US News and World report published a long article on PHEVs on October 9: http://www.calcars.org/­calcars-news/­536.html. (You can see a PDF of the story at http://www.calcars.org/­downloads.html.) Under the heading, "Goodbye, Gas Guzzlers," the October 23 print edition of the magazine includes four letters in response. They are unusually well-presented.

I'm thrilled to see the coverage of battery-powered vehicles in U.S. News. You finally delivered news about electric-powered cars' promise: low/no emissions, low-cost driving, and energy independence ["A Plug for Hybrids," October 9]. I rented and drove a GM EV1 battery electric vehicle six years ago and fell in love with its well-appointed, powerful elegance. Upon finding that none of the six major automakers building EVs actually sold them, I became an Evangel (EV activist). I'm still pushing automakers to mass-produce zero-emissions vehicles as the alternative that will make it happen someday soon. -- Hugh E. Webber, Winter Park, Fla.

Since 2001, I have owned two Prius hybrids and have found that the mileage realized is even better than advertised. During a recent vacation in Europe, I discovered that every Prius there has an "EV" button (electric vehicle) on the dashboard that allows a driver to use the "battery only" for shorter trips. Someone should ask why this gas-saving feature is absent on Prius cars sold in the United States. Plug-in hybrids are a reality, and further "research" to prove their practicality is not necessary. Philanthropists and governments need only subsidize conversions, guarantee all parts of the manufacturer's warranty, and subsidize replacement batteries if and when they are needed. -- Richard Rosenbaum, Bloomfield Hills, Mich.

The proponents of plug-in hybrids certainly have the best intentions, but the road to hell is paved with good intentions. If gasoline or diesel fuel consumption were reduced, how would we pay for roads when fuel tax collections would decline from the use of plug-in vehicles? Would battery charging be subject to a fuel tax? -- A. Trujillo Escareno, Tustin, Calif.

In "A Plug for Hybrids," Kateri Callahan, president of the Alliance to Save Energy, is quoted as saying PHEVs are "the most immediate and practical alternative to petroleum." Then why are there so few of these 100-miles-per-gallong cars on the road? It is because industry won't produce them, and for good business reasons. First, the added cost of the high-energy battery will limit the market; second, battery life and performance are still unknown. But industry will never know how these batteries perform until we get a few thousand PHEVs on the road operating under real-world conditions. Congress needs to step up to the plate to break the impasse. I propose a new kind o f contract with America involving the American people, both political parties, and industry to create the incentives needed to put millions of PHEVs on the road in the next 10 years. Robert M. Phillips, Emerald Hills, Calif.