Quick Summary
A string inverter is a central wall-mounted box that connects a series (string) of solar panels together. It is highly efficient and budget-friendly for unshaded roofs, but if one panel in the string is shaded, the entire string's output drops.
To overcome string constraints, companies like SolarEdge add **DC Power Optimizers** to the back of each panel. Optimizers adjust the voltage of each module before sending it to the central inverter, giving you shading protection similar to microinverters.
String Inverter Pro/Con Balance
- Pro - Lower Equipment Cost: Sizable upfront savings compared to buying 25+ microinverters.
- Pro - Centralized Maintenance: If the inverter fails, it is located on the wall, not on the roof.
- Con - Single Point of Failure: If the central inverter fails, the entire system stops generating power.
Frequently Asked Questions
How long does a central string inverter last?
Most string inverters last 10 to 15 years and will need to be replaced once during the 25-year lifespan of your solar panels.