
  • Cons:
    • Cost: Roughly 20-30% more expensive.
    • Roof Failures: If one microinverter fails, someone has to climb on the roof and lift the panel to replace it.

The Verdict for 2026

  • Choose Microinverters (Enphase) If: You have a complex roof with multiple angles, chimneys, or trees. The independent optimization is worth the extra cost. This is the choice for 80% of residential homes.
  • Choose String Inverters (SolarEdge/Tesla) If: You have a perfectly south-facing roof with zero shade and want to save money, OR if you are installing a battery system that requires a specific hybrid inverter.

The Golden Rule: Don’t be cheap on the inverter. It is the component most likely to fail. Paying for quality now saves you a headache in Year 10.

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