|Fig. 1: A Natural Gas Station and Big Rig. Wikimedia Commons)|
Semi trucks have played an important role in getting goods to certain destinations across the US quickly. However, there has been concern over the emissions these vehicles give off, and some are looking for alternative ways to fuel these vehicles that will not only be greener but efficient, in the sense that they still power these big rigs and semi trucks in the same way that diesel is able to.
Production of natural gas may increase as a co-product of oil, or may decrease as a result of higher-cost productive resources. Given the relative inelasticity of natural gas supply in the short term owing to factors such as a 12-18 month lag in the production response to drilling changes, it appears that the effect of oil prices on natural gas demand is dominant in the short run. 
The idea of natural gas is growing in the US. The United States is at the forefront of the rise of natural gas, with hydraulic fracturing and horizontal drilling allowing for access to vast quantities of natural gas and tight oil that was recently inaccessible.  This tight oil boom has rapidly changed the US's role in the global energy market, and looks to have an impact for the coming years. Unconventional gas made up 60% of marketed production in the United States by 2011, and has continued to grow in the years since.  A natural gas fueling station is shown in Fig. 1.
Overall, the concept of natural gas seems like it could catch on in the US. However, there are still many factors to consider in terms of getting more natural gas big rigs on the road. A few reasons why we don't see many natural gas big rigs on the road yet could be because of the high cost and inconvenience to transform diesel engines into natural gas engines, and if natural gas big rigs are not converted but made from the ground up, this could result in much more congestion on highways and freeways. In addition, as of 2014, there were only 1,500 compressed natural gas stations in the United States and only about half of them were open to the public.  This shows that overall, the concept of implementing this system would be a huge inconvenience and would be a very challenging task to take on.
© Jack Richardson. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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