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Earth Transportation News

What's the Carbon Footprint of Bicycling? 542

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.'"
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What's the Carbon Footprint of Bicycling?

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  • seriously..? (Score:5, Insightful)

    by cyberstealth1024 ( 860459 ) on Sunday August 14, 2011 @09:33AM (#37084858)

    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

    • Re:seriously..? (Score:4, Insightful)

      by vlm ( 69642 ) on Sunday August 14, 2011 @09:38AM (#37084892)

      the carbon credits is just a way to make businesses ...

      ... more money. Yet another reverse robinhood deal, steal from the poor and give to the rich.

    • by Nidi62 ( 1525137 ) on Sunday August 14, 2011 @09:42AM (#37084926)
      Someone needs to come up with the carbon footprint of all these studies on the carbon footprint of x.
    • Life expends carbon, Hu-mahn! Carbon based lifeforms must die!
    • The carbon footprint thing is overrated, but not useless. The problem is that it is often used without context. Canada is replacing their paper currency with plastic, for example, and it has a much better carbon footprint, in part because the plastic does not break down and thus does not release carbon into the atmosphere.

      But that also means that what goes into the landfill does not biodegrade, and that we are using a non-renewable resource rather than a renewable resource for the money. (Even though it

      • The carbon footprint thing is overrated, but not useless.

        No it is useless because of the lack of consistency. For example in this study did they consider the food usage of someone sitting on a bus or driving a car in their study - I would guess not. In fact since generally our food usage is in excess of our body requirements the difference between a cyclist and passenger is probably not that great, not to mention the health benefits of cycling which will reduce health care needs and so reduce the carbon footprint of that. Hence you end up with some apparently sc

  • by Sporkinum ( 655143 ) on Sunday August 14, 2011 @09:38AM (#37084884)

    Since the whole carbon footprint thing is so grim, what way of doing myself in has least impact on the atmosphere. I was thinking of getting sucked into a jet engine, killing two birds with one stone as it were.

    • by Duradin ( 1261418 ) on Sunday August 14, 2011 @10:16AM (#37085146)

      Freeze yourself in dry ice in a water proof container and have that sunk to the bottom of the ocean. Your carbon will be sequestered.

    • what way of doing myself in has least impact on the atmosphere

      I would suggest perhaps dying in a mine collapse; then your decaying body would leech back into the ground and very little would make it back up to the atmosphere.

      The worst would probably be incineration in a giant kerosene fire.

      On that happy note, enjoy your Sunday.

  • By growing his bamboo bicycle frame into the shape he wants. Fairly cool! []

    • Re: (Score:3, Insightful)

      by evanbd ( 210358 )

      If it costs $2700, that implies there's a fair bit of energy going into making it, whether directly or indirectly. If that's mostly labor costs, what do you think those employees do with that money?

      Certainly there are greener and less green alternatives when looking at similar price points, but I don't see how spending 10x the amount on a bike could possibly be considered a "greener" alternative.

      • by Arlet ( 29997 ) on Sunday August 14, 2011 @11:40AM (#37085808)

        If it costs $2700, that implies there's a fair bit of energy going into making it

        Not at all. I'm guessing it's mostly labor cost and profits.

        If that's mostly labor costs, what do you think those employees do with that money?

        Probably the same things the customer would have done with the money if he hadn't bought the bike, so it doesn't matter.

      • by IICV ( 652597 )

        If it costs $2700, that implies there's a fair bit of energy going into making it, whether directly or indirectly. If that's mostly labor costs, what do you think those employees do with that money?

        It costs $2700 because these are basically prototypes; from the article, the guy talks about how sales have been growing in "double digit numbers" - they probably make less than a thousand of these per year. If they increase production, the price will probably come down.

      • by martin-boundary ( 547041 ) on Sunday August 14, 2011 @07:49PM (#37089818)
        If the Mona Lisa is worth about $700 million, that implies that Leonardo DaVinci used up a *huge* amount of energy to make it, whether directly or indirectly.

        That selfish polluting bastard!

  • Sounds pretty easy (Score:4, Interesting)

    by TheRaven64 ( 641858 ) on Sunday August 14, 2011 @09:45AM (#37084948) Journal

    I'd be surprised if there were many bicycle owners who didn't do 400 miles in one year, especially if they're using them for a daily commute. 2 miles each way every weekday will do that in 6 months. And bikes last for years. Mine used to belong to my father, who did 20 mile rides on it on a regular basis.

