Habits & truth

Blog 4 – Habits and Truths.
For this blog we have to write about something we have been brought up as believing is true but in fact not be.

HABIT:
The habit I have chosen to blog about is about saving money by refuelling your car in the morning.
There are two theories to this.

1. Liquids expand as they get warmer.
Warm Petrol expands and cooler petrol is denser. So if you purchase petrol in the heat of the day you get a smaller volume of petrol.

2. As liquids warm evaporation increases.
Pumping petrol in the heat of the day causes the fuel to evaporate out of the open fuel cap causing a loss in petrol.


This myth has been in the family for years. I have questioned it but never done any research.


FACTS:
• "Gasoline does expand and contract a little depending on its temperature. When gasoline rises from 60 to 75 degrees F, for instance, it increases in volume by 1 percent while the energy content remains the same". (Hard, 2008)

• Tests were also conducted on the temperature changes on petrol stations underground fuel tanks throughout the day.
o" Results. While the air temperature between filling varied by up to 12 degrees, the fuel in our underground tank stayed at a steady 62 degrees F. As a result, we found that after the first few gallons were pumped, the fuel temperature coming out of the nozzle varied very little between morning and afternoon". (Hard, 2008)

• "Someone who gets up at dawn to fill up early won't save even one simple penny. And if he's racing to the gas station to beat out the other early birds, his fuel costs will be 35 percent higher than the guy who drives calmly, according to Edmunds testing. (Romans, 2008) People who really want to save money on gas should look to change their driving style instead of counting on the cool-fuel theory." (Reed, 2008)

CONCLUSION:
While the theory behind the myth is sound the practicality of the myth is false. The savings are Negligible and if you go out of your way to refuel in the morning you will be spending more on fuel then fuelling up later in the day when you are near a petrol station.


REFERENCES:
Hard, G., 2008. Consumer Reports. [Online]
Available at: http://news.consumerreports.org/cars/2008/08/gas-pump-myth.html
[Accessed 23 04 2013].
Reed, P., 2008. Edmunds. [Online]
Available at: http://www.edmunds.com/fuel-economy/three-gas-price-myths.html
[Accessed 23 4 2013].
Romans, B., 2008. Edmunds. [Online]
Available at: http://www.edmunds.com/fuel-economy/we-test-the-tips-part-ii.html
[Accessed 23 4 2013].