Natural gas has a few advantages over gasoline. First, it's much cleaner-burning. In fact, the natural gas-powered Honda Civic has the cleanest-burning engine ever tested by the EPA.
The other advantage is that natural gas is plentiful here in the U.S. In fact, we actually export the stuff. So, more cars running on natural gas would mean fewer running on imported petroleum products.
Among environmentalists, enthusiasm for natural gas cars could be hindered by the current uproar over hydraulic fracturing, or "fracking," a process for getting natural gas out of rocks. They fear injecting pressurized water and chemicals into the ground is contaminating the water.
A more immediate problem is simply finding a place to fill up. Natural gas stations aren't easy to find. Also, there's the issue of driving range. Even compressed, natural gas takes up much more space than liquid gasoline. That means you can squeeze in less driving range and -- in the Civic, at least -- the big tank takes up substantial trunk space.
Tesla Motors unveiled a new SUV that the automaker plans to put into production by 2014.
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