I sat paralyzed (not literally) at the intersection.
Just a few moments before, I pulled up my Gas Buddy app ( a free App I highly recommend) and found out what I always found out – that Sam’s Club had the cheapest gas in town. The Sam’s was 1.5 miles in the wrong direction. The gas gauge was on empty.
The closest gas station that I’d be passing had gas for $3.25 per gallon, but it was $3.20 at Sam’s.
What should I do? Is it worth driving out of the way for cheap gas?
In the end, I decided to do what any logical person would do: don’t get any gas, and be sure to rush home and write a post about how to calculate how far out of your way you should drive to get cheap gas.
My trial becomes your convenience.
Is it Worth Driving Out of the Way for Cheap Gas?
You’ll need a few bits of information before you possibly begin to logically answer this question.
1. How many miles per gallon do you get in your vehicle? When we were in PNG, we kept a gas log so we could know our miles per gallon. It’s a simple thing to do. Write the odometer reading when you get gas, and the next time you get gas write your odometer reading and the number of gallons you added. The difference in the odometer reader is the distance you’ve traveled on the number of gallons you added. Let’s say you’ve travelled 150 miles, and you put 5 gallons in your tank. Take 150/5, and you’ll find out that you’re getting 30 miles per gallon. Personally, I wish that was the case for our illustrious PT Cruiser. This gas sucking car gets us about 17.5 miles per gallon in town.
Remember: Be sure you know how many miles per gallon you get around town as your town driving will probably be more reflective of your driving to a gas station.
Tip: As an alternative to keeping a paper record, if you have a smart phone you could get an App like Gas Cubby (free).
2. Where is the cheapest price of gas and how far away is it? What is the price of gas at the closest gas station?
If you don’t have a Gas Buddy App on your phone, you can always visit gasbuddy.com on your home computer. When you do this, you’ll be able to find out how far away it is for the cheapest gas, and you’ll know how much it is at the closest location.
3. How much gas do you need? Do you know your fuel tank size? When it’s on empty, how many gallons or liters does it take to fill? How full or empty (depending on your life outlook) is your gas tank?
The Math Formula: Is it Worth Driving Out of the Way?
Distance you need to drive: In my example above, 3 miles out of the way.
Cost to drive that distance: At 17.5 miles per gallon and $3.25 per gallon (what I paid the time before), I’d pay .1857 per mile. (price per gallon / miles per gallon; in my case 3.25/17.5). Now that I know how much it takes in gas to drive a mile, I multiply that by the number of extra miles I’d need to drive to get to the cheaper gas station. Thus it would cost me 56 cents (.1857*3) to drive 3 miles out o the way for the closest gas station.
Distance to gas station * cost per mile = how much it costs to get to the gas station
My tank is a 13 gallon tank, and my gas light just came on, so I probably needed about 11 gallons (the light comes on when I have two gallons left). Since Sam’s was .05 cents per gallon cheaper, I’d save .55 cents there.
Savings per gallon * total number of gallons needed = total amount you could save
It would not be worth driving 3 miles total to save 5 cents per gallon because it would cost me more in gas than I would save. Even if I could save more by driving to the gas station, I still haven’t factored in the time involved and other costs like oil cost and wear and tear on the vehicle.
Is this a waste of time?
Possibly, but likely not.
I’ve done this once, so I know how much I can use as a general rule for cost per mile. From now on, I can do the math easily in my head.
It’s taken me about 20 minutes to come up with this post and work out this little math formula. If I could save $1 every time I get gas because I make savvy spending decisions, then I could save at least $50 this year. That’s like getting $150 an hour. It’s worth it in my book.
The best part is this helps me decide when I should run to a second grocery store because they have a sale. Does the cost in gas justify the extra savings? This helps when considering making an extra trip to do something. Does the cost in gas justify doing this today, or should I just do it next time I’m out and about?
Remember, if you drive a lot or have a massive vehicle that holds dozens of gallons, you’re savings can add up even more quickly.
Do you ever drive out of the way to get gas? Have you ever figured out your cost per mile? Do you think this whole exercise was a complete waste of your time?