World's Most Energy Efficient Vehicle? A Bicycle

This is the sort of impact that Critical Mass rides around the planet try to demonstrate on a regular basis.

What's weird about Critical Mass is they feel they need to run red lights and stop signs when they do their rides. What about pedestrians? F'em, I even got caught in the middle of crossing the street once as they were coming around the corner, bikers on every side of me.

CM has a good point to make, except for the anarchy pov - which gets in the way of their very important message.

Efficiency is a matter of perspective. If your measuering watt in to work out, there are modes of transport better than a pedal bike. But it all depends on where it's measured from. From solar input (100% of all energy on the planet minus nuclear is ultimately solar) Any biological source is going to be lacking, since clorphil has a max efficiency of 6% (even cheap photo-electrics double that).

It may be easier to measure it in cost per kilometer. A litter of petrol may cost $1.75USD but it will take you 10k. that's $0.18 per kilometer.

After I finish a long bike ride I can EASILY put back that much in food, and then some. My BMR is about 2000Cal. Biking to and fro work, 30min each way, taking it easy at 20kph increases that by OVER 1000Cal. Now you can eat that easy with a few gulps of olive oil, but I like a bit more variety. To replace it with normal food I need to add 1 to 3 extra meals (IE. A bagel sandwitch). Making myself I MAY be able to make them for $1-2USD each, buying them on the road it's more like $5-$10 each. G_d help you if you eat health food. It would have only taken
$3.50 in petrol to make that distance.

OK That's not 100% of the story, since a car has upkeep and insurance, and being stuck in traffic does not do half for my day what a vigorus work out first thing in the morning does. I'm also saving time and money on a gym membership (a set of weights is all else I need). There are also lots of high carb foods, that don't cost an arm and a leg (pasta, whole grain breads, bannanas, peanut butter, etc..) Also, it's allot more fun 'gassing' up on pizza then worring if that snickers bar at the petrol station check out is going to make your waste line grow more than it already is.

In Sydney, CM most often ride with a bicycle police escort, and generally observe road rules. I agree that it's counterproductive to the 'share the road' message if cyclists show contempt for red lights, etc.

In theory a tandem recumbent bike would be over twice as good as a regular bike, and nearly as good as a train for people/hr. Add a solar panel powered motor assist and you can even better the efficiency of a regular bike for a couple of hundred $ more.

Just solve the sweatiness problem and we've got something!

Sorry, thelonecabbage, I don't follow your bike calorie math. According to the TreeHugger link, a cyclist would burn 420 calories for 20K/12 miles or 3/4 cups of oats. A 30-cent PopTart has 204 calories which gives you over 9K or $0.03 per kilometer -- or 1/6th the cost of your car example.

I remember seeing a similar calculation once (sorry, don't remember the source), only instead of comparing prices, they compared "gallons of petroleum used".

After all, the food you need to eat has to be harvested and transported, which is usually with petroleum-burning farm equipment and trucks. Bicycles are far more efficient and moving people than cars, but instead of putting petroleum in your tank, you're spending it making food, and then digesting the food for chemical energy.

Their conclusion was that bicycling is more energy-efficient if you're vegetarian. Meat, on the other hand, is so energy-intensive to produce that omnivorous bicyclists actually used more oil than driving a small car.

I guess it goes to show that you can't simply make one thing you do energy-efficient, and expect that to make a difference: you need to consider the whole system.

--
editor note: Even if you drive a car, you have to eat. Not quite as much as someone cycling a lot, but still...

I enjoy cycling and it is my
primary and favorite exercise.

I do some shopping and errands
via bike.

I have spent a lot of time in
the netherlands and greatly
appreciate it's bike friendly
environment, the many bike lanes
and path ways.

I have a friend or two in
the Netherlands who do not
drive, bike for all of their
transportation.

But from my own experience
and observation, in reasonably
diverse areas in the Netherlands, 28 percent of
urban transport is an absurd
exaggeration.

Where does your number come
from ?

Yes, Icelander. Sweatiness is a big obstacle to massive bicycle adoption.

I love my bike.
Lately, I've been riding around with a big patch on my back that says "Smog alert? STOP DRIVING!!"

Sweat could be solved with showers in the office. Make it mandatory as a part of a national energy program, or give tax reductions for companies that install showers.

I tried posting a trackback to this story, but your trackback URL is returning a 404 error message. Just wanted to let you know.

