Hot fuel for you and cold cash for big oil When gasoline gets hot, it expands. But U.S. fuel pumps don’t account for the bigger volume, and it’s costing American consumers about $2.3 billion a year.
It works this way.
As a liquid, gasoline expands and contracts depending on temperature. At the 60-degree standard, the 231-cubic-inch American gallon puts out a certain amount of energy. But that same amount of gas expands to more than 235 cubic inches at 90 degrees, even though consumers still only get 231 cubic inches at the pump.
Put simply, every degree over the 60-degree standard diminishes the energy a 231-cubic-inch gallon delivers to the nation’s fleet of cars, trucks, boats, buses and heavy equipment — and forces drivers to consume more and pay more for fuel.
It is basic physics that, depending on the temperature, can amount to just a few cents per gallon. But it adds up to big money — coming straight out of consumers’ pockets and going right to the bottom line of major oil companies and other fuel retailers in the energy pipeline.
Moreover, it’s perfectly legal, because even though your local filling station measures out your gas as if it were stored at 60 degrees, no law requires retailers to adjust the pump to reflect the expansion of hot fuel.
In other words, no law ensures you get what you pay for.
http://www.ooida.com/Documents/hot_fuel_part1.pdf