    The 'instead of driving' thing makes this a bit more complex though. I don't have a car, so most of the time I use the bike the alternatives would be walking or getting a bus. The energy usage of the bike versus walking is difficult - going in to town I need to pedal about three times to coast there. Coming back, there's a gentle slope where it's about as much effort as walking, followed by a steep hill where the wheels aren't much help and I have to lift the mass of the bike as well as myself up the hill. If I bought a car, then I'd have to factor the cost of producing the car into the calculations.

    • Here in the UK I would reckon that most bicycles are or occasional leisure use. I agree that bicycle commuters and cycle couriers will easily do 400 miles a year, but I reckon most bicycles hardly ever come out of the shed between Sundays, and then only in the summer.
      • I live in Portsmouth. We have lots of cycle routes and many, many people who cycle everywhere. Admittedly Portsmouth is a relatively small city geographically, but biking is a very popular option for getting around here (especially given the absurdly tiny initial and ongoing investments for a cycle compared to a car, and the absolutely insane parking problems we have here).

      • Certainly in London I'm seeing a lot more cycles on the roads than in the past. Perhaps it's because the cost of public transport is always increasing.
    • because just like with motorcycles... one day its too hot, then its too cold, oh I am late, its raining or will, snow?!?!, rabid weasel alert, and so on.

      People make all sorts of wonderful justifications but most never stick with it. Many also don't have the opportunity to ride to work. We usually settle down and work where we can especially in a market like this. Let alone having a job where riding to work and being able to clean up is a possibility.

      • by epine ( 68316 )

        People make all sorts of wonderful justifications but most never stick with it. Many also don't have the opportunity to ride to work.

        The average person rigs the outcome far worse than that by favouring modes of urban development and taxation that create a warm, fuzzy, happy place until someone mutters "peak oil" under their breath.

        Peak oil is a stupid phrase. It doesn't exist to describe the world, where the situation resembles more of a plateau, but it is useful to poke pins into the psyches of people who

  • Flawed (Score:5, Funny)

    by kmdrtako ( 1971832 ) on Sunday August 14, 2011 @09:46AM (#37084960)

    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.

    • Or you could just exercise on your way to work, saves time too. :) (or if its too far to bike, bike to a train/subway station or bus stop and use public transit from there.)

      • There are no buses, subways, or trains that go anywhere near my office. The most direct route is 17 miles on freeways and what I consider to be bike unfriendly roads. Getting there on a bike on friendlier roads is probably more like 20 miles, and is probably at least a two hour trip each way -- not really how I want to spend 25% of my waking hours each day. Not to mention the prospect of riding 20 miles in a blizzard leaves leaves me cold, even if that's only a potential problem two months out of the year.


    • Guess I better stop riding and turn into an obese blob for the sake of the environment.

      For the sake of the environment, you'd need to stop eating too, since that has a carbon footprint.

      The whole idea is ridiculous because all paths lead to the ultimate conclusion of ending it all and saving the world from your carbon footsteps.

    • Oh noes. Guess I better stop riding and turn into an obese blob for the sake of the environment.

      Clearly you are trying to be funny, but it is still worth pointing out that - despite what many Americans may believe - lack of exercise on its own does not automatically turn one into an "obese blob". One becomes a blob through a multifactorial process of poor diet and lack of exercise (as well as other factors).

    • Re:Flawed (Score:4, Insightful)

      by hawguy ( 1600213 ) on Sunday August 14, 2011 @11:59AM (#37086004)

      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.

      But you need to look at the *net* carbon footprint. If you didn't bike for exercise and instead drove your car to the gym to ride an electrically powered exercise bike, then you still have a net reduction in carbon footprint.

      This study isn't telling you how to have a zero carbon footprint, but just telling you the carbon footprint of some alternatives. No one can have a zero carbon footprint, but (at least in the USA), there are many things people can do to reduce their carbon footprint to match that of other developed countries. The per capita carbon footprint of the USA is about twice that of the UK.

      Even if you don't believe that CO2 contributes to global warming, most of the USA's energy use comes from oil, which means vast quantities of money flowing out of our country, much of it into the pockets of regimes that aren't exactly aligned with our interests.

  • by AngryDeuce ( 2205124 ) on Sunday August 14, 2011 @09:50AM (#37084990) 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?

