For the non-engineers out there who are interested in learning asmuch as possible about how solar panels work, here’s a brief overview of micro-inverters and what they can add to a solar installation.
Solar panels need (micro)inverters to convert the electricity they produce to a type that can be used at home. Solar photovoltaic panels produce DC (direct) electrical current, andhousehold appliances use AC (alternating) electrical current. AC and DCrefer to the direction that electrons flow when electricity is created.Technical details aside, the key point is that electricity produced bysolar panels must be converted from its raw form to a more usable one.Inverters make this conversion possible.
Micro-inverters perform this energy conversion for individual panels or small groups of them, not for the entire system. Traditionally, a solar system would have one inverter for all of the panels, whichlimits the amount of equipment needed. However, micro-inverters offer a definite efficiency advantage. Here’s why: With a traditional inverter, the solar system can onlyreach the efficiency of the least efficient panel. Efficiency can varybecause of dirt on the panels, shading, or mechanical malfunctions. Ifeach panel has its own inverter, however, all can operate at theirmaximum possible efficiencies, optimizing the amount of electricityproduced in the whole system.
Rapidly improving micro-inverter technology has enabled the growth of “plug and play” solar systems, like the Clarian Sunfish, which was recently profiled in the New York Times. This product and its competitors offer very small scale solar panel systems that can simplybe plugged in to start generating electricity, bypassing a more complexinstallation process.
Micro-inverters are used less frequently for larger commercial orutility scale projects, although there is an ongoing debate over whether or not they should be. For more detailed information on wheremicro-inverters and traditional inverters are best used, check out theRenewable Energy World podcast Microinverters vs. Central Inverters: Is There a Clear Winner? along with Greentech Media’s article Can Micro-Inverters Penetrate the Megawatt-Scale PV Market?
Technology in this area will continue to evolve. It’s a fun topic to follow.