Commentator Bob Bruninga would have us believe that electric cars could substantially increase the energy efficiency and decrease the environmental impact of autos while providing an economical and practical alternative to our current gasoline-fueled fleet ("Keep on open mind on electric cars," Oct. 4). Nothing could be farther from the truth.
Let's look at energy efficiency. The gasoline-fueled internal combustion engine has an efficiency rate of about 25 percent, while diesels have an efficiency rate of 30 percent. This isn't very impressive, to be sure, since electric motors can have efficiency ratings of 90 percent or higher.
However, let's consider the entire energy chain. A battery needs to store all its chemical energy internally. This is why our best lithium ion battery can store only a small fraction of the energy of a gallon of hydrocarbon fuel.