String inverters are connected to series of panels. These inverters collect the accumulated DC Voltage and convert the Direct Current of the installed solar array into grid supportive AC power. Even though these inverters don’t have a number of components for failure, generation depends on the least generating module in the series. Due to shadow issues or low performing module of the whole series generation gets affected. This system best suits on the roofs where there are no shading issues due to trees, adjacent buildings etc.
An alternative solution for the string inverters is Micro inverters. In these systems, each module is connected to an inverter which typically is connected just below the panel. With each panel having one inverter avoids the dependency on other modules generation. Each panel will be independent of each other. This kind of system best suits in a place where there are shadow issues on one or more modules, roof with different directions etc. In this kind of systems, module level monitoring is possible. It helps in easy maintenance of the system. One module or one inverter failure wouldn’t affect the generation of rest of the system.
, even though they offer the same solution of what is offered by micro inverters are little different in electronics technology part. In these systems, each module is connected with one power optimizers. These optimizers start’s tracking MPPT at lower voltages. This helps in generation of power even in low light and intense shadow conditions as well. Each of these optimizers sends the DC output to the string inverter at the end, after optimizing the output of each module individually. With these optimizers, more electronic parts are not allowed on the rooftop. Optimizers can be configured in such a way that one optimizer can be connected to one module or two modules decreasing the cost of the over all system.