My post referring to this story is here: http://www.training-time.com/inspiration/?articleId=262&lang=en

Recumbent bikes are baloney.
You eat whether you drive or ride. The sweat issue is a lame ass excuse.

The 'back of the envelope' section of TheWatt podcast had some interesting maths on this a few weeks ago.

He calculated that the equivalent mpg of a bike (on a fairly long journey) if you compare calorific value was about 1150mpg.

This assumed he ate 8 bananas, but if you factored in all the petroleum inputs to get those bananas from the carribean to canada, it dropped to about 600mpg.

The frightening one was that if you had eaten a processed cereal in the morning to provide your energy, the sheer amount of energy, fertilizer and processing involved would drop your efficiency down to .................56 mpg!!!

Of course the guy in the car making the same journey after the same cereal would have a much lower mpg, but it just shows the impact of our food system.

The best solution is simply to avoid commuting whenever possible.

Why not telecommute? A large number of office professionals can work from home at least a couple of days a week.

This talk of cyclists needing more food is absurd in the US. I ride dialy, but eat no more than my friends and neighbors who are sedentary. In fact, , I regularly eat much less than some (yes, they're overweight/obese). If you look at the avg. American food intake, it's plenty to fuel a commuting cyclist with no increase necessary.

Yesterday I rode forty miles and my intake was a bowl of cereal for breakfast, an energy bar for lunch and a salmon burger, fries and sald for dinner.

Good point, Jim. Few people would have to eat any more than they already do, that is, they eat too much as it is.
Overweight/Obese people sweat more easily.

This is a quote from Ivan Illich's book Energy and Equity, published in 1973:

"Man on a bicycle can go three or four times faster than the pedestrian, but uses five times less energy in the process. He carries one gram of his weight over a kilometer of flat road at an expense of only 0.15 calories. The bicycle is the perfect transducer to match man's metabolic energy to the impedance of locomotion. Equipped with this tool, man outstrips the efficiency of not only all machines but all other animals as well."

Find it online at:
http://www.cogsci.ed.ac.uk/~ira/illich/texts/energy_and_equity/node8.html#SECTION00008000000000000000

Surely it's easy - walk or cycle if you can. If not, take public transport. Only as a last resort should people be driving to work (especially in a city) and they should never be driving great fuel guzzling vehicles - think of the environment, and your pocket, then decide how to travel! More often than not, the green route is also the cheapest route.

Thanks Kevin for that very interesting essay by Ivan Illich...

Of course! its basic physics people. In physics an engine is considered anything that takes a source of fuel and turns it into other forms of energy(motion, heat, exhaust)and when compared even to the most advanced technology our body still ranks an easy number 1, it amazes me not more people ride bikes in a country thats so 'independent'. Hey lemme all ask what you think of this idea. Ok gas in this country is at an all time high and so is obesity, well you know what I say..ride your bike to work!

In addition to the energy efficiency of the bicycle, there are many others:
there's the psychological benefit of not being stuck in traffic,
the health benefits of being physically fit,
the financial benefit (I save $7000 a year or $0.50/mile),
and the humanitarian benefit (according to USDOT, automobiles are the highest cause of death for children in America).
There are so many dozens of arguments to using a bike over a car, the only counter-argument is the myriad dollars from the auto/oil industry.

The sweat issue is a lame ass excuse.

Okay. Then try cycling to your date when it's 80 degrees and 90% humidity. You won't arrive smelling spring fresh, I can tell you that much.

I work up a sweat walking to work in the morning during the summer, but I get even sweatier if I ride my bike.

The sweat issue is definitely a legitimate concern. I have found that investing in a few shirts/jerseys made from sweat-wicking fabric is a great way to both alleviate the sweat problem and stay cool in hot/humid conditions. In addition, my girlfriend finds it sweet that I would ride 30 miles round-trip just to see her! (Lucky, I know...)

I'd be interested in thoughts on electric bikes. I know there are batteries that need to be manufactured and recycled, which costs energy and creates pollution. But, from a practical viewpoint, they offer quite a lot for commuters that may be interested in them only to save money. If they save the commuter money (and sometimes even save time), and save energy and pollution at the same time, the potentially green concept could be more easily generalized to people that are not naturally green thinking. Because of their low cost and savings on fuel, registration, insurance, maint., depreciation, etc, they make economic sense for the right commuter, and no sweating, either! I like the idea of these joining the bike world, as replacements for cars, not for bikes, which is where I think most of the interest in purchasing the e-bikes would be.

