Friday, May 30, 2014

Actual savings: biking to work

The latest print edition of my Dollar Stretcher newsletter contains an article called "Reduce the Cost of Your Commute." (It isn't up yet on their website as I write this, but it might be by the time you read this.) It poses the question, "with the cost of gas hovering near $4 per gallon...how can you reduce the cost of commuting or make the time spent more profitable?" The article then lists a number of suggestions, such as changing your work schedule, carpooling, working from home, and the one that Brian favors, biking to work. Naturally I was pleased, not to say smug, to see part of our lifestyle endorsed in this way. But I couldn't help asking myself: does it really save all that much money? Over a year ago, I crunched the numbers on line-drying laundry—another money-saving measure that's widely touted in publications like The Dollar Stretcher—and found that the savings were actually pretty trivial. Last summer, I did a similar calculation for homemade laundry detergent and found that depending on how cheaply you can buy detergent, making your own may not in fact save you any money at all. Might biking to work be the same kind of thing—a feel-good activity that doesn't have much of a financial payoff?

Calculating the answer is pretty simple. I know that the distance Brian commutes to work is about four miles each way, and I know that our little Honda Fit gets about 40 miles to the gallon in typical mixed driving. (The EPA claims this car only gets 29 mpg in mixed driving, but I don't know what kind of idiot they've got driving it, because our mileage has never been anywhere near that low.) However, short trips, like Brian's daily commute, get lower gas mileage than most of the driving we do, so to be fair, let's assume that Brian only gets a measly 32 mpg out of the car while driving to work. That means that for every 8-mile round trip he makes, he uses a quarter of a gallon of gas. The receipt from our last gas fill-up shows that we paid $3.40 per gallon, which means that every day Brian rides his bike to work instead of driving, he saves 85 cents. So if he commutes by bike an average of three times a week, April through November (35 weeks), his pedal power saves us $89.25 per year. That's a lot better than the $14 or so I save hanging laundry, but it's not exactly a slam dunk.

Now, how do those savings work out on an hourly basis? Well, Brian's relatively short commute takes him about 25 minutes on the bike, while driving in rush hour traffic takes roughly 15 minutes. (On the bike, he can go by way of the park and skip a lot of the traffic.) So, for a round trip to and from work, he spends an extra 20 minutes to save that 85 cents, for an hourly rate of $2.55. That's only 30 percent of New Jersey's minimum wage, which doesn't look that impressive.

However, biking to work has additional benefits beyond saving money. The Dollar Stretcher article points out two of them: "you'll save dollars and get a workout at the same time," and "Peddling [sic] past cars stuck in rush hour traffic will make the ride so much more pleasant!" Both of these have definitely been the case for Brian. Since he started biking to work on a regular basis, he's dropped a size in pants, and his blood pressure is much improved. And while on a typical day, biking to work takes longer than driving, there are also the occasional atypical days—usually days when a football game at Rutgers has brought traffic to a near-standstill—that he's able to get home on his bike much, much faster than he could have in the car.

Then there are the environmental benefits. If Brian bikes to work 105 times each year, then over the course of the year, he saves 26.25 gallons of gas. According to this formula from the EPA, the carbon output of that amount of gas is 0.23 metric tons, or about 2.5 percent of our total carbon footprint. Not a huge environmental benefit, perhaps, but certainly a measurable one. (Actually, when you do the math over the course of a whole year, even my line-drying efforts start to add up; drying 60 loads of laundry every year saves us about 0.3 metric tons of CO2, which isn't bad at all.)

Now, your mileage, as they say, may vary—and so may the length of your commute and the amount you pay for gas. If your car is a lot more efficient than ours, or your commute is a lot shorter, than biking to work may save you less than it does us; on the other hand, if your car is a lot less efficient, or the price of gas in your state is much higher, then you might save a lot more than we do. It's pretty easy to crunch the numbers for yourself and figure it out: just take the number of miles in your daily commute, divide by your car's mpg, and multiply by the cost of a gallon of gas. But even if the number you get as a result seems low, that doesn't necessarily mean that biking to work isn't worth your while. Like hanging laundry, it may turn out to be worth it for the exercise and fresh air alone.

6 comments:

CTMOM said...

I found your comment regarding line drying laundry to be interesting. In CT, we have very high electric rates, and they are set to go up 8%-thanks. : (

that said, I have done the maths on line drying, and calculated that I save 90 cents each time I line dry a load. On average, I do at least 8 loads/week, so rounding this up, call it $8/week or $416/year. I'll keep line drying-I am saving wear/tear on the actual laundry, the environment and my electric bill.

Amy Livingston said...

Yep, that's another case of "your mileage may vary." My savings from line-drying worked out to only 24 cents a load, mostly because we have a gas-powered dryer rather than an electric one. And we do between one and two loads a week, so the yearly savings are pretty small. But I do it anyway, because basically, I enjoy it.

Adam Lang said...

Surprised you didn't factor in wear and tear on your car. I normally just use the IRS mileage guidelines for costing out trips, maybe modified a bit by fuel economy of the car, to calculate savings from not driving.

If you're lucky enough to live in a state with pay-per-mile car insurance, that would also factor into it.

For me it's a much more straightforward calculation: for every day I jog to work, I save $2 in bus fare. For every day I walk home, I save $2 in bus fare.

Amy Livingston said...

I was going to mention the wear and tear factor, but I couldn't fit it neatly into the discussion. Basically, while biking to work saves some wear and tear on the car, it also puts some wear and tear on the bike, so rather than try to calculate both of these, I just assumed they canceled each other out.

For you the calculation is much easier, since jogging doesn't involve any equipment. (Well, there's presumably some wear and tear on your knees, but I don't know how you'd put a dollar value on it.)

Reminds me of the old joke: "Hey, honey, today I ran all the way home behind the bus and saved two dollars!" "Well, why didn't you run behind a taxi and save ten?"

Adam Lang said...

I suspect that the cost of wear and tear on a bike is quite a lot less than that on a car. Especially since, though brakes and tires do wear out, I've had the same bike frame since I was 16 years old.

As for jogging, now I come to think about it, it does cost me a fair bit: a new pair of shoes every 4 months means $25 a month or so. (Alas, there's no such thing as an inexpensive pair of 11AA shoes.) But that prevents said wear and tear on my knees.

Amy Livingston said...

Yeah, well, in our case maintenance costs on the bike include the cost of having one really nice bike stolen (grumble, grumble) and replacing it with a cheap secondhand bike...and a very good lock that cost more than the bike.