One thing these guys have seemed to have forgotten....carbon....conducts electricity, and they're going to have a cable from GEO to the ground. Rotating along with the Earth within a giant magnetic field....what happens when you get a conductor rotating within a magnetic field....that's right, an electric current. With this one, a massive electric current, commensurate with the potential difference between both ends. In this case trillions of volts!!!!!
Unless the nanotubes have the same conducting qualities as graphite and they layer the crystals of the carbon nanotubes carefully and in the right orientation, they'll get the biggest shock (pun intended) they'll ever see.
If I remember correctly, the strength in carbon nanotubes runs longitudinally along the carbon atom lattice, in which case they wont act like graphite at all. They'll be a very good conductor of electricity. If they could handle the voltages involved, they could use the power generated within the cable to power their carriages on the elevator and also to power the countryside below.
