Hybrid sales are surging these days, but renting one is still frustratingly difficult, mainly because of scarcity. Enterprise, the country's largest rental-car agency, owns 7,000 of the green rides—far more than its rivals—but that's still a skimpy 1 percent of its fleet. Here's how to increase your chances of scoring one:
Surf high and low
Kayak has the most extensive hybrid listings of all the travel booking and aggregator sites (it checks six rental agencies), but you will see the vehicles under "car options" only if there's one available at the location you specify. You can also search directly on the rental-agency sites, but you need to know where to look: Avis, for example, lists hybrids as "specialty cars"; Hertz groups them under its "green collection."
Hold agencies to their word
Hertz, Avis, and Budget say they guarantee hybrid reservations—but that guarantee goes out the window if the stock isn't there. If the car you want doesn't materialize as promised, try one of these tacks: Ask the desk agent to rent you another vehicle temporarily and to deliver the hybrid to you as soon as it's available. Or, request a coupon for a future rental as compensation. Agents won't give them out unbidden.
Drive one off the lot
No luck with the agencies? Go to a Toyota dealership instead. About 75 percent of the company's 1,200 outfits nationwide rent their cars, but not all of them have hybrids, so you'll have to call ahead to make sure there's one available at your destination. (Dealerships that participate in the program are listed at toyota.com/rental.) The hybrid rentals start at around $50 a day, which is similar to what the major agencies charge in certain cities. A bonus: Some dealers even have a free shuttle service to pick you up at the airport.
Keep your speed in check on the highway: Driving fast burns more fuel and causes greater emissions. In a typical family sedan, every 10 miles per hour you drive above 60 costs you an extra 54¢ per gallon at the pump.