If you're planning a summer vacation to a U.S. national park this summer, you may start to see a few changes when you get there.

The U.S. Department of Energy's (DOE) Clean Cities program and the National Park Service (NPS) recently announced nine new projects to deploy green vehicles within nine of the 13 national parks.

The nine parks--stretching from Maine's Acadia National Park to Utah's Zion National Park--will replace conventional internal-combustion vehicles with low- and zero-emission alternatives, including propane-powered trucks and vans, low-speed electric vehicles, and plug-in hybrids.

A complete list of the projects is available on the DOE website.

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Theses latest projects are part of an ongoing initiative by the NPS and DOE to increase the use of alternative fuels and advanced-fuel technologies in national parks.

Park ranger charges a Chevrolet Volt at Golden Gate National Recreation Area

Park ranger charges a Chevrolet Volt at Golden Gate National Recreation Area

The agencies previously estimated that cleaning up park service vehicles could save 10,000 gallons of gasoline and cut 71 tons of greenhouse-gas emissions per year.

The Clean Cities program and NPS also created a set of educational materials to encourage visitors and staff to drive more efficiently.

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After all, cleaning up a park's fleet of service vehicles will only help so much if visitors still create lines of idling cars every weekend.

It's estimated that if just 25 percent of the average seven million annual visitors to the 13 national parks reduced their idle time by five minutes, it would save 192,000 gallons of gasoline and cut 2,000 tons of greenhouse-gas emissions per year.

Meanwhile, those visitors that choose to tour a national park in electric cars have issues beside traffic to deal with.

Electric-car charging stations are limited in the parks, and without stations on the roads that lead to the parks themselves, a long-distance return trip may not be possible if the charging stations are fully occupied.


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