18 May 2008

This is how you turn a simple post into a nerdy post

Oh, here's where I left that blog. Awesome.

Ever since I linked this thing to Facebook, writing on here has lost its appeal. So that's out.

A list of things that are in:

1. Not Boston
2. Nuclear physics experiments
3. Rattle-can paint jobs on bicycle frames
4. Getting married in August and honeymooning in Belize
5. The picture in the latest SI of a shirtless Bob Uecker standing poolside and doing the play-by-play of Brewers' ping pong matches during their latest roadtrip
6. Beth's lemon bars
7. Jumping rope until your heart blows out of your chest ... you know, for kids
9. I swear that I don't read and write posts on Cleveland Browns message boards.
10. Wasting money on baseball cards

I typically get around on my bike, which, if you convert calories to gasoline, gets 3000 mpg. I got that from an article in the latest Bicycling magazine. To fact check that, one gallon of gas has 31,549 food calories, if you burn the gas under ideal conditions. So that means the writer estimates that you burn 10.5 Calories per mile on a bicycle. The wiki page on bicycle performance claims you burn 0.4 Calories/second over 15 seconds to accelerate to 25 mph and then burn 0.3 Calories/second to travel at an average speed of 25 mph. This means that the wiki page thinks you burn about 47 Calories per mile of bicycle riding instead, giving you a fuel efficiency of 675 mpg. Perhaps then the Bicycling magazine writer used a more modest estimate for a rider's average speed, maybe like 15 mph.

No one ever travels 3000 miles on bike in a single day, and you could probably achieve 675 miles over a week. So let's think about this in more real terms. An ABC poll in 2005 said that the average one-way commute distance to work is 16 miles. At almost $4 a gallon for gasoline and assuming a fuel efficiency of around 27 mpg, that would mean that the average commute to work today would cost roughly $2.40, probably more if you have to sit in traffic. Neglecting that this long of a bike ride would leave you a sweaty mess, at the going-all-out speed of 25 mph, you would burn 750 Calories. But at the calm pace that Bicycling magazine suggests, you would only require about 170 Calories. The tricky part now is estimating the cost of food. I don't know why anyone who would bike to work would also eat unhealthy food, but the average cost of high caloric junk food is $1.76/1000 Calories, meaning that depending on your pace, your one-way commute would cost between $.30 - $1.32. But everyone knows that people who are health conscious and ride bikes eat low calorie, nutritious food. At the study claimed astronomical price of $18.16/1000 Calories (which, by my experience actually sounds reasonable) then, your one-way commute jumps to a price that ranges from $3.08 - $13.62.

So, there you have it, I guess. In fuel consumption terms only, riding a bike can be more expensive than driving a car. Furthermore, since the cost of food and gasoline are fairly heavily correlated, no matter how high the price of gas becomes, riding may never be cheaper than driving. But, I would have to guess that riding a bike everyday and eating right makes you a better, healthier person. And there must be some value in that.

I was really surprised to find that in reality, the "3000 mpg" statement is completely misleading. When I first read that in the magazine, I thought to myself, "Wow, what a savings that will translate into!" (when I think to myself, I frequently speak like I'm selling a product) But alas, things are never so cut and dry.

ADDENDUM
My bicycle research colleague Matt, pointed out that on occasion, we'll buy this ridiculous mass-gainer product in a bottle as a post-workout supplement. We've always viewed buying these as an extravagant 1000 Calorie convenience since they cost roughly $4/bottle at the rec center here. In reality though, accepting the claim that the price of quality whole foods is very high, we were actually making an economic choice.

Of course, you should use this product as a dietary supplement, and if you drank a whole bottle before hopping on a bike, you'd have the worst stomach ache ever. But, in the scenario where you wake up in the morning before work, maybe eat something light to get the metabolism going, hop on the bike, ride 16 miles at a moderate pace (at the extreme pace of 25 mph, you would burn $3 on this trip), and then drink this product or one of their non-mass gaining alternatives to replenish your body then you would finally realize fuel savings with the health benefits that riding has to offer.

2 comments:

AtomicBagels said...

Button, you neglected a cost/benefit. Many people, particularly those who are inclined to bike, choose to workout. If this is indeed the case, then working out (and its effect on your body) is a benefit, and worth money. So even if it's costing them, let's say, $.50 per mile (which I still contend is high, but I need the wrapper from ground turkey to argue that), perhaps it is worth $.20 to the same person to get in a mile of biking. So the total cost may be somewhat less per commute, and for some crazy people, may be considered a benefit (positive net gain, of course). Also consider the time savings of this person. They would go to the gym later to get a similar workout, but now they got such a workout DURING their commute... I can't begin to guess an accurate estimate for saving someone a trip to the gym (or maybe it only saves 40 minutes of gym time, as they may still go, but will need to do less work), or maybe it just saves 30 minutes on the Ab Lounge. In further addition, the long term health benefits have to be totalled, including the number of days longer an avid cyclist will live. I think about the only thing you can't have on a bike that you can have in a car is A/C, and that is a cost of riding a bike, but it also costs a little extra gas while in the car. If you have a good idea on how to quantify some of these costs/benefits, I would be interested to know. All I can conclude is that I'm pretty sure, with all things considered, that cycling a commute is cheaper than driving it.

Sorry for the lateness of this comment.

physics & co. said...

I would bet that it is as well, especially since over the lifetime of a car, the price of fuel does not account for the majority of the car's total cost.

I think an interesting thing to look at is the percentage of money spent on food in order to maintain an average American's standard of living, and then look how that would change in order to accommodate a major lifestyle change such as beginning to cycle a daily commute.

The rising price of fuel has been so dramatic as to give the perception of a serious decrease in the standard of living. For example, the average American spent 26% more on fuel in 2005 than in 2004. Whereas the average American only spent 2.6% more on food over the same period (interestingly enough, Americans spent less on eating at home by 1.5% and more on eating out by 8.2%.

Pardon the puns, but this would all seem to motivate a popular perception that Americans will be able to stomach an increase in spending on food if it will help to defray the amount spent to drive their cars. And yet, that line of logic fails to follow reason when at the end of the day, all you've managed to do is to spend more.

People should be encouraged to cycle more, but I don't think that the activity is the shelter from inflation that some may try to portray it as.

The government document that I took the numbers from is actually pretty interesting: http://www.bls.gov/cex/csxann05.pdf