The economics of biking to work
Warning: this does not have the conclusion you might expect.
Until just recently my bike was the most expensive mode of transportation that I owned – and yes, that includes my car. Needless to say, I enjoy being physically active and I particularly enjoy biking.
So when I first moved to Phoenix I jumped at the opportunity to take full advantage of the roads and the spectacular weather. I began biking to and from work - 15 miles each way - three days a week. It was a win-win: I incorporated my commute into my daily exercise and I saved money on gas. Or so I thought…
On one particular afternoon, as I sat at my couch scarfing down food after my bike ride home, a question popped into my head: “I wonder how much more I eat on days when I bike to and from work?” and then, after a series of Holmesian-esque questions: “Do I even save money by biking to work, after accounting for all of this extra food?”
Shortly thereafter, I was hacking away on my calculator trying to find an answer. Here’s how it went…
Start with the money saved on gas. It’s a 17 mile drive each way. Assuming an average fuel economy of 25 miles per gallon and an average cost of $3.50 a gallon, that works out to $4.76 in gas per day I drive to work and therefore $4.76 in savings per day I bike.
Most people would leave it at that, but I’m not most people. Using my average power output and travel time (did I mention I’m a data nerd?) and some fancy science, I calculated that on average I burn approximately 950 or so calories for the round trip bike ride.
Thanks to my fitness tracker I know my average calorie consumption per day. I also know how much money I spend on food thanks to my fervent use of Mint.com. (Side note: if you haven’t checked it out yet, I would highly recommend doing so; it’s a convenient, useful and incredibly powerful tool for tracking where your money goes.) It turns out that I spend about $1 for every 205 calories I eat.
By extension, I’m spending an extra $4.63 on food on the days I bike to work. That works out to a net savings of – drumroll please… $0.13 for my 30 miles of biking.
Wait, what? $0.13… that’s nothing! That’s literally a rounding error on my calculations, so what I’m saying is that I don’t save any money by biking to work.
At this point it’s worth mentioning some of the caveats of this analysis. First and foremost, if I drove to work every day I would still go on bike rides, so the analysis should really only apply to the exercise I do because of the commute in excess of what I would normally do. Second, I don’t account for the cost of wear and tear on my car. I also don’t account for the cost of wear and tear on my bike, often in the form of repairing flats. Finally, I don’t factor in the lower cost of my medical bills due to the improvement in my health from the added exercise.
Still, the point comes across loud and clear: I don’t save nearly as much money as I had originally thought when I bike to and from work. But true to my exercise-loving self, that won’t keep me from doing it.
