Guest post: The carbon footprint of cycling


Originally a comment by AJ Milne on Stop all that reckless breathing!

I got thinking a bit about the carbon footprint of cycling a while ago; I do cycle to work now and then (at 28K, kinda a long haul, and annoyingly, I can’t fit the time in right now, due to other parental duty things, but I probably will be again in a week or two)…

What I was generally hearing (with the billion hedges/estimates you need to build in in our annoyingly complicated economies–and see one high-level estimate here): it’s almost always better to cycle (and I drive a Prius, which is pretty low impact, as cars go). But depends a bit on what you’re eating. Some foods, if you count transportation and the way they’re raised/grown, are pretty high impact, so probably, counting all that, you can wind up making more CO2 that way, but it would be an unusual meal…

… and, generally that would be because someone drove or flew the food to you, which you then ate, and when cycling, then burnt it to CO2. That last burn really wasn’t the problem (and note that that carbon, specifically, was pulled out of the atmosphere to make the food, at some point; it’s carbon effectively in a cycle). It was the stuff involved in moving the food, which, sadly, yes, generally isn’t in a cycle; that’s the stuff we’re pumping it out of the ground and burning. And, yes, some foods are otherwise a lot more carbon-intensive even to raise, since little of the carbon involved winds up even on your plate.

Also kinda amusingly, I guess: with gas prices where they are around here these days, I figure the calories probably usually wound up costing me about as much as the gas would have. But, of course, there are also a lot of other benefits to cycling. And I’m pretty sure none of this builds in the carbon impact of the healthcare system housing me years longer, if I don’t get some cardio somewhere, at least.

Comments

  1. Al Dente says

    someone drove or flew the food to you

    Flying is the most expensive means of transportation. No food, even expensive items like spices and lobster, are flown. Most food that’s shipped any distance is moved by train or water, the two cheapest means of transportation. Most truck movement of food is local transshipping from and to rail and harbor facilities.

  2. says

    Re #1:

    No food, even expensive items like spices and lobster, are flown…

    While the very point of that construction of mine you’re referencing was to emphasize this is an unusual situation, and rather an extreme example, and I can’t at all claim to be an expert, I’m pretty sure air freight is, in fact, used in food supply chains, if at a pretty low volume against other means of transport. You can find a handful of papers assessing the impact of doing so. Example here. This, on the other hand, has a certain odour of ‘industry puff piece’, about it, and I’m thinking tens of thousands of tonnes of food in a year really isn’t much for a market like the UK, but still, you can’t quite say it’s never done.

    And remote communities in Canada’s north absolutely get some of their groceries by air, this I happen to know directly though people who’ve lived there, though you can also find online references.

  3. alqpr says

    This post is quite misleading. Cycling is not “almost” always lower-carbon than driving; it is *absolutely* always at least ten times less carbon intensive. There is no level of human activity that generates CO2 at more than a tiny fraction of that put out by a car – even when the engine is only idling to charge the batteries. And even someone who subsists entirely on air freighted Atlantic lobster on the West coast would consume negligibly more of it in order to cycle rather than to drive.

  4. says

    alqpr:

    Y’know, one of the reasons I’m not on the net so much anymore is I was starting to figure my compulsion to correct every little Wrong Thing On The Internet was becoming a mite unhealthy. Even when they were wrong about actually pretty important things, you really do have to know when to say, right, just let them be wrong, then. I should probably be doing something that feels less like beating my head against a wall. And as the post above was a single blog comment tossed off some days ago, yeesh…

    … still. Indulging my obviously pathological SIWOTI syndrome:

    1) No, it’s not a negligible difference, what your body burns bicycling versus driving, certainly not at any speed and distance. My commute by bike is a little under 2 hours, about a 50 km round trip*, and to do that in that time with traffic (which is still stretching what’s practical in my schedule; two hours is a long time to be neither with your children nor at your desk), I have to set what for me is a pretty aggressive pace. My normal daily burn is about 2200 calories. That commute alone is probably around 1700 calories on top of that. That’s about 75% on top of the normal, something I very much notice on days I do it (it’s a huge pile of calories, relative to what I was used to; I find it difficult even to get them). I don’t, for the record, eat a lot of air-freighted lobster. Or even any (I don’t like lobster, and, in general, it’s gonna turn into an awfully expensive undertaking if I get all those extra 1700 as luxury foods). But, if I did, and if you tried to account for externalities the way the linked article tries to do, they could easily become quite significant.

    2) The reason I bothered looking into this stuff at all was, in fact, my commute is two hours by bicycle, counting both ways. (And, no, I’d really rather not be working that far from where I live, didn’t used to, before about a year and a half ago, but such is modern life, apparently. I like the job. I hate the commute. Or I hate that I have to commute. I hate that if I’m going to put a roof over my children’s heads and get them through university, with my skillset, that’s probably the best move I can make right now, but anyway.) Anyway, a two hour commute by bike for me (it’s more like 45-70 min by car, more variable because the traffic is more variable) was pretty much a moon shot undertaking, when I first considered it, so I did look some into what sense it made, what it would cost, what it would gain, so on. Obviously, I do it, so I do judge it absolutely worth it. You might think about that, before you start grumbling about ‘quite misleading’. Or try considering the whole thing, and the attached article. And realize that, yes, our society is complicated, and just boiling things down to ‘well, it’s 10x better, on average, with the right foods’ might not cut it for someone burning that kind of time and effort, and who might also want some more precise idea just how far ahead it does get us. Oh: and just which are the right foods.

    3) Speaking of: the real point of the whole thing the way I see it is: try to be responsible about food choices, and keep in mind that there are impacts beyond the obvious to most things. I wouldn’t call myself fanatical about it, but I try to keep it in mind, with everything else I have to keep in my mind these days. As, again, how I get those 1700 calories does make a difference.

    4) One conciliatory note: while I don’t think it’s ‘misleading’, read and understood in its totality, the one thing I would change in that comment that became a post was: I’d use the adjective ‘significantly’ (or even ‘vastly’) in that bit on cycling usually being better. Because yes, and as per the attached article, it absolutely is, on average. But, again, there are catches and caveats and qualifiers, as with all things in modern life. But, speaking of ‘misleading’:

    5) Your claim ‘*Absolutely* always at least ten times less carbon intensive’ is not just misleading. It’s actually wrong.

    However: my overall point remains, in case this is still not clear: yes, cycling is a very good move, carbon emissions-wise. There are weird outliers where certain single trips not be, counting those externalities. But sure, I’d consider amending ‘almost always’ to ‘almost always vastly’ a friendly amendment, anyway. However innumerate the basis of the complaint may have been.

    * 25 each way, normally, not 28, as in the article, as long as I’m correcting things on the internet. Just checked it on my bike computer. There were a few 28 km rides, earlier on, when I was still working out the smartest/safest/least-choked-by-car-exhaust way, though, but I’ve since mostly worked it down to and settled on a route that’s 25, garage to office bike rack.

  5. John Morales says

    [OT]

    AJ Milne,

    … still. Indulging my obviously pathological SIWOTI syndrome: [due indulgence]

    I find your due indulgence severely restrained, but I assure you it’s duly appreciated.

    Thanks. 😉

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