Environmental heresy (#1 of 2): is bicycling best?

[fubar72]

Here's some food for thought:

Recently, I rode my bicycle 15mi to my old neighborhood. I wanted to work out at my old gym, but needed "fuel" to do so effectively. A few slices of pizza, drink, and $4 poorer, I grumbled to myself that--even with the high cost of gas--cycling was a money-loser.

That made me consider: it's reasonable to assume that the cost of an energy source (food is energy, after all) has a bearing on the amt. of energy used to produce it. The most efficient use of food as fuel in the US is ethanol (biodiesel is from a waste product, and thus not wholly applicable), which consumes 60-80% of the energy contained just to make it! (That's on an industrial scale...I'm sure it takes more energy to put a bottle of booze in my hand than the liquor contains.)

Now, consider the "equivalent MPG" of the bicycle. It took me 1hr to bike 15 mi, during which time I estimate I burned 900kcal (dietary Calories). A gallon of gas has roughly 31,000kcal, so (if I could drink gasoline) I'd get 515 MPG on my bike, roughly 17X better than my car and 8X better than my motorcycle.

However, a LOT of energy is used growing, transporting, selling to the restaraunt, and cooking and re-selling in an air-conditioned dining room. How much more? Dunno, but if it's 8X more (and I can see where it could be) it becomes a moot point, energy-wise, if I motorcycle or drive!

Obviously, if I consume in, I can choose foods that make it ecologically advantageous, but if I will need to eat out at my destination, it'll ALWAYS be more expensive to bicycle, and possibly just as energy-consuming!

I'd appreciate comments, either yea or nay.

[crankyelbow]

You'll need to eat whether you drive or bike.

Energy used is not the concern.... its energy used naturally or un-naturally.

Your serving the earth by eating and, well, living. Your not serving the earth by converting our air into a cancerous problem.

That said... daily life in america *must* lead to pollution in some way, its inescapable. A good time to re-evaluate our lifestyles, but we are all tied up within a system that does not allow for such a simple escape.

[zz_blackjack]

"You'll need to eat whether you drive or bike."

I was just about to say that myself...

I want to throw another wrench into the mess, though... what about what it costs you in the extra time that it takes to ride a bike versus driving. It doesn't necessarily have any effect on the environment, but it does cost you.

[drumminmama]

theoretically you could work less not having to pay up keep and insurance on a car, let alone a car payment.
there's probably a tipping point there.

[fubar72]

Here's an interesting website i found: http://www.lafn.org/~dave/trans/ener...energy.html#s2

The fossil fuel energy required to travel on a typical bicycle is compared to that of a typical automobile. Based on the mechanical energy used (by calculating the forces needed for steady motion) the bicycle is roughly 10 times more efficient. But since the auto must brake from a higher velocity it uses relatively more braking energy than a bicycle so the ratio of 10 becomes about 13.5. But while an auto engine is rated about 50% higher in thermal efficiency than the "human engine", in actual urban use the auto engine is about 40% lower in thermal efficiency and about 10% of fuel is burned during idling. Result: The bicycle is about 25 times more efficient than the bicycle. But when one considers that for every Calorie of food eaten, it takes perhaps 15 Calories of fuel to grow, transport, and cook that food, then the bicycle is only about 2/3 more energy efficient than the auto. But if one counts the energy cost of the extra time it takes to travel by bicycle, it's not clear that the bicycle is any more energy-efficient than the auto. But if one counts the energy expended bicycling as the energy cost of healthy exercise and doesn't count it as an input to transportation, then the bicycle is very energy-efficient.

I guess my point in posting this was to get people to think critically about environmentalism: its seems that environmentalism is often practiced as an ideology rather than by using critical though processes and scientific rigor. It seems that, given the right circumstances, a high-MPG motorized alternative ultimately can consume less energy. Also, in the example I gave, I probably saved energy vs. driving because, had I driven, I'd probably have wanted to do cardio (ironically on an exercise bike?) that would have burned calories with nothing to show for it. (But that's more about "two brids w/ one stone" than the inherent efficiency of the bicycle.)

I mean, I bicycle because it's just more fun that driving a car; I don't feel the need to get all sanctimonious about it!

[mamaKCita]

after all, you could have worked out at a LOCAL gym...OR at no gym at all.

[The Scribe]

I have read that riding a bicycle is the most efficient means of converting calories into motion. By riding a bicycle you consume fewer calories than an animal moving as qucikly. You consume far fewer calories than you do driving a car. The caloric cost of moving and cooking the food should be compared with the comparable costs of moving and refining the petroleum.

[mamaKCita]

btw, i was being pithy. i live in a town where bicycles and youth driven environmentalism is simply a part of life. i love that. but every now and then you get someone being a bit unreasonable who expects you to live your ENTIRE existance locally. i'm all for the farmer's markets and easy access activities and stuff. it's great. but sometimes the call of a favorite past place comes to you and you just have to go. yeah, thos people are pretty rare, but still, they grate on my nerves a bit.

[hacker.pizza]

2 people actually said that you have to eat no matter what. Imagine that. When you use more calories you need to consume more calories. Simple as that. When you work out in the sun you get a craving for salty foods. You've lost salt in sweat and need to replace it. Same deal.

Now you didn't even add in the fact that you will be exhaling more CO2 than usual, adding to the dangers of the coming Ice Age, Global Warming, Climate Change, or whatever other control-based propaganda campaign is popular at the time.

As far as excersize goes, most people, as far as I know, don't need to go to the gym anyway. That seems like a pretty ignorant excuse. I won't be going to the gym whether I ride a bike or not.

Originally Posted by The Scribe

The caloric cost of moving and cooking the food should be compared with the comparable costs of moving and refining the petroleum.

Why? That's already accounted for at the pump, silly.

[Eugene]

you could get a bike with an electric motor, they're becoming increasingly popular where i live.
come winter time, however, and you need a car in this city.

neways, you could just ride your bike instead of going to the gym, and thus make the whole point moot.