In a comment to the blog HOT AIR Romeo 13 posted an analysis of how much additional electric power would be reqyuired if the nation went entirely to Electric cars. He asked for someone to check his numbers, so I did, and they were about the same as what I computed. But, I couldn't get access to post a comment. This is an interesting question, so here is my analysis:

Gasoline consumption in the US is about 390 million gallons per day. Gasoline has about 125,000 BTU per gallon. 3413 BTU = 1 kW-hr. There are 365 days in a year. Putting this all together we get that 5.22 trillion kW-hr is used in trnsportation each year. Electric power consumption is 4 trillion kW-hr per year. Thus we would need 130% more electricity each year for all transportation to be electric. One could argue that it would not take this much additional installed power generation capacity since the car batteries could be re-charged during off-peak periods. Nevertheless, it would take a huge investment to double the entire elecric power generation capacity in the US. THis is not a solution that could be implemented in 10 years, or even 20 years.