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The Benefits of Shifting to CNG for Fuel

Adam Smith argued that an enterprise requires a profit to stay in business. He also pointed out that when capacity to produce was less than demand, profits would increase to a point where more capacity got built above the demand required. Trade of excess product could be exported. A fairly recent example of excess capacity occurred a few years back in Singapore where an ice skating rink opened; business boomed and a competitor built a second rink; both went bust. the Wealth of nations is still a good read, if you skip over the statistics on the historical price of wheat in terms of shllings per bushel, and covering several centuries. Right now one ounce of silver buys two bushels; back then there were much greater swings.

Lawyers have been a plague since the days of the hanging gardens of Babylon. Irrigation kept that empire going until the necessity of maintaining the canals ceased to be recognized.

The big difference between a steam powered turbine and an internal combustion engine arises from the heat required to boil water, about half the total heat supplied in the boilers. The result is extraction of about 25 to 30% of the thermal energy as motive power; an internal combustion energy delivers about 40% with gasoline to about 55-60% with diesel fuel. The waste heat in the latter goes out the exhaust pipe.

I use the Energy Information Agency of Dept of Energy to follow crude usage. Refinery inputs are 15 million barrels a day (BOD), of which two thirds are imported, with most of the imports from the closest producers. Of the 5 MBOD produced domestically, about 20% comes from offshore oil in the Gulf.

LNG is a blend of natural gas that can be liquefied at moderate pressure. It does not require a super stout vessel for containment. Domestic gas, supplied by natural gas utilities tapping into the pipeline streams, is predominantly methane with a few percent of ethane and propane; it can only be liquified at cryogenic temperatures, or it can be compressed and held in stout vessels. Anyone familiar with oxygen systems may be aware of the ability to store liquid oxygen in a cryogenic container at nominal temperature. There are efforts being made to ship liquified methane from gas wells to existng pipelines, in cryogenic trailers, built like the liquid oxygen, nitrogen and hydrogen tankers, as opposed to building new gathering pipelines to the nearest major pipeline.

Upshot here is that cryogenic storage of liquid methane may be a practical solution for fueling a fleet of natural gas driven vehicles. I might add that methane from coal, with basically no ethane or larger molecules, could also be tapped as a source for liquid methane.