Houston joins San Francisco, San Jose, and Elk Horn, Iowa, in making it easier for electric-car owners to fuel up. Photo: CalCars

Reliant Energy is converting 10 Toyota Prius gasoline-electric hybrids to plug-in electric and installing 10 recharging stations, most of which are available to the public, throughout Houston.

Though the city won't charge for electricity, drivers must buy a $10 pass key. In addition to text-messaging or e-mailing subscribers when their vehicle is done charging, Coulomb Technologies' password-protected ChargePoint Network allows drivers to find unoccupied stations via Web-enabled cell phones.

“We expect the lessons learned from the pilot program to enable us to make better decisions for future infrastructure investment,” says Houston's Assistant Finance Director James Tillman, who estimates each converted Prius will save the city $1,400 annually.

Of the city's 12,500 vehicles, 750 are gasoline-electric hybrids such as the Ford Escape, Chevrolet Malibu, Club Car Carryall, Toyota Camry, and Toyota Highlander.