I just read a piece in my local newspaper with some interesting info. The article is supposed to be posted in a special section of this site: http://www.orangevalejournal.com — although at last check I couldn’t actually find the article on the site.
I’ll quote the salient portions of the article:
“These tips come from the Kinder Morgan Pipeline where [the source] works in San Jose, CA. They deliver about 4 million gallons through the pipeline in an average 24-hour period. One day they are pumping diesel; the next day is jet fuel, and gasoline, regular and premium grades. They have 34 storage tanks here in San Jose with a total capacity of 16,800,000 gallons.
And here are some of his tips.
1) Only buy or fill up your car or truck in the early morning when the ground temperature is coolest. 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, so buying in the afternoon or in the evening, your gallon is not exactly a gallon . . . A 1-degree rise in temperature is a big deal for this business. But service stations do not have temperature compensation at the pumps.
2) When you’re filling up, do not squeeze the trigger of the nozzle to the fastest mode. if you look, you will see that the trigger has three stages: low, middle, and high. in slow mode 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 of the liquid going into your tank becomes mixed with the vapor. Those vapors are being sucked up and back into the underground storage tank so you’re getting less worth for your money.
3) One of the most important tips is to fill up when your gas tank is HALF FULL or HALF EMPTY. The reason for this is, the more gas you have in your tank the less air occupying its empty space. Gasoline evaporates faster than you can 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 . . .
4) Another reminder, if there is a gasoline truck pumping into the storage tanks when you stop to buy gas, DO NOT fill up — most likely the gasoline is being stirred up as the gas is being delivered, and you might pick up some of the dirt that normally settles on the bottom. ”
I can’t say whether all the information is scientifically accurate or not, but some of these points echo advice I’ve heard elsewhere over the past several years, so I thought I’d do my best to pass it along to other folks. You can decide for yourself how valuable (and helpful) these suggestions actually are.