The cells are built that has a clear optical layer below the glass (to Enable Solar in) but seem opaque when viewed from the bottom under. This makes for a far more present day, seamless aesthetic than solar shingles or tiles from CertainTeed or SunTegra. PVLib is surely an open-source https://throbsocial.com/story2492418/5-easy-facts-about-solar-cell-rooftop-described