The economics involved in achieving pollution-free vehicles, as projected through the end of the century for both exhaust-suppressed combustion engines and electric powerplants, points to battery-operated cars as ultimately the less expensive means of curbing automotive emissions. However, it is predicted that all-electrics will outnumber combustion-engine vehicles after the start of the 21st Century, at the earliest, and then only at the price of mediocre top speeds and performance when using nonhazardous batteries.
Unlimited range electric cars will become possible with the rapid replacement of depleted batteries at service stations, eliminating the need for recharging at home by drivers. To close the 30-year gap between quantity production of all-combustion and all-battery automobiles, a hybrid vehicle concept is described, whose power system consists of a small turbine, generator, electric motor and batteries.