What's wrong with sweat and a good healthy human smell?

We US Americans are so afraid of humanity, it's sad!

If my date (or my husband) didn't apprciate my healthy lifestyle, I'd dump him :-)

Never mind the calculations and justifications, just ride. People who don't ride aren't going to be convinced by math anyway. You want an argument for commuting that people will consider? Show up at work on your bike with a HUGE smile on your face.

Put the fun between your legs and ride!

After wasting so much emotional hot air getting mad about oil wars and global warming and air quality in my city I've finally just let my riding to the talking.

I just love to ride my bike!

I love taking it to the shop and keeping it in tip-top shape for only, like, 10 dollars a month (tires trued and tubes patched, etc.). The sweaty issue takes care of itself as the shape I'm in is constantly improving.

I have enjoyed cycling for the past 17-18 years. My biking range extends from Gilroy to Sausalito (125 km), also Santa Cruz, Half Moon Bay, San Leandro, and Sunol-essentially all of the San Francisco Bay Area.

I can give you a good reason why to use an electric bike...
http://carsonatus.blogspot.com/2007/01/price-of-new-car-with-all-future-20.html
it's just too expensive to have a car...

Bicycles are great. You not only are efficient but you a connected with your environment. You can talk to people, wave, spit or whatever. It transends environmentalism. It is a life forming device. If you are in Strasburg, VA and need a bike to ride, check out www.halfmoonbikes.com, if you tell them you saw it on this site theyll hook you up with a bike to ride for the day, it may be a pos but it will be better than renting a car or driving yours if you have one with you.

Hi,
I don't mean to beat the topic to death but some input . . .
Sweat -
You have to change clothes. It's that simple. Investing in some decent (Descente?) bicycle clothes makes a difference. Get to know your size and buy stuff off eBay- saves a lot- use some bleach if you're squeamish.
You have to have a place to change from Superman or Wonder Woman to Joe or Josephine Average when you get there. I ride from Brooklyn NY to a midtown NYC bank. Lock up out front and change in the first floor bathroom. I am able to use the janitor's slop sink if I need to rinse. Hair is no problem because I have found those flexible ear band things to be effective down to -5 degrees.
Then there's an evolution process- my 11 mile ride one way can be done with no sweat in 55 minutes in 70 degree temps in the morning. You have to build up to it. I am 215 pounds and carry 25 pounds on my back. I used to be 240 pounds. I got down to 195 pounds but got careless and un-disciplined. Anyway, bring a change of clothes in a messenger bag (Manhattan Portage- made in New York State). Other stuff to bring- small pump, 2 tubes, tire levers, spoke wrench, chain and lock (do not skimp on these), hat, front light, rear light, clear glasses, sun glasses. Know how to change a flat tube- be self sufficient.
A good site for info is www.icebike.org for the warm weather challenged.

There's no time -
I agree, there's no time to work out. Sleep seems to be the new luxury of the rich. I can't telecommute as much as I'd like to. I also have to do audits sometimes as well. When I get out of work, I am beat. I used to gym it but holy crap, I am too tired to eat dinner at night a lot, getting up in the morning is a long process,... maybe there's something wrong with me,... anyway, my 50 minutes of cardio each morning and evening is my commute. You can go hard up the bridge for some anaerobic stuff. The subway is an hour plus walk and wait time. I got my boss to do the ride (only half the distance as mine) for a while and she pointed it out to me, the whole time management thing.

Dating-
She thinks I am crazy when I ride the 32 miles to her place up a few big hills.
A 5 minute rinse in the shower and all is fine.
Now for the round trip, 2 gallons of fuel- $5.8o, tolls- $15.oo, not paying $$ to terrorist oil countries, big oil, or the Triboro Bridge and Tunnel Authority or the Port Authority of NY & NJ = PRICELESS.

Critical Mass-
I read the times-up.org web site every now and then. They give out breakfast at the base of the Manhattan Bridge every last Friday of the month to get the word out about the Union Square starting point for the ride. I haven't gotten snarled - but then again, I rarely drive into NYC. I heard there was a transit strike last winter? Hmmm.
Another group which leans less on the civil disobedience is Transportation Alternatives- www.transalt.org . They concern themselves with promoting Mass transit, walking and biking.

