The biggest mistake this study makes is its naiive belief that plug-ins (and later all-electrics) will only constitute a small portion of the fleet. That's totally absurd - plugs i-ns will usher in a revolution. The other silly estimate the study makes is that plug-ins will still be around in 2050. By then all-electrics will have replaced plug-ins, which are simply a transitional technology that only exists because of the high cost of batteries.