In part 1 of Using Natural Gas as a Transportation Fuel we looked at the basics of using natural gas in your car or truck vs. using gasoline derived from oil. The main reasons for considering natural gas are that the U.S. imports much less natural gas than it does oil and that natural gas burns much cleaner than gasoline (derived from oil).  To use natural gas in a vehicle, you have to use compressed natural gas.  There are federal incentives for natural gas vehicles and there may be natural gas vehicle incentives available for your state. One of the only cars available to consumers that uses compressed natural gas is the Honda Civic GX.  In fact, it was just named the 2011 greenest vehicle list by the American Council for an Energy Efficient Economy - even greener than plug-in electrics like the Nissan Leaf!

Consumer Reports has a great review of the pros and cons of driving a natural gas vehicle.  One of the pros from Consumer Reports:

The cost of CNG can be as little as half that of a gallon of gas if you use a home refueling device. And at commercial stations, the cost is still less than gasoline. Some research pegs the fuel savings at about 30 percent less than gasoline on average.

The biggest challenge for those choosing the fill up their vehicles with natural gas is the same challenge that early adopters of plug-in electrics will face: how to fill up their vehicles and overcome range anxiety.  The advantage that gasoline (derived from oil) has is that the infrastructure is in place to fill up just about anywhere you need to.  With electric vehicles and natural gas the infrastructure is  not in place, so you have to do a little more planning ahead of your trip to ensure you'll have enough juice to make the journey.  Of course, with plug-in electric hybrids you can rely on gasoline as a backup so you don't have to worry about range anxiety, but natural gas vehicles don't have that luxury. With compressed natural gas vehicles, you have two options to filling up:

1. Fill up at home with a produce like the Phil compressed natural gas filling station
2. Find a compressed natural gas filling station (warning: many of the locations in the map are for private or government filling stations - with the exception of those in California)

So while you may pay less for actual natural gas than you will gasoline, you may pay higher upfront cost (for the home filling station) and you may have a little more trouble finding a filling station on the road (which is the same dilemma that will initially be faced by plug-in electrics).  And all of this assumes that the U.S. will have an abundant supply of natural gas for the near future (which it is projected to have). When deciding if a natural gas vehicle is right for you, you have to ask yourself one question: Do you value a cleaner solution to powering your vehicle and one that doesn't require the U.S. to be held hostage by despotic regimes?