I think it's less about anarchy and more about self sufficiency and independence. Or maybe just being a bit different. My favorite quote puts it like this -
Modern industrialized states [are] resentful of a few cleverly arranged pounds of tubes and spokes. The cyclist creates everything from almost nothing, becoming the most energy-efficient of all moving animals and machines and, as such, has a disingenuous ability to challenge the entire value system of a society. Cyclists don't consume enough. They can propel themselves 1500 pollution-free miles on the energy equivalent of a gallon of petrol. The bicycle may be too cheap, too available, too healthy, too independent and too equitable for its own good. In an age of excess it is minimal and has the subversive potential to make people happy in an economy fuelled by consumer discontent. Jim McGurn, 1994

Good Luck-
Just get out there and ride !

vsk

bicycling is poetic,
beautiful and rhythmic.
it puts one in touch with
nature: bird song, moving air,
terrain, light, rain and fog.
the car is a narcotic insulator.
it disconnects one from
reality and lulls one into
stupid somnambulence.
driving a car, like watching
television is a passive experience.
only a dolt loves his car.
drivers are dunderheads.
cyclists live in the moment.
cycling is like meditating.
it opens the spirit and the mind.

OK so my friend Bonnie introduces me to my new tennants. I kept bugging her- What can I do for YOU??
After a couple of weeks - "Hey I have this old bike, do you think you could get it road worthy again so I don't have to get another car to get back + forth to work?"

Now how could coincidence work any better?

A different Easter Sunday resurrection- old Raleigh Super Record 10 speed, what used to be an "old clunker college commuter" is now a "cool vintage machine".

vsk

Walking & cycling should be the only means of transit within cities. We should be looking at ways in which we can reclaim our streets from automobiles, investing in public transit and rezoning for multi-use. Much of our food can be grown locally where transportation is not nearly as big a factor. Pesticides, herbicides and chemical fertilizers are not needed for smaller scale organic farming, and contrary to popular belief, we can continue to feed the world without Agrobusiness and their poison.

In some response to WillySF,

There was a little front porch chit chat last night about neighborhoods turning around and gentrifying (or "expensive-ifying" if you ask me). There seems to be a renewed push to get back into the city. Hopefully the big MonsterUVs are starting to lose their appeal (I think their beefy suspensions would make for great electric conversions). Also time savings by not having to commute such a long way into the city from the suburbs. Anyway, intra-urban sprawl is definitely picking up, lots of neighborhoods have changed and are still changing. There was just a great clean up of Plumb Beach last Sunday by the American Littoral Society and others. The city could really shine if there was just some local pride. Now, riding to work these past couple of days has been interesting . . . where were all these people during my solitary commutes in January, February, and March?? The Brooklyn Bridge is amateur city, but the Manhattan Bridge with it's north side path closed looks like it could become quite dicey. I passed a few intersections with multiple bikes waiting for the light. After some rambling, my point is, I think there is going to be quite a lot more bike traffic this spring to fall. While it is great to see, I hope people behave themselves so restrictions don't start cropping up.
www.transalt.org is a good source for info.
Good Luck, vsk

Some interesting reading for a rainy day -

http://www.bikereader.com/contributors/mcgurn/McGurn.html#stories

Bike:

Food (type)

growth costs, fertilizer, transport costs, manufacture of parts, water processing costs. costs to market, transport to store, did you bike to buy that food? All that is oil that has been used in transport to get the banana to your mouth.

Car:

Fuel (type):

Drilling rigs, worker air transport, manufacture of parts, security personnel, oil tankers, petrol tankers, electricity used at the pump, the automatic doors, the lights in the station, the lights at the electricity plant to let the workers see, lights and computers in the accounting department so they know how to bill the petrol station, fuel for the postman to deliver the bill to the petrol station...

Yes, it can get quite complex, there isn't so much as a fixed list of costs for a set portion of fuel in your car, or that banana in your pocket (or are you just exci... no I won't).

So, there are no real fixed costs for 1km by car, and 1km by bike.

The car has a huge impact in production that lasts 10 years, until it is scrapped, and then junks up some land. The bike, well, that may last 10 years too, has less of an impact. Less services. Less oil changes. fewer tyre changes. Fewer bulbs and consumable parts and fuses that support entire industries.

The bike has less of an impact to buy, and costs you a few calories.

