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Comment by socialist_coder | Hacker News Reader

This should not really be very surprising as walking is not very efficient. You should be comparing driving to cycling, as both are wheeled forms of transportation. Cycling is up to 5x more efficient than walking (https://www.exploratorium.edu/cycling/humanpower1.html)

So, if you compare driving to cycling, cycling wins hands down. And, this is with the artificially low cost of fossil fuels. If fossil fuels properly factored in all the environmental damage, cycling's efficiency advantage would be even higher.

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Did you read the article? They compare bicycling too.

Also, a lot of fossil fuels are used grow and transport food the food you eat. It's not immediately obvious to me that the fossil fuel impact of growing the food, transporting it, and packaging it is less than the fuel to move a car in the first place.

If you're going that far perhaps factor in the costs of drilling and shipping fossil fuels on the other side ... admittedly it probably is a factor or so less than the proportion associated with foodstuffs - but - the foodstuffs side has plenty of room for optimisation whereas the fossil fuels side is on a degenerative trend

> Cycling is up to 5x more efficient than walking

"Up to" doesn't mean much. Biking is explicitly considered in the original piece:

> Surprisingly, from a pure energy perspective (using the methodology mentioned above), biking, walking, and running are the three most expensive types of transportation listed

Does it consider the health benefits and therefore reduced medical costs we would have if more people walked/biked?

Those people will probably more than make up for those costs later in life.

"Up to" is reasonable because it varies so much. Energy efficiency of cycling depends strongly on aerodynamics. A fully faired recumbent like you see in the human powered vehicle record attempts will do much better than a normal upright bicycle, probably better than 5x walking. Skin-tight clothing vs. normal clothing makes a big difference. Even shaving legs makes a very small but measurable difference. And because drag increases with the square of the air speed, aerodynamics is more important when you're riding fast. This contributes to the wasted energy on hills too, because you descend much faster than you ascend.

For these reasons it doesn't make much sense to talk about exact figures for energy efficiency of cycling without specifying what type of bicycle, what clothing, what weather conditions, what terrain, what braking technique, how much the rider weighs, their riding position, how fast they're riding, etc. The tires and the drivechain make a noticeable difference too.

Do you think the fossil fuel subsidies benefit the agriculture industry hence also making for cheaper food?

Modern food is packaged oil.

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