Why Not Quantify Potential U.S. Ground Transportation Electric Energy Use?

What is the total energy needed to power all American cars in regular use at any given time? If all of the cars were electric how much power would be need in watts?

Super-conducting power lines can store electricity indefinitely. Electricity input to a national transportation line to let electric cars recharge directly while under way could be produced from a number of wind and solar technologies. The most expensive in energy use element may be to produce liquid hydrogen or nitrogen to cool super-conductors to a couple hundred degrees below zero-since room temperature super-conductors aren't yet existent.

Would the energy cost to manufacture and cool super-conducting lines on U.S. interstate highways be less than, equal to or greater than the cost of buying foreign gasoline, carbon emissions, opportunity cost for outsouring cash for the energy to power American cars? These are useful questions to consider, an examples way the U.S. government, and even state governments, have a role in choosing and supporting what directing U.S. economic and energy policy takes. Few individuals could for-themselves make a transition to a new national ground energy and transportation structure.