To move 100kg of bike and person (ok... 115...) using muscles chemical energy and oxygen, from calories obtained from various foods.

Versus, moving 1000kg of car, from refined oil, pulled from the earth, carried around the world, sent through an intricate chain of suppliers, to the pumps.

Both give off CO2. Which requires less, and gives off less?

That begs the question, which source of energy available for consumption is, today, the most eco friendly. eco, social, sustainable, ethical.

Not chocolate. Not cereals. Bananas? hrm.

Perhaps we need to really think about what we can eat.

Actually, an eGo scooter @24mph uses about 62% of the energy of a bicycle @15mph, so at the wheel it's more efficient than a bicycle.

Oat Meal is the new Oil !

Hi,

I am not sure I am getting your math Martin.
Maybe electricity to the wheel is more efficient than pounding the pedals?

Especially the speed differences. The air resistance at 24 mph is much more than at 15.

Looking at the site, it weighs 59kg. Maybe efficiency varies by user? Maybe by commuting distance? I use a regular road bike to go 11 miles each way into New York City and I carry at least 25 pounds each way because of lock, clothes, tools, tubes, etc. I can get to 26-28 mph on a straight road with no wind but maintain about 18-20 mph. Do you have a source for the statistic?

Good Luck, vsk

Electric Bicycles and Electric Scooters

Elmo The Electric Bike and Electric Scooter Guy

This is an excellent blog for electric bicycles. There are not too many around like this. Thanks for making this such an interesting subject. Oh, by the way, Wired Magazine has a great article on hybrid cars this month. (Jan 2008 issue).

God Bless,
Elmo

Hello,

i disagree with Ivan´s calculations in his book, here are 3 reasons his numbers are wrong:.

1) You can continue to eat normal and bike 40 miles a day, but only for a short time. The energy deficit will catch up with you in 1 to 2 weeks. You will feel tired and burned out. Not only that but food energy is a lot more expensive than petrol energy. If you dont you will simply get sick and waste your muscles away. Most people´s BMR´s are about 1500 calories a day, thats what it costs to simply stay alive. Tour de France stages are about 150 miles a day and they eat over 10000 calories each day to maintain it for a couple of weeks. For a 40 mile day you would have to eat a third of that if you were as a Lance Armstrong, but odds are your no Lance, so probably you will have to eat more, probably half or 5000 calories a day. Thats more than double what most people normally eat.

2) The human body is not an efficient locomotion machine. Most of the energy is used by the brain and the internal organs, there are a lot of complex tasks going on and walking or pedaling is not the most important of them. The common automobile is far more efficient than the human body in converting fuel to mechanical motion. It does only one thing and does it well. Most auto engines with compressions of 10:1 are about 30% efficient, and about 25% at the wheel due to power accessories sucha s AC, auto tranny etc.... The human body is about 5% efficient in converting food into mechanical energy, or 5-6 times less efficient than an old beat up car. It seems efficient because you have so little power output available, most people can sustain only about 150 watts on the average. If you do some basic calculations you will see the power density of automobiles is something like 10x that of a bicycle rider and actually use less energy per mile than ridding a bicycle does...

3) What most people dont realize is that the bicycle drive train is actually more inefficient than a auto tranny, bicycle chain drives are only 80% efficient on the average. When youre chain is dirty its even worse, an MIT physics dept test showed it to be about 75% efficient. Also the drag coeffcient of a bicycle is far worse than a car, more than double so about 10mph you´re using something like 80% of your energy to fight the air, which is ridiculously inefficient.

...Also bikes are notoriously unreliable and cheap. Tires only about 5k miles, alloy rims about a year. Spokes break often and are a pain to replace. Yes, these are far cheaper than paying gas everyday, but dont forget that when you are ridding a bicycle, youk are the fuel tank...

I’m sorry anonymous but I disagree with your calculations.

1) Is some one who rides 40 miles leisurely commute (coasting down hills etc) a day really going to consume half the amount as professional bikers riding high average speeds and riding up the Pyrenees. Do you drive your car full throttle to work every morning? Anyway I thought people with high metabolic rates (athletes) used more energy than average people (please correct me if I am wrong)

2) A cars transmission would not be more than 80% efficient; furthermore, cars are putting much more power through their drive train therefore wasting more. I.e. 20% of 135kW (my car) is 26000watts waste. 20% of 155watt (your figure) is 31watts waste. Simply comparing the work done in moving a 1500kg car and a 100kg biker to a destination.

