Updated: Jul 6, 2020
A solar optimizer is a module that is often connected to a solar panel to optimize its output. They are a counterpart to micro-inverters and solar controllers. Read all about micro-inverters here and solar controllers here.
Their work in a solar system is to increase the system’s total energy output. They do this by constantly measuring the maximum power point tracking (MPPT) of each individual solar panel, adjusting the DC characteristics to maximize energy output and then relaying performance characteristics to a monitoring system for maintenance purposes.
How Optimizers Work
Power optimizers are essentially DC-DC converters. They work by taking the DC power from a solar panel at whatever voltage and current is optimal then converting it to a different voltage and current that best suits the inverter.
They do this using the MPPT. An MPPT, or maximum power point tracker is an electronic DC to DC converter that converts a certain DC from solar panels to the DC needed to charge batteries or to be converted to AC by the inverter. Their use is to extract maximum available power from the panels under certain conditions. In other words, they help increase the MPPT of solar panels.
Microinverters And Power Optimizers
Solar panels produce DC from the sunlight which is then converted to AC by an inverter. When a solar panel is fitted with a micro-inverter, it is then able to produce AC directly. In that case, they become 'AC solar panels' rather than DC solar panels. (Some solar panels come with a factory-installed micro-inverter. These types are referred to as 'AC solar panels'.)
These micro-inverters are designed to be installed one to each solar panel. This is in contrast to the single, standalone, common (string) inverter that is usually installed away from the panels themselves and connected with solar cables. Since micro-inverters are attached to every solar panel, each panel works independently from the rest of the solar array and the DC generated from the sunlight is converted to AC immediately on the roof.
Micro-inverters and power optimizers are counterparts. They are sometimes described interchangeably. They are classed as “Module-Level Power Electronics,” or MLPEs.