Conductors Conduct Electricity Very Well

In an insulator, the firme level sits exactly in the middle of a band gap. A band gap means there are no available electron energy levels in this region of energies that corresponds to where the firmi level is. So you don't get uch conducta much conduction of current in insulators. In order to conduct electricity, what you'd have to have is an electron excited all the way over the band gap,. up to higher electron bands which exist at much higher energy levels. But because there's such a big gap between where the electrons actually are and where they would need to be in those higher energy levels it's very unlikely, very unusual, for that to happen.