3) You can’t use drag coefficients to compare a car and bike rider without taking into account the cross-sectional area. Cars are usually moving faster than bikes (when they are not stuck in traffic!) and drag increases as a square of velocity therefore a car uses more energy than a bike to keep constant speed.

4) In response to your claims that bikes are unreliable and cheap(?) My current bike is probably 25 years old. For most of its life it has been sitting in a shed rusting with no maintenance, about five years ago by dad put new tires, a cable and new grip tape on it. It then sat for another four years and for the last year I have been riding it pretty much every day. It has given me no problems, not one puncture and I haven’t spent any money on it. Cheap yes! Unreliable no! Yes maybe it needs new tires and pads in another ½ a year but I would suspect that you could make about 50 road bike tires out of the materials in one of my car’s tires.

One thing I noticed was that riding in built up areas got me to my destination quicker than driving and I only live in a city of 70000 people. The only negatives with riding I have found are road rage abuse from idiot drivers out the windows of their Bogan Mobiles and I’ve had two bikes stolen from me in the last two years which is why I ride a rusty one now. That’s just human crap....
Riding is brilliant!

The only way to transport without causing pollution is to ride a wooden bicycle, use a wooden canoe, or walk. It takes fuel and causes pollution to manufacture normal bicycles.

I'll take my chances with my normal bicycles.
Besides, I can't find any wooden bikes around here, ... and the ride is really stiff. And the potholes, ...etc.

It's only 28 degrees this morning, dry and sunny, where are all the bike commuters?

vsk

honestly.... biking is all in good fun and with gas prices now $3.50 a gallon i wish i could do it more often. But school is 30 miles away. Do that everyday and see how that effects your part time job wages and see what money you have left over for a social life, insurance, cell phone, ect. not to mention the matinence required. Ive been lookin for a solution to this and leaving my house 3 hours early at 4am just doesnt cut it.

suggestions?

I never realized that if I stopped riding my bike i would no longer have a need for food and thus saving it for the misinformed bike riders of the world. It would also make me safer as I would no longer have to run red lights and stop signs.

There's a classic article on the physics of bicycling in, I believe, the February 1972 issue of "Scientific American." I had a copy but over the years managed to lose it. Anyway, according to the article the bike is the most energy efficient form of land transportation known, this in terms of mass moved over a given distance per unit of energy expended. Only the supertanker does better. I don't know if the article is online. I looked but couldn't find it.

I find that when I am cycling I need to eat much more, drink much more water, and sleep much more. There is also the sweat aspect so I have to carry an extra set of clothes and need to add an extra two showers to my day. I do love biking, but it's too bad employment doesn't go out of its way to help reinforce the lifestyle.

I have worked as a full time bike messenger in Boston for over 2 years, riding 8-10 hours and 30+ miles per day. Oddly, my grocery bills have not increased, and I still only need one shower a night (and unlike some messengers, I do take hygiene quite seriously). Sweat is rarely an issue, as my body has become so accustomed to riding that I actually get more of a workout WALKING. My maintenance cost is well under $100/year (heavy-duty tires and no brake shoes to replace!). Yes, the manufacturing process of my bike ultimately resulted in pollution and the use of fossil fuels, but DUH! so did you car (x1000!!).

And on the topic of fossil fuels being used in the production and distribution of food:

Fossil fuels are used in the production and distribution of EVERYTHING - EVEN FOSSIL FUELS THEMSELVES! With that said, does it make more sense to eat food produced with fossil fuels, or to fill up your car with gas that was ALSO harvested, produced, and distributed through the use of.. more gas??

So, to summarize:

Riding (no not sometimes. ALL the time!) vs. not riding = no increase in food consumption. (And even if it did, it could not possibly compare to the fuel consumption of even the most ridiculously efficient cars)

Bicycle MUCH less wasteful to produce than car

Bicycle actually EASIER than walking!

And obviously, bicycle MUCH MUCH MUCH cheaper than car.

I think these benefits drastically outweigh the comfort advantages of a car.

Re: The sweat problem

I live in a hot/dry climate and have found sweat to be a minor problem. Wearing Lycra and riding at ~15 mph keeps you dry up too ~100, and riding in temps above 105 gets seriously uncomfortable/dangerous.

