Imagine a world in which virtually all private and public transportation is powered by computer-optimized electric motors except for the largest diesel engines and aircraft. With the prospect of some promising near-term improvements in battery storage technology, it's time to assess what obstacles to such an idyllic future remain to be surmounted.

Every other aspect of electric motorized transportation is well within the reach of current technology. If the electrical power required for charging the batteries were not merely generated by burning hydrocarbon fuels at a location other than the automobile, the most significant remaining emitters of greenhouse gases would be people and cows. The mountains of money sent to the despots and dictators that now profit from America's dependence on oil could then help our own economy. Food could be grown for eating instead of burning. All that remains is to figure out where so much electricity might come from.

Now imagine that you are in the market for an electric motor to replace the gas-guzzling internal combustion engine that powers your car. Before you make the switch, you're certain to ask: How much electricity will have to be purchased from the power company to take an otherwise identical car as far down the road as it used to go on a gallon of gasoline? Call it the gasoline equivalent electricity. An optimistic estimate--based on the fuel mileage and engine power of our existing fleet of compacts and sub-compacts, and taking into account such factors as the ability of electric motors

Now, the cost of a KWh varies considerably with the amount used. Indeed, electricity is the only commodity I know of whose retail price increases the more you use it. My own electricity provider, Southern California Edison, charges a minimum of $0.30 for every KWh used beyond a baseline amount, after adding all the taxes and surcharges. So, the net conclusion of this exercise is that to replace a gallon of gasoline for cars that average around 30 mpg, drivers will have to pay the electric company $12 per equivalent gallon. This number goes up rather rapidly for larger or multiple cars. Clearly, this is unacceptable even with gasoline over $4 per gallon. We have technology for electric transportation. What is needed is technology for much cheaper electricity.

In an opinion piece recently published in the New York Times, Thomas L. Friedman, without any reference to the rudimentary calculations provided above, suggests that the idyllic world of electric transportation is nearly upon us. Citing the perils of climate change, the Obama administration has made alternative "green" energy and motor vehicle fuel efficiency a priority for infrastructure and research spending. Without offering an opinion on the scientific basis of global warming theory, an intelligent effort in that direction would at least attempt to free us from an economically damaging dependence on the petroleum industry and foreign cartels. Because 50 percent of petroleum consumption goes to private vehicles and another 20 percent to heavier trucks, trains, buses, and machinery that can potentially be converted to electrical power (with the remaining 30 percent going to aircraft and industrial uses that cannot), there is at least a theoretical possibility that the United States could provide all its future petroleum needs from much cheaper domestic sources.