This article describes an innovative movement by Kenworth. Operating vehicles with compressed natural gas or liquefied natural gas can offer improvements to emissions quality along with the dual ability to operate in either Otto Cycle (gasoline) or Diesel engines with some increased amount of exhaust gas recirculation (EGR).
Another benefit to operating on natural gas is the increasingly competitive prices between diesel fuel and natural gas. Of course, we cannot assume that these prices are in a fixed trend, but for the foreseeable future this makes sense.
During a study abroad experience in Argentina, I witnessed firsthand the operation of many automobiles that run on compressed natural gas. But unlike Kenworth, whose important plans include using LNG for large diesel trucks, compressed natural gas in Argentina was used in the tiniest of cars (there were not too many large trucks in Argentina like there are in the United States). These cars were specially outfitted to accept this form of fuel, and there were many stations around the country specially labeled for their distribution of GNC (gas natural compresificada).
One glaring obstruction to this implementation in the United States is the lack of a supporting infrastructure to enable the technology to prevail. If I drove my natural gas vehicle around town, I don't know if I would have anywhere to fill up. However, with a concerted grassroots effort, we can help develop this technology here in the United States, and provide a cleaner alternative to our addiction to oil.