What I mainly took issue with was the conclusion: "Thus, alternative energy sources must approach the energy density of petroleum if they are to be competitive.

What I mainly took issue with was the conclusion: "Thus, alternative energy sources must approach the energy density of petroleum if they are to be competitive." That seems utterly faulty to me, as I pointed out - there are multiple ways to solve the problem, none of which would necessarily require increasing the energy density of alternative power sources. All you have to do is reduce the amount of energy that needs to be stored in the vehicle, either by reducing use or required range between charges. For what it's worth, there are already ways to beam energy to moving cars. http://www.extremetech.com/extreme/101581-inductive-car-charging-no-plugs-or-exposed-wires-no-muss-no-fuss http://www.extremetech.com/extreme/101581-inductive-car-char...