Solar Micro-inverter

A solar micro-inverter, or microinverter or micro inverter, converts direct current (DC) electricity from one or two (depending on manufacturer) solar panels to alternating current (AC). The output from several micro-inverters is combined and often fed to the electrical grid. Micro-inverters contrast with conventional string or central inverter devices, which are connected to multiple solar panels.

Micro-inverters have several advantages over conventional central inverters. The main advantage being small amounts of shading, debris or snow lines on any one solar panel, or even a complete panel failure, does not disproportionately reduce the output of the entire array. Each micro-inverter harvests optimum power by performing maximum power point tracking for its connected panel. They are also simple to design and stock, as there is normally only a single model of inverter that can be used with any size array and a wide variety of panels.

Their primary disadvantages include a higher initial equipment cost per peak watt than the equivalent power of a central inverter, and increased installation time since each inverter needs to be installed adjacent to a panel (usually on a roof). This also makes them harder to maintain. Some manufactures have addressed these issues with panels with built-in micro-inverters.

Micro-inverters that accept DC input from two solar panels, rather than one, are a recent development. They perform independent maximum power point tracking on each connected panel. This reduces equipment cost and makes photovoltaic (PV) systems based on micro-inverters comparable in cost with those using string inverters.