The Oklahoman reported last week about a movement out of Oklahoma City to get the United States Postal Service to switch from gasoline and diesel to natural-gas-powered vehicles. Natural gas is cheaper than either of those two fuels right now, which would be good for the USPS, but the real story here is in the power of demand. In this video, Fool.com contributor Aimee Duffy takes a look at what would happen if the Post Office pursued this idea.

Fool contributor Aimee Duffy owns shares of Ford. Fool contributor Tyler Crowe owns shares of Westport Innovations. For more energy information, follow them on Twitter @TMFDuffy and @TylerCroweFool.

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