Rental firm Hertz has released figures detailing the fuel efficiency of its fleet--and it's now the most fuel-efficient in the rental industry.

Along with efforts to introduce hybrid and electric vehicles to the company's rental fleet, Hertz is benefiting from general increases in new vehicle fuel economy--which averaged 25.4 mpg in March.

The company says 78 percent of its vehicles now attain 28 or more miles per gallon on the highway.

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While that implies combined mileage is lower, Hertz tells us that its vehicles track closely with CAFE standards--so a number not unlike the countrywide average is likely.

More interesting is Hertz's fleet of hybrids, which grew 55 percent last year. People are driving those hybrids more too--the company tells us that year-on-year hybrid miles driven has increased by 82 percent, a result of growing popularity in both corporate and leisure rentals.

Regular cars capable of 26 mpg combined or more are also being driven further, increasing by a fifth in 2013 compared to 2012. That shows that higher-mpg cars are actually being driven, rather than sitting in fleets unused.

That figure has allowed Hertz to pass the green threshold for Smart Way 2014--the EPA's excellence awards for businesses leading the industry in efficiency and sustainability.

Increased use of electric vehicles should improve that further in the coming years.

Hertz now has several electric cars on its fleet, from the Tesla Model S to more humble offerings like the Nissan Leaf, Chevrolet Volt and Chevrolet Spark EV.

They're currently offered at ten different locations around the country--several of which are in California--but in the coming months, Hertz says it will offer electric vehicles at nearly every major airport location. The Spark EV, for example, was added at San Francisco and Los Angeles airports, and selected rental spots in late May.

Taking a holistic approach to reducing waste and emissions, Hertz also uses waterless car washing at more than 220 locations and produces more than 2 million kilowatt hours of solar energy every year.

If you already own a fuel efficient car and aren't keen on trading down next time you're in a different part of the country, it's good to know you can get your hands on something fuel-efficient--or even electric-powered--once you arrive.


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