Oh but it was electrified.
If you recall, at least in the book (I haven't seen the Movie), the great invention of Mr Galt, was the Static Charge Motor, that could take its electrical energy right out of the static charges placed in the air. Though I don't recall it going 300mph in the book. But that was a lot of years ago - I read the book while in college.
That part of the book had a sort of science fiction flavor to it. But I don't think it quite qualifies as science fiction in general - because it wasn't a new idea. After all, Nicola Tesla, a noted and very important electrical engineer and inventor, had already experimented with similar ideas, years before Ayn Rand wrote Atlas Shrugged.
Unfortunately, his experiments were hampered greatly by the great fear they caused in the general populous. Imagine the public angst to be had at the thought of great quantities of electrical energy just zapping though thin air - scared the hell out of a lot of people! He was often viewed as a "Mad Scientist", in spite of the fact that he is literally the father of our modern electrical power distribution system - as it stands now.
Nikola Tesla
It still doesn't take a tenth of a tenth of a new idea, to provoke the same fear now!
Even with old well proven, but forgotten ideas!