|MadSci Network: Engineering|
Hello....Robert! In a car driven by electric motors, the electricity must come from some source. These can be things like: a. overhead wires (as trolleys use) b. batteries only c. a small engine using chemical fuel charging a much smaller (and lighter) battery than in option b. The first of these involves creating a very large amount of infrastructure that does not currently exist. The second is used, but the range and power capability of the vehicles is limited. Presently this limitation is such that the vehicles don't find much favor in the marketplace. The third is the basis of hybrid-electric cars, and it is starting to find favor in the market. Several are already for sale. A car powered by fuel cells also falls into this category. Scientific American recently (last few months) published a long article on exactly this subject, comparing many ways to power vehicles. You should certainly look at that article.
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