When it comes to power electronics at the module level, the world’s photovoltaic markets are divided. While it is very common for solar technology specialists in the U.S. to install power optimizers (MLPE) in PV systems to meet the relevant installation regulations, these devices are the subject of considerable controversy in the rest of the world. Sweden, for example, has even issued a partial ban on the sale and installation of power optimizers from one major manufacturer because they do not meet the applicable electromagnetic compatibility (EMC) requirements.* So what’s the story with MLPE? What is really technically relevant, and what is just clever marketing? We resolve five common myths about power optimizers.