    • by Latent Heat ( 558884 ) on Sunday August 14, 2011 @10:27AM (#37085226)
      "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. "

      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?

      • by AngryDeuce ( 2205124 ) on Sunday August 14, 2011 @10:46AM (#37085366)

        There are shitty riders out there, just like there are shitty drivers. There are even shitty walkers, too...I've spent upwards of 20 minutes at various lights all over the downtown area because I had the bad luck of being at that intersection during change of classes and the 12,000 students in the building started streaming across the street whether there was a WALK symbol or not.

        I will be the first person to cheer when they put crossing guards at every intersection that can ticket people for jaywalking and ignoring the laws concerning biking in traffic, believe me. But I'm not gonna advocate building retaining walls around every sidewalk in the city to prevent it because that's ridiculous, just like how I would never just drive through the red I've sat through 18 times because the kids changing classes couldn't care less about the light because pedestrians have the right of way no matter where they fuck they are.

      • by MarkvW ( 1037596 )

        Don't overgeneralize. The same jerks that ride their bikes like asses are the jerks that drive their cars like asses.

        I understand your sentiment. A cyclist should treat a pedestrian like the cyclist would want to be treated by an automobile.

        The cops should ticket the cyclists you describe.

      • by filmmaker ( 850359 ) on Sunday August 14, 2011 @11:14AM (#37085606) Homepage
        It's been years since I've logged into Slashdot and commented, but I have to say a few words regarding cyclists. I live in Tucson, Arizona, one of the better cities in the U.S. as far as bicycle lanes and places for cyclists to ride. I don't ride a bicycle; I don't even own one. I'm a runner, and I often find myself running along the side of roads, including in bicycle lanes. Over the course of the last four years, I've never had a bicyclist who wasn't courteous, usually yelling "runner!" to those coming up behind them. Cyclists have always given me plenty of room, and I've heard plenty of "doing good!" and other comments of encouragement from them, as they pass me. Likewise in higher traffic areas, where there are traffic lights, cars and pedestrians, I've seen (with just a few exceptions) cyclists obey the traffic laws and ride courteously around pedestrians. The problem, at least here in Tucson, isn't cyclists. The problem is the motorists. Somehow I get the feeling this is the case in every city in America.
    • I do find it stupid how people seem opposed to getting off fossil fuels etc because "it won't help". Yeah... but how about we not burn fossil fuels and drive everywhere because pumping noxious gases into the atmosphere and slowly getting fatter are bad things?

      That said, I've seen plenty of inconsiderate dickish cyclists who cycle on pavements and such. Of an evening I usually walk for exercise along Southsea Esplanade in Portsmouth (esplanade = long paved section alongside the sea), which itself has a long

    • The hostility comes because most green initiatives involve the use of force. Either force to collect tax money to be wasted on things that are never used like many mass transportation systems. Or force to hike up the prices of things people want to use like gasoline. I have no problem with environmentalists that live their own lives and use them as an example. When they use force to make other people bend to their will is when I object.

  • We live in a system where our living causes carbon to be outputted. The point should be to reduce that footprint so the natural sources can take it out of our atmosphere or do whatever with it. The carbon footprint of a bike vs a car is crazy different. Hell I don't think most people realize that buying a new car instead of fixing an old one is better for the environment. The summary even goes to point out that walking isn't carbon neutral. DUH growing food costs energy. Sometimes I wonder how people can b
    • by Rennt ( 582550 )

      Hell I don't think most people realize that buying a new car instead of fixing an old one is better for the environment.

      I'll spare you the "fixed that for you" but you totally got that backward.

  • I bought a used bike.

    Additional benefit: I can leave it outside in the city all the time without worrying about it being stolen.

    • I usually just steal a used bike when I'm in the city.
      • Like I care. Not only is my bike unattractive enough to discourage stealing, it was also cheap enough that I can replace it many, many times for the price of a similar new bike.

  • My habit (Score:3, Interesting)

    by tepples ( 727027 ) <<moc.liamg> <ta> <selppet>> on Sunday August 14, 2011 @09:54AM (#37085014) Homepage Journal

    you would have to ride your bike instead of driving for around 400 miles to cover the bike's initial carbon footprint.

    And my 11 mile round trip to and from work? Already covered in two months of the first year.

    Bikes also damage roads far less than cars do. A heavy bicycle weighs around 30 pounds

    Slightly misleading, as it doesn't take into account the 170-pound rider on the bicycle. But I've read that the damage done to a road by a vehicle is somewhere between the third and fourth power of the weight per axle.

