The Plug-in hybrid electric vehicles combine the best of electric and hybrid-drive technologies.What is more, these plug-in hybrids should not be much more complex, heavy or pricey than present hybrid models. First, their internal combustion engines will shrink as their electric motors and batteries grow. Second, batteries and electronic
components have been steadily dropping in price.
A conventional auto costs about 12 cents a mile to operate at current gasoline prices. A plug-in hybrid could run on electrons at three cents a mile using electricity costing about eight cents a kilowatt-hour, the current average residential rate. And given that half of American cars travel only 25 miles a day or less, a plug-in with a battery capable of providing power for a 20-mile range could cut petroleum-based fuel consumption by as much as 60 percent. Even a long-distance commuter driving a plug-in hybrid could go most of a typical day on less expensive electricity stored in an advanced batter that was topped up overnight via a conventional wall socket and partially recharged at work during the day.
Today Plug-in hybrids offer other unique benefits.One can speculate that a utility might lease a plug-in hybrid to a consumer or business willing to leave the vehicle connected when it was not on the road and to permit the utility to control when the vehicle's batter was charged and discharged depending on its generation or voltage-regulation needs. Such an arrangement would help utilities with load balancing, for instance.
For policymakers concerned about global warming, plug-in hybrids hold an edge over another highly touted green vehicle technology -- hydrogen cars. Plug-ins would be better at utilizing zero-carbon electricity because the overall hydrogen fueling process is inherently costly and inefficient. Any effective hydrogen economy would require an infrastructure that could use zero-carbon power to electrolyze water into hydrogen, convey this highly diffuse gas long
distances, and pump it at high pressure into the car -- all for the purpose of converting the hydrogen back into electricity in a fuel cell to drive an electric motor. The entire process of electrolysis, transportation, pumping and fuel-cell conversion would leave only about 20 to 25 percent of the original zero-carbon electricity to drive the motor. In a plug-in hybrid, the process of electricity transmission, charging an onboard battery would leave 75 to 80 percent of the original electricity to drive the motor. Thus a plug-in should be able to travel three to four times farther on a kilowatt-hour of renewable electricity than a hydrogen fuel cell could.