Sarah, The problem with doing what you want isn't just generating capacity. You're talking about increasing the total load on the power grid by a factory of somewhere around 15-20 times to supply 100% of the power used in transportation. Do you have any idea how much money will have to be invested in overbuilding the electrical power grid? The power grid is a lot more than just wires and towers.
Before you and others start advocating ideas like this, you need to stop and consider what the consequences would be to the rest of the economy.
Jack