    My current way of getting to and from work is a bicycle during good weather or an off-peak bus during rain and during late fall and winter. But the article says off-peak buses are horrid. Should I change it?

    • The city is going to run the bus anyway - your best bet is convince other people to ride the bus with you.

      • Re:My habit (Score:5, Insightful)

        by Trepidity ( 597 ) <{gro.hsikcah} {ta} {todhsals-muiriled}> on Sunday August 14, 2011 @10:43AM (#37085344)

        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.

  • Bicycles don't have feet.
  • To say "walking isn't zero" is an obvious case of having an incorrect measure. A human needs food energy to exist. The increase in food energy used for the human to walk isn't necessarily a subtraction from the input. The human might eat 3 big macs a day. Just one of them might be necessary to fuel the humans walking energy needs (I'm assuming the walk less than 100 meters per day). if the human eats 3 big macs per day; walks monday through friday but does not walk for the rest of the week there is no

  • Does not compute (Score:5, Insightful)

    by TrumpetPower! ( 190615 ) <> on Sunday August 14, 2011 @10:21AM (#37085184) Homepage

    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?



    • Not that I agree witht the article... but I think they are assuming you already own a car... and are thinking of buying a bike to be "greener".

      In that scenario you've already expended the carbon for manufacturing the car and they are trying to tell you how much you would have to bike to break even on carbon after purchasing a bike...

    • by rtaylor ( 70602 )

      They began with the assumption you still bought a car so the bicycle was additional.

      The math is quite different if you buy the bicycle instead of a car.

  • Ride the wave, get some public exposure, but in the end they just spouted some rubbish.

    I wonder what the carbon footprint of all that fake research is.

    • I wonder what the carbon footprint of all that fake research is.

      I would like to know what part of it you think is "fake", and why. If you actually read the links you can get to the sources for their research, and how they arrived at the numbers mentioned.

  • While it's true that the production of food used as fuel for the biking (or walking) creates carbon emissions, you have to balance it against the need to exercise. So you should compare the carbon emissions for the driving plus the carbon spent on exercising at the gym to balance things out. (Of course, some people don't exercise, so you should add in the carbon emissions of the hospital stays after their heart attacks or strokes...)
  • Here's a novel way to reduce your commute carbon footprint by 20% or even 40%: Work from home one or two days a week. I WFH 5 days a week. No commute. No A/C. Almost no showers. What could be greener? Now, if I could only find someone to pay me money for this work...
  • 'Food production creates carbon emissions.'

    luckily photosysthesis eats up some of that carbon...

    The world cannot be completely 0 emissions or all the plants would die off once the CO2 is all gone.

    (But yeah, we still need to reduce the amount of CO2 we pump out)

  • than the blood splatter with ancillary innards.

  • Dead people have a smaller carbon footprint. Cycling in the current 107 degree heat through heavy traffic is a sure way to achieve that reduction.

  • Therefor, 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.

    So building a car has a zero initial carbon footprint? Seriously, I consider myself to be a pretty environmentally friendly, but these studies are ridiculous because they imply that we shouldn't put out ANY carbon into the atmosphere. Well, why don't we just wipe out all life on earth then? What we should be more concerned about is carbon balance. If we produce carbon emissions, we need to find a way to convert that carbon back into a non-gaseous form. Without industrial production, plant life can easi

  • What's the carbon footprint of reading yet another absurd study on carbon footprints?

    It takes less to build a bicycle then a car. It takes a lot less to power it. As a bonus, the human powering it gets exercise while doing so (which a lot of humans really need). We really needed a research grant to figure this out?

  • The only solution to the carbon problem is to exterminate the population and leave the bodies out so that you don't leave a carbon footprint trying to bury them. Turns out the nazi's and the khmer rouge were more green than greenpeace!
  • I'm a skeptic when it comes to climatologists having the forecasting chops to make the claims about what's going to happen 20-100 years down the road so carbon footprint calculations strike me as a cultural activity that'll be regarded as something akin to arguing about how many angels could fit on the tip of a pin.


    Based on my personal expenses, bike commuting and car commuting work out to be about the same. I'm old fashioned enough that I figure carbon costs are a proxy for energy costs and energy cost

    • by Arlet ( 29997 )

      Sounds like you have seriously messed up costs for your bike. I take my bike in every year to the bike shop to have it checked and fixed, and that costs about $40 each time. A flat tire I can usually fix myself for $1 in materials.

