Outside List: Green Car Rentals

Don't blow up your carbon footprint by driving a Jeep Grand Cherokee on your next business trip. Rent green. An increasing number of rental agencies are responding to environmental concerns with green fleets and carbon offset programs. Green-friendly agencies include:

Enterprise Rent-A-Car, Alamo, National
Enterprise has 4,000 hybrids in their fleet, mostly Priuses. Sister companies, Alamo and National have another 1,000 hybrids. The green cars are available in most markets served by Enterprise's 6,500 U.S. branches, though they tend to be concentrated in major metropolitan areas. The company's Keys to Green program offers drivers the option of paying an extra $1.25 per rental to purchase carbon offsets from TerraPass.

Hertz
The Hertz "Green Collection" is a fleet of 3,400 Priuses, which can be requested ahead of time. The agency has also made an effort to add fuel-efficient non-hybrids to the fleet, including Toyota Camrys, Hyundai Sonatas, and Ford Fusions.

Avis
Avis's "Eco Rides" fleet includes Priuses, and hybrid Ford Escapes and Nissan Altimas.

If you're bound for one of the more environmentally conscious corners of the country, there are several small rental agencies with green fleets. In San Francisco, Electric Time Car Rentals has tiny, golf cart-like GEM electric cars. In Maui, Bio Beetle has cooking-oil powered VW Bugs. Fox Rent A Car has a number of hybrids at its West Coast locations.

--Emily Matchar