|MadSci Network: Engineering|
Well, Greg, the problems are all those of making an electric car, plus the problems that come from having the sun be your energy source.
The latest electric cars are very light in weight. They would use high energy density rechargeable batteries. They use AC induction motors and variable frequency drives. They even use regenerative braking. This means you brake the car by having the motors turn as generators and pump power back into the batteries at high speed, and finish the braking to a halt with conventional disk brakes. This will conserve what little energy (by comparison to gasoline) they carry.
The best solar cars would have these items. A battery bank is needed because you wouldn't want the car to stop just because the sun went behind a cloud. The solar electric source would be as many photovoltaic cells as you could fit onto the car as feasible. These are still expensive and about 10% efficient. Here's a California State University link you can try with a lot of information you can sample:
Good luck in your research!
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