Two synergistic factors with Musk's other interests, that I'm surprised BW's deep-dive doesn't mention:
* zero-emission cars may make tunnel ventilation a much easier problem
* autonomous cars may far better utilize narrow tunnels (with clearances that'd be too accident-prone for human drivers)
Taken together, tunnels-for-autonomous-fully-electric-vehicles could be far more practical, for longer distances, than they've been for traditional cars.
* zero-emission cars may make tunnel ventilation a much easier problem
* autonomous cars may far better utilize narrow tunnels (with clearances that'd be too accident-prone for human drivers)
Taken together, tunnels-for-autonomous-fully-electric-vehicles could be far more practical, for longer distances, than they've been for traditional cars.