Grouped into the category of Module Level Power Electronics, both solutions aim to overcome the deficiencies found with the traditional central inverter systems, which can suffer massive power losses when one panel in the chain is shaded or malfunctions. Additionally, both claim to improve the power yield of solar modules by up to 25%.
So let’s break it down:
With a traditional inverter system, PV panels are wired together like a string of christmas lights, collecting energy from the sun and dumping it into a central inverter system, which then converts the DC electricity to AC. While this might sound simple enough, if a panel in this system experiences any issues, the entire energy output of the system is dragged down.
To avoid this energy loss, microinverters such as the Enphase 215W or the APS YC500A, are installed on each (or every other) panel, decentralizing the conversion of DC to AC from a single point to smart web of panels
Optimizers, such as the SolarEdge 3kW SE3000A-US-U, are similar to microinverters in that they are also located on each (or every other) panel. Instead of converting the energy at each panel, however, an optimizer “conditions” the DC electricity before sending it to a central inverter, mitigating the energy loss that might occur on individual panels, which can drag a whole system down.
The benefits of optimizers is that since don’t convert the DC to AC on each panel, they include less parts than microinverters and are considered easier to install and scale. Conversely, since optimizers feed the DC electricity into a central inverter, if that inverter goes down the entire system can fail, whereas a failure with microinverters only affects one module.
Ultimately, the deciding factor on which MLPE to go with depends on the specifics of one’s home. Optimizers are good for harsher weather environments and micro-inverters are good for a home with panels that need more independent control.