The Myth That Using Nitrogen Increases Fuel Economy

Using nitrogen as a way to save gas seems to be gaining some popularity. It is used as an alternative to air in filling tires . The simple fact that retailers such as Costco are now offering nitrogen for your tires certainly suggests that the notion is becoming more mainstream. Air is free. Nitrogen costs almost $10 per tire at many retailers. Is nitrogen worth the extra expense? Here are some answers.

Let's start with a basic principle. Inhale...., now let it out. The breath you just took was 78% nitrogen. Of course you could tell that when you took that breath, couldn't you. That is the biggest problem with the assertion that nitrogen is better than air. 78% of the air is already nitrogen!

The basic claim made by nitrogen supporters is that nitrogen will permeate through the tire slower than oxygen because it is a larger molecule. By slowing the pressure loss of the tire, nitrogen will allow your tires to maintain the proper pressure longer.

The natural laws of physics don't support that contention. The rate of seepage of a gas through a porous membrane depends on it's mass and on it's size. Nitrogen and oxygen are almost the same size and nitrogen is slightly lighter than oxygen. If either gas is going to seep through the tire then the nitrogen would actually seep slightly faster than the oxygen.

Applying some common logic to this can illustrate why the nitrogen supposition is false. If oxygen did escape through a tire at higher rates than nitrogen, then as the oxygen escaped, the tire would be left with mostly nitrogen. Assuming this is what happens, then over time as oxygen has been lost there might be 91% nitrogen on the residual air in the tire instead of the original 78%.

Now in order to bring your tire back to the proper pressure, you top off your tires with a small amount of air. You have in effect added a small amount of air which is 78% nitrogen to the residual air in the tire which is 91% nitrogen. The end result is your tire is now filled with an air mixture with a very high concentration of nitrogen.

Continuing this scenario, as it is claimed, the oxygen continues to dissipate from the tire and the nitrogen remains behind. Now you have an even higher amount of nitrogen in your tire. Maybe 95%. As you repeat this process again and again your tire would eventually end up being full of only nitrogen.

The question is, if eventually you would end up with nitrogen filled tires by just repeatedly filling them with air, why would you fill them with nitrogen to begin with and spend the more money? It just doesn't make sense.

This is just a plain logical example as to how false the nitrogen claims are. There of course are a myriad of specific scientific answers showing why the nitrogen claims are based on myths and not scientific facts. Each one would require a separate article in itself to explain. In the end it seems you are seeing the single law of behavior that seems to play itself over and over.

Once again there are those who are taking advantage of a situation to make a buck. Who finds an advantage to filling tires up with nitrogen? Those selling the equipment and those retailing the nitrogen. They earn more profits. Who gets the short end of the stick? That' right, it's the consumer.

Article Source: http://www.articles.ask-me-about.com

Scott Siegel is the author of a 143 page manual of industry insider secrets on saving gas and money at the pump (beatthegaspump.com). Visit us to learn how you can get better gas mileage. Find out how to increase gas mileage.
This article is available as a unique content article with free reprint rights.