Traditionally solar panels have been wired in series to a single inverter. This has been simple but has the major disadvantage that if one panel is failing or producing less than the others in it’s string (shade from a tree or roof vent for example)  it drags down the output of all the other panels in the string.

In recent times micro inverters have been developed where each panel has it’s own inverter. This allows each inverter/panel combination to produce power independently of the others, and also allows for monitoring of each panel.  At this time they are a separate item from the panel, but panels with built in micro-inverters are starting to appear although we have not encountered any yet in our area. Although install times would go down, it would seem that if ether panel or inverter failed both would have to be replaced with these combination units.

We see two main brands of micro-inverters in use currently, from Enphase and APS.