If you haven’t heard about Elon Musk's recent announcements about Tesla and Solar City’s new solar photovoltaic (PV) roof tile, you must have been living under a rock for the last little while.

It took everyone by surprise, not just because no one expected it, but because it is so good looking in its various design variants. Beyond that, the tiles themselves are toughened glass with what appears to be a metallic sputter coat that makes them directionally opaque but transparent to the…