All About Solar

SOLAR 101

String inverter, micro inverter or power optimizer?

As we know, the main job of inverters is to convert direct current (DC) energy generated by your solar panels into usable alternating current (AC) energy. After the panels themselves, inverters are the most important equipment in your solar power system.

There are three types of inverter that are the most common used inverters for solar energy system, string inverters, micro-inverters and power optimizers, which is the hybrid of string and micro.

String inverter:

String inverter are the most cost-effective and common type of inverters to be used in solar power system. To simplify, a string inverter is usually the size of a brief case to be installed on a wall. Your solar panels are arranged into groups connected by “strings.” Each string of panels is connected to a single inverter, which transforms the DC electricity produced by the panels into appliance-friendly AC electricity. Here is a tip when you install your string inverter: do not install it where it will be in full sun. You should choose a shaded spot or ask the installer to build a simple shade over the inverter since the direct intense sunlight kills inverters.

Micro-inverter:

Microinverters are installed on each individual panel in a solar energy system. They convert the DC electricity from your solar panels into AC electricity on your roof, with no need for a separate central inverter. In many cases the microinverters are integrated into the solar panel itself, but they may also be mounted next to the panel on the mounting system.

Micro-inverters are rapidly gaining popularity, particularly for residential solar systems, but it tends to be more expensive than string inverters or power optimizers in general.

Power optimizer:

Like microinverters, power optimizers are located at each panel, usually integrated into the panels themselves. However, instead of converting the DC electricity to AC electricity at the panel site, they “condition” the DC electricity and send it to a string inverter. This approach results in higher system efficiency than a string inverter alone.

Due to its ability of offering same benefits as microinverters, but tend to be slightly less expensive, power optimizers are sometimes considered a compromise between micro and string.

 

Reference: Energy Sage, Solar Quote