it can't be "nuke or solar." it will have to be a combination of the two. we could nearly eliminate gas/diesel powered autos/trucks in a matter of a few years. build a series of nuclear plants across country to power electric interstates slotted exactly like the tracks we plugged up & ran our toy electrics. build elec. powered vehicles with backup batteries big enough for 250 miles for when on backroads. the French (of all people) have led the way in small-scale nuclear plants. they came up with a simple design, and built a buttload of them identical. cheaper by the dozen, economy of scale... most folks would eventually end up with a solar charging station at home for private vehicles. maybe cover the outside of the auto in photoelectric paint so your battery would charge as you drove, on a pretty day?