      A similar yearly checkup for my car costs several times that amount. Insurance is even more. That's without even considering gasoline.

  • by eepok ( 545733 ) on Sunday August 14, 2011 @11:12AM (#37085582) Homepage

    The article over simplifies the concepts of sustainable transportation and calorie consumption in the same ways thinly veiled "anti-green" articles attack more sustainable forms of energy production. In the energy debate, there are arguments against solar because of the lack of sun in Seattle, arguments against nuclear energy because of the waste that would be created if the entire world was put on nuclear power, and arguments against wind farms in natural wildlife reserves. They use worst-case scenarios to judge methods of alternative energy creation instead of how they would actually be implemented.

    The same goes for sustainable transportation and this article. FTFA: "If you walk 1.5 miles, Mr. Goodall calculates, and replace those calories by drinking about a cup of milk, the greenhouse emissions connected with that milk (like methane from the dairy farm and carbon dioxide from the delivery truck) are just about equal to the emissions from a typical car making the same trip." And that assumes I'm going to drink a milk. From a cow. After a warm walk. Who the hell drinks milk after getting sweaty? People drink water or have some fruit! Instead of postulating what the worst can be, why not survey people to find out what *actually* happens? Or worse-- why bother considering food at all?

    Even in the "worst-case" scenario where everyone in the USA stopped driving private vehicles and just rode bikes and public transit as necessary, would we all focus on beef to make up for our additional caloric needs? And would it make such a massive hit to the environment when compared to to complete loss of people buying and driving their own cars? -- Not that I'm advocating such pie-in-the-sky thinking, but if you want to bring in cow-pollution, let's really compare it to the pollution from manufacturing, transporting, using, and disposing of cars. I can be disingenuous, too!

    Lastly, focusing only on the mythical carbon footprint or GHG emissions of any mode of travel is BS science. It's only for "wow" and "fear" effect. You have weigh to the relative benefits of a mode for the passenger, operator, and third parties (cost, health, pollution, etc.), and the habits that may come along with regularly using a mode of transportation (lethargy and car driving for example). There are entire schools of study on sustainable transportation and summarizing it in a childish (trollish?) article is silly.

    It's not about finding single a form of transportation that is a "winner"-- it's about finding a mode that is best for you, where you are now, where you need to be, and when you need to be there. Sometimes driving your truck alone on the road is sensible-- like when you're heading over to buddy to help him move. Other times, it's stupid-- like when you drive 3 blocks down the street to pick up some tic-tacs.

    Regular Trips:
    Walking is suggested for round trips under two miles -- It helps keep the person healthy and burns no fossil fuels in the process. When you get home, don't raise 40 cows for slaughter.
    Bicycling is suggested for trips for round trips under 15 miles (fitness and competency varying) -- It helps to keep the person healthy and burns no fossil fuels in the process. See above comment about raising cows.
    Bus Transit is suggested for round trips under 15 miles or longer trips depending on availability-- It burns fossil fuels, but it's like a giant carpool.
    Train Transit is is suggested for round trips over 30 miles or longer trips depending on availability-- It burns fossil fuels (directly and/or indirectly), but it's like a giant carpool.
    Carpooling and Vanpooling is suggested for 20+ mile commutes -- It reduces the amount of pollution per user in areas where transit is not an option

    Irregular Trips
    Carpool (see above)
    Passenger Jet - In a packed jet and for trips greater than 700 miles, you're actually doing pretty good when it comes to your share of greenhouse gases. The longer the trip, the better since the largest concentration of fuel burning comes at take-off.

    You al

    • Walking is great, but most suburbs were built around the car and thus aren't very walkable communities.

      Which leads to an inevitable conclusion: Don't live out in the suburbs if you want to have a low carbon impact.

      Especially if you're single, the one choice you can make that will have a gigantic impact on your CO2 emissions is living very close to your work, or at least close to your work via public transit. Even without the environmental benefits, it often gives you an hour of your life back every day. If you have a family, this obviously gets more complicated, but it's still something to think about.

  • I mean, how many angels can balance on the head of a pin ? To argue that bicycles are , in any sense whatsoever, as polluting as cars, is just silly. Smart doesn't equal wise

In less than a century, computers will be making substantial progress on ... the overriding problem of war and peace. -- James Slagle