Brace yourselves everyone: Computer Science/Tech person about to rant about wiring.<br/><br/>Copper is used for most, however, places that need a lot of bandwidth (tech companies, companies that do video streaming, companies that have websites that people access a lot, etc) have probably spent the money to get fiber optic, which is glass or silica. Copper wiring is also considered to be hazardous as the old copper cables get old and need to be replaced, that said, it still conducts electricity really damn good. So what I'm saying is, it's GM discretion just how much havoc she can play with the power grid.<br/><br/>I swear to god, if unbridled use of Penny's powers knocks out Tulane Medical, Penny and Tina will have words. Very strong words. Punctuated by blasting noises.