System Components & Design

A central inverter that converts the combined DC output of one or more module strings to AC; cost-effective but limited by the weakest module in a string.

A small inverter mounted at each module that converts DC to AC at the module level, improving performance under shading and allowing per-module monitoring.

A module-level DC-DC device that performs MPPT per module and sends optimized DC to a central string inverter.

Regulates current and voltage from the array to the battery, preventing overcharge and (in many units) over-discharge.

PWM controllers pull array voltage down to battery voltage (simple, lower cost); MPPT controllers convert excess array voltage into extra charging current (more efficient).

The percentage of remaining usable capacity in a battery, from 100% (full) to 0% (empty).