Chamblee54

This information was originally posted six years ago. PG received a chain letter email about gasoline prices, with these suggestions. With demand increasing, and supply decreasing, the price of petroleum is going to go up. Pictures today are from The Library of Congress.
Only buy or fill up your car or truck in the early morning when the ground temperature is still cold. Remember that all service stations have their storage tanks buried below ground. The colder the ground the more dense the gasoline. When it gets warmer gasoline expands. When you pump in the afternoon or in the evening… your gallon is not exactly a gallon. In the petroleum business, the specific gravity and the temperature of the gasoline plays an important role.
When you’re filling up do not squeeze the trigger of the nozzle to a fast mode. If you look you will see that the trigger has three (3) stages: low, middle, and high. You should be pumping on low speed, thereby minimizing the vapors that are created while you are pumping. All hoses at the pump have a vapor return. If you are pumping on the fast rate, some liquid that goes to your tank becomes vapor. Those vapors are being sucked up and back into the underground storage tank so you’re getting less fuel for your money.
Fill up when your gas tank is HALF FULL or HALF EMPTY. The more gas you have in your tank the less air is occupying the empty space. Gasoline evaporates faster than you might imagine. Gasoline storage tanks have an internal floating roof. This roof serves as zero clearance between the gas and the atmosphere, so it minimizes the evaporation.
If there is a gasoline truck pumping into the storage tanks when you stop , DO NOT fill up–most likely the gasoline is being stirred up as the gas is being delivered. You might pick up some of the dirt that normally settles on the bottom.