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What's the Carbon Footprint of Bicycling?
Hugh Pickens writes "Brian Palmer writes that although none of the major manufacturers has released data on their energy consumption and how much greenhouse gas making a bicycle requires, Shreya Dave, a graduate student at MIT, recently estimated that manufacturing an average bicycle results in the emission of approximately 530 pounds of greenhouse gases. Therefore, given a 'typical U.S. diet,' you would have to ride your bike instead of driving for around 400 miles to cover the bike's initial carbon footprint. However, calculating the total environmental impact of a mode of transit involves more than just the easy-to-measure metrics like mileage per gallon. Using a life-cycle assessment, Dave concluded that an ordinary sedan's carbon footprint is more than 10 times greater than a conventional bicycle's (PDF) on a mile-for-mile basis, assuming each survives 15 years and you ride the bike 2,000 miles per year. What about other ways to get to work? According to Dave's life-cycle analysis, the only vehicle that comes close to a bicycle is the peak-hour bus — and it's not really that close. A fully loaded bus is responsible for 2.6 times the carbon emissions total of a bicycle per passenger mile while off-peak buses account for more than 20 times as many greenhouse gases as a bicycle. What about the carbon footprint of walking? 'Walking is not zero emission because we need food energy to move ourselves from place to place,' says environmentalist Chris Goodall. 'Food production creates carbon emissions.'"
The whole carbon footprint thing is overrated. and the carbon credits is just a way to make businesses feel better about wasting and polluting. What's the carbon footprint of sleeping? What's the carbon footprint of sitting on the couch watching TV? What's the carbon footprint of eating a microwave pizza? What's the carbon footprint of teleporting? geez
Let's see, walking is not zero carbon because of the food energy.
After the carbon cost of making the bike, biking's not zero carbon either, for the same reason.
But I only ride my bike for exercise, thus I don't save anything vis-a-vis my commute to work, and I have the food energy cost. Therefore my bike riding definitely has a carbon footprint.
Oh noes. Guess I better stop riding and turn into an obese blob for the sake of the environment.
...it is still going to save the rider in gas money (provided they're riding the thing whenever they can, obviously a bike rotting in a garage does no one any good).
I see a lot of people screaming left and right about how all these technologies like mass transit and solar power and such are "just as bad", but the end result is always the assertion that "we should just do whatever because nothing we do will ever help so screw it". Here in Madison, WI, where there are a fair number of cyclists, there are still those people that go out of their way to prevent them from riding. Every article about a bike riding event warrants thousands of comments about how much these people wish they could go drive over the riders in their Canyonero and other such crap.
Every little bit helps, does it not? And why so much hostility for green energy initiatives? Are we just going to keep on burning oil and coal for power? I mean, clearly we need to start coming up with alternatives, right?
The manufacturing process of the bicycle will have roughly the carbon footprint of manufacturing a car door. And these researchers want us to think you have to put 400 miles on the bike before break-even?
I'm sorry, but if they can make such an obvious biased mistrake, why should anybody give even a moment's thought to the rest of their study?
Cheers,
b&
All but God can prove this sentence true.
Like pedestrians . . . (cue snare drum rim shot).
Have you ever tried to cross Randall at Dayton on foot? With the walk sign on? With some fine upstanding citizen on a 15-speed bombing through the red light? Or at that marked crosswalk across University near where Bob's Copy Shop in University used to be? When that walk sign is on, I guess the red light for the cross traffic doesn't apply to cyclists in the bike lane.
Of course, as a pedestrian, you are never of any danger of being hit, with the force of an NFL free safety making a flying tackle, only taking the hit, on cement, without helmet or pads, because the cyclists know how to weave around any pedestrian who dares to enter a crosswalk.
Seriously and all snark aside, I would have a lot more sympathy for the concerns of cyclists if there was a little more respect for people on foot. Is that so anti-green?
Yeah, that's a tricky aspect of public-transit accounting. In particular, you can't decouple every bus from every other bus, because choices to use the system depend in large part on the overall system. If you cut all past-9pm buses, you might save a bunch of money and carbon emissions looking just at those buses, but you might also depress ridership on the daytime buses, because suddenly people are worried that they'll get stranded at work if something comes up and they have to stay late, so better play it safe and drive.
To properly account for what, say, the 10pm-midnight buses are doing, you need a more systemic analysis that predicts what would happen to the usage of various modes of transit, including at other times of the day, if those buses were decreased/increased/cancelled/kept-the-same.
This is also a common problem with spacing: it's tempting to think, we have N passengers an hour and run a bus every 10 minutes, but N/2 totally fit in a bus, so we could really improve our finances if we just ran a bus every 30 minutes instead. But when the bus runs every 30 minutes rather than 10 minutes, a lot fewer people take it.
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Even worse, don't forget that it takes ten pounds of crude oil to deliver a pound of food to a plate, when everything is added together.
Look, you need to be careful when you use statistics from sources that don't spell out exactly how the figure is generated. A quick google http://wiki.answers.com/Q/How_much_does_one_gallon_of_crude_oil_weigh search of how much oil weighs per gallon comes up with about 7 pounds per gallon for light sweet crude. Now, today's oil price for West Texas Intermediate is $85 per barrel http://www.oil-price.net/. There are 42 gallons per barrel so the cost per pound is
42 gallons * 7 pounds per gallon = 294 pounds for a barrel
$85 / 294 pounds = .29 cents per pound
So according to your statement above, food requires 10 pounds of oil per pound of food, SO the average pound of food should cost at least $2.90 because that is how much it would take to cover just the cost of oil. It ignores cost of land, labor, equipment, seed, or processing and profit to farmer and retailer. Sorry, that doesn't sound right. Staples (corn, rice, wheat, potatoes) certainly don't cost that much per pound. Legumes don't. Most fresh fruit doesn't. Milk doesn't. Cheese will, but some cheeses on sale won't. Vegetable oil doesn't. Olive oil might. Most meat will cost at least that much. Maybe the figure you quoted was just referring to meat or processed foods.
In any case, before you use figures, just make sure that number makes sense. (I am reminded of the time in college when as a grader in a physics class, the students were asked to find how high a pressurized leak on a water tank would shoot into the air. Two student's answers had the water at escape velocity speeds, sending them into orbit the earth.)