The Bicycle is the Most Efficient Machine on Earth!

To quote a wise man in big glasses and a sparkly top hat: And all that science, I don’t understand. It’s just my job five days a week.

Awhile back I wrote a blog about John Childress, a computer code writer and an aficionado of geeky-cool who had chosen to live in Madison sight unseen more or less purely because of the city’s great rep for biking. In the course of our conversation John mentioned that his background was in engineering and that he had done some poking around on the relative efficiency of biking as opposed to other less ennobling means of getting around.

Proof that bicycles are WAY more efficient than single occupancy motor vehicles.

He sent me a paper, much of which is Greek to me. Some of it (the symbols) is literally in Greek and all the rest of it is certainly written in geek. But here’s John’s point: it takes much less energy to move people or goods on a bike than on any other form of transportation. You already knew that but you might not have had the numbers. Now you do.

His calculations compare the following modes:

  • A Toyota Corolla with a standard gas engine is 1.8% efficient.
  • A hybrid bus running at 75% of capacity is 5.9% efficient.
  • An electric El train in Chicago at 75% capacity is 9.9% efficient.
  • And, are you ready? A bike is 80.2% efficient!

Bikes rule the efficiency world

Why are cars so inefficient while bikes are so stingy? Mostly it’s because cars are way too heavy and overpowered for the purpose. Most of the car’s power is expended on moving the vehicle itself and not its relatively light payload. That

Corolla, for example, tips the scales at about 2,800 pounds while the average American man weighs only 185 pounds – even in these days of the obesity epidemic. (The average American man would, of course, weigh less if he spent more time on his bike and less in his Corolla.)

I am that average man, weighing exactly that svelte 185 pounds, but most days I ride my fixie to work, which comes in at only 23 pounds. So you can have 2,800 pounds moving 185 or 23 pounds moving the same 185. There’s more to it than that, but that’s the basic reason for the stunning efficiency of the bike.

It all comes down to matching the mode to the purpose. Getting to work from my home in Madison to our downtown office just doesn’t require any more power and weight than my 23 pound bike. But I drive to our Milwaukee office because I can’t spend several hours commuting each way and I drive when I pick up lumber because that’s just the most practical way to do move that much bulky weight.

The lesson isn’t that cars are bad or unnecessary; just that we use them more than we have to in order to get the job done.

Turns out rocket men just burn their fuse up here alone.

About Dave Cieslewicz, Executive Director

Dave Cieslewicz served two terms as mayor of Madison where he set the city on a path for Platinum status as one of the best biking cities in North America. Before that he started his own nonprofit, 1000 Friends of Wisconsin, which focuses on land use and transportation policy. He has been an adjunct professor at the UW Madison's Department of Urban and Regional Planning where he teaches a class called Bikes, Pedestrians and Cities. He pronounces his name chess LEV ich, but nobody else does.

6 thoughts on “The Bicycle is the Most Efficient Machine on Earth!

  1. I have seen efficiency comparisons in physics texts, which without all the geeky explanation, usually pin the car at about 13% efficient, and bicycles at about 93% efficient. I think those are oversimplified, just figuring how much of the energy goes to forward movement alone. The method here, of figuring in the mass of the rider, is clever.

    The fun point, though, is where does all that lost energy go? Most of the losses are to heat and noise. In other words, cars do little but create noise and hot air.

  2. Lance, I might answer the question where does all that lost energy go, thus: CO2 (greenhouse gas). Also, I might ask where does all that surplus energy come from: fossil fuel; which is pertinent.

  3. Garbage.
    All that this formula illustrates (this is not a “proof” by the way) is that the bicycle, being very light compared to its load, converts the ENERGY THAT IT IS PROVIDED, most efficiently into motion.
    This is a useless metric. (and besides, a scateboard would be better even). To measure true efficiency, you must incorporate the cost of providing the appropriate for of energy. And humans are a very inefficient engine.
    A small alcohol-powered scooter, for example, or a large biodiesel bus, are more efficient, because they use more of the energy stored in their fuel. A human has to eat an awful lot of food to produce the same useable energy. So if it’d take two acres to grow sugarcane into alcohol into a scooter, you’d need four acres to grow enough human food to accomplish the same net work on a bike. Etc etc.
    Consider this also: a sailboat would be much less efficient by your formula, but would in fact need zero energy input from us. And would be infinitely (literally) more efficient than a .. canoe.

  4. Another way to say it: a bicycle is an energy efficient machine (because it really doesn’t do anything), but a very energy inefficient mode of transportation.

    In practical terms, you can move more people with less natural resources, using buses or scooters, etc

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