A quick scrub with a wet bandanna, fresh deodorant, and keeping street/work clothes in your pack until you get to your destination will leave you smelling no worse than anyone else.

The rest of the question about the car or bike being a more efficient method of transport seems easy. Look at the amount of HP a person can produce vs. that of a car. I believe a person can do about .25 hp. So a car is how much more powerful? Also, wind resistance increases exponentially with speed and cars spend most their time at higher speeds.

CM rides through stoplights because they do not want to divide the group AND having multiple groups causes more congestion than one big group that flows smoothly. How many bikes can get through one traffic light while it is green? 2000 bikes / said # = lots of time waiting behind bikes.

I couldn't agree more about the discussion about how many calories are used by a cyclist (vs the number of calories used by an automobile). It is pretty obvious that cycling is the way to go. This guy has done some eco-math on the bike v.s. car debate:

Bicycle

One thing I do think about, however, is our food supply (the source of energy for us cyclists). The problem with our food (in America at least) is how it is produced. Big agra business is "more efficient" in terms of costs... but due to its size there is a ton of waste. Also, due to the centralization, there are often huge transportation wastes.

We already know the ultimate form of transportation (bike). Let's get more local food (fuel)!

Hi, I want to leave a comment about those that argue bike commuting requires a large increase in caloric consumption and larger grocery bills. It does not.

According to national statistics, most people in the US travel less than 5 miles to work. A 10 mile round trip commute at 35 calories per mile is only 350 calories. This will hardly stretch most food budgets.

Also, this arguement misses the obvious health crisis in the developed world, obesity. Most Americans already eat far more than they burn off in a day. Two-thirds of Americans are overweight or obese and American's average food consumption is about 3700 calories per day. Even a steady bike commuter could not burn that many calories in a day.

Even with increased prices, food is still inexpensive in this country. To make up for that 350 calorie difficient of an average commute would only be a candy bar or two or a large bagel.

I regularly bike commute about 2-10 miles a day and eat about the same as I did before I started commuting. Bike commuting is not a competitive sport that requires a massive increase in calories. Bicycling is instead a low impact, daily activity.

Either you burn calories you have stored at which point you will eventually run out, or you have to eat more. There is no debating this. The energy has to come from somewhere.

In 2008, I biked to Oakland and Hollister. Hollister is 100 km from Moffett Field, where I work. Oakland is 70 km from Moffett Field, as is San Francisco. According to a heart rate monitor I had, I burned 9000 calories during one bike ride to San Francisco (Baker Beach).

Commenters are quite right to include the costs associated with producing food. You have to include all life cycle costs when doing a strict comparison in terms of energy effeciency. And despite some's claims that they eat no more food when they're riding, that energy has to come from somewhere.

Some point out that then you need to include the costs associated with manufacture and distribution of gasoline. This is true, although these costs are likely to be much lower than the costs of producing food because oil is already sitting in the ground in a highly concentrated form.

However, if you're going to do a "full" lifecycle comparison, you have to include more factors. The health benefits of routine cycling are often mentioned though it is hard to quantify that. The health detriments and costs associated with the pollution produced by cars would also need to be factored in as well as the costs of injuries and deaths that would not occur if driving was reduced.

Next, you would need to account for the reduced infrastructure required for bicycles. They take up less space so roads can carry much higher volumes, put less wear on roads, require less storage (parking), etc. This might be easier to quantify, though the benefits really only come in to play when you get a significant portion of car trips being replaced by bike trips. You can even make the arguement that everyone person on a bike is one less car on the road, which reduces congestion, which improves average speed of the cars, which improves auto mileage and saves commuters time, which makes them more productive and happier.

The $/mile comparisons are interesting, and point out how much variation there is in food costs. However, they don't account for the possibility that the true costs of gasoline are understated because we do account for all the shared costs of our current energy system. Health costs, military expenditures, infrastructure maintanence, etc. are all costs that we pay, but do not end up directly in the price you pay at the pump.

True lifecycle comparisons can become impossibly complex, but it seems a few obvious points come out without running every aspect of the math:
- Bikes are significantly more effecient than cars
- Where and how your food is grown has a huge impact (regardless of what you use that food for). Just because you're a cyclist doesn't mean that you can ignore that fact.
- The benefits of cycling go beyond simple energy consumption
- The benfits of cycling accrue not just to the cyclist but literally to every single person in the world.