Do Morning Fill-Ups Save On Gas
Some people say it’s better to buy your gasoline first thing in the morning, rather than in the heat of the day. That’s because gasoline, like all liquids, expands when heated. The basic facts are correct, but the advice is not. 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% while the energy content remains the same.
Filling stations typically store their gasoline in underground tanks, where the temperature variation during the day is much less than in the air above. The result is that the temperature of the gasoline coming out of the fuel nozzle varies very little, if at all, during any 24-hour stretch at any particular station.
A 15-degree difference, for example, would result in a one-percent gain in volume. Or, just a few cents difference on the first gallons pumped — not enough to change your schedule or routine in chasing costs, especially if it might increase your fuel consumption in the pursuit.
