Sunday, October 29, 2006

Bicycles, Energy Cycles, Life Cycles

I was startled by a comment by Eleutheros, that if you walked everywhere you went, for your whole life, you would still not use as much energy as it takes to make a bicycle.

I got wondering whether this would be true when the energy of walking comes from a conventional Canadian diet, with far more calories used to produce a plate of food than the body gets out of it.

I went looking for a measurement of energy used in bike manufacturing, and came across an intriguing article(pdf) about energy use associated with electric bikes. It didn't answer my question about energy in manufacturing, since it focussed on differences between the electric bike and the human-powered bike, but it clearly illustrated the problem I was wondering about.
Despite the intuitive sense that electric bikes would require more resources than regular bikes, life-cycle analysis shows that they actually consume 2-4 times less primary energy than human riders eating a conventional diet. This conclusion is largely due to the considerable amount of transportation and processing energy that is associated with our western food system.
When the analysis considered a cyclist eating local food, and electricity coming from hydro-power, the electric bike and the human-powered bike were about on par.

It's a sad commentary on our society, when you are better off letting a coal-fired plant push your bicycle than eating the food you need to spin those pedals yourself. Yet when you look at lists of "things you can do to conserve energy," how often do you see the suggestion that you plant a garden?

7 comments:

Anonymous said...

There are a number of these apparent contradictions that dismay.

The cost of recycling rather than simply dumping into a landfill and making a fresh new replacement from new sources. I think we're getting better at counting in all the tangible and intangible costs of, for example NOT recycling. There are real social and environmental costs associated with, say, the landfills needed if we don't recycle, and surely those should be deducted from the cost of recycling.

Or considering the more appropriate comparison between bicycling and driving, rather than bicycling and walking. The consideration of bicycling isn't limited simply to the cost of the energy and raw materials to produce the bicycle. Other benefits not enjoyed by walking cut in too: what about the extension of distance and speed that bicycling offers, and the commensurate reduction in time of transit?

Or the transportation costs of purchased rather than locally grown food. I'm glad to see that that's being automatically included in calculations, now, but admit I haven't seen much push toward planting a garden except by local grassroots enthusiasts.

arcolaura said...

Wayne - I Googled "what you can do conserve energy" and got lots of lists, but it was about six lists down before I found one that mentioned planting a garden, and that was buried in a section titled "Go organic." And you're right, it was more of a grassroots website. The corporate sites were all pretty much parroting each other about replacing light bulbs and installing setback thermostats - and many were direct cut-and-pastes, as if there is no creative thinking left to do.

Madcap said...

Morning, Laura. I'm poking my nose out of my burrow.

I can't quite figure the resistance to food gardening. I know quite a few people who get downright hostile when you suggest that if they're concerned about their budget, or their planet, they should plant a vegetable garden. It's like you're threatening a right to cheap-n-easy groceries off the shelf.

Bikes may not be nearly as efficient as walking, but they're still a heckuva good thing.

arcolaura said...

Morning, Madcap! Good to see you out and about again.

I'm all for biking - although I prefer to give it up once the snow comes. I had an adventure yesterday, biking up the snowy icy streets to fetch the car from Garth's workplace on the far side of town, after realizing that the key to my truck was in his pocket in the next town over - where Ruth needed to be, for her band rehearsal. If we weren't wrapped up in all these scheduled and centralized activities, we could adjust to this weather and just walk (or stay home and have a kitchen party!).

I wonder if the resistance to food gardening is actually a resistance to the whole business of having to think about where your food comes from. When you face the amount of work it takes, the little food you get for each square foot and hour, the vagaries of results, the competition from critters - all this is bound to stir up discomfort about the luxurious abundance in the grocery store. Perhaps it stirs a shadow of that ancient guilt about something having to die, in order that we may eat and live.

Anonymous said...

Biking is fun (at least most of the time, perhaps not in icy subzero weather, but then neither is walking). There's really nothing closer for us bipedal, wingless humans to flying than coasting down a hill on a bike.

Let's try to put a monetary value on that. We can't, but we should.

I suppose esthetics fits into the contemptible realm of mental health and optimism, that category that motivates so much more that actually can be tabulated in monetary terms, but is scorned as unworthy of contribution to an economy. What a sad commentary.

arcolaura said...

I have that uneasy feeling that a misunderstanding just turned into an argument between people who don't even disagree, really.

Coasting down hills is a rare treat around here. I love to "fly" down Perry's Hill toward the creek, with that extra thrill of fear that some monstrous truck might overtake me before I get beyond the steep-banked part and get slowed down enough that I can hit the ditch safely.

Coasting down the big hill from the farm was always too scary to be fun, keeping to the narrow hard-packed wheel tracks and holding on the brakes in case I needed to swerve into the gravel.

Anyway, biking out to Perry's Hill takes a bit of time, and I didn't do it much this year. I think that was partly because I was busier with the garden, trying to reduce our dependence on Californian and South American and South African food, and thus reduce my biking footprint (wink). But partly I suspect I am biking less because I'm doing so much tail-chasing philosophizing here, I'm getting dizzy.

As an attempt at a reply, Wayne: we bought both kids bigger bikes this year, and I don't regret it.

And I'm taking a belly-dancing class, which involves more cash diverted from the homestead dream and more food consumption (I always come home hungry), but it's exactly what my sluggish body needed and the aesthetics are sumptuous. So I don't regret that either.

But I still think it's worthwhile to look at our cherished "green" activities from different angles, and see if we can learn something. Not that anyone should give up biking, but maybe we shouldn't feel too smug about biking to the store to buy food that came from the other side of the planet. And maybe we should think twice about buying a newer and better bike. The popular ideas and suggestions of things to do for the environment are not a very good guide if you want to make some serious lifestyle choices for maximum benefit.

Hmmm. Just re-read things, and got thinking about the immeasurable benefit of biking as a substitute for, say, driving to the lake and going water-skiing behind a powerboat. Besides the enormous fuel saving, there's the appreciation of the landscape seen at a slower pace; there's the quiet; there's the staying home, so the community has people in it on the weekend, so the grocery store and the belly-dance teacher and the movie theatre stay in business...

Oh, and by the way, can anybody tell me the meaning of the song "Spinning Wheel" by Blood, Sweat and Tears?

Elmo said...

I can agree with your logic about burning calories, however, there are some people, like myself, that have arthritis problems and still like to ride a bicycle. It is not that we are lazy, but the last time I went riding I had to make it up a pretty steep hill and my joints were really sore the next day. Thank God they are building more electric bikes and electric mopeds for we older folks that want to stay active but also have to watch our joints!

God Bless
ELMO