Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

How are you defining efficiency here? Is walking really more efficient than cycling? I would put walking as the least efficient manual powered methods mentioned.

Aside: I used to unicycle to work, and I have to say that it was both fantastic and much faster than walking while on a 27.5" wheel.




Bicycles are like 98% in terms of distance/effort so even when you factor in the manufacture/materials it seems like it's pretty hard to improve on.

When you account for calorie transport it's possible the e-bike comes out on top, especially if charged from a local renewable electricity source.

[]: https://pedalchile.com/blog/cycling-vs-walking


at a micro level that's probably true, but from a public policy perspective, I'm willing to bet that regular bikes effect to increase fitness probably saves more carbon in the long run (healthcare is pretty calorie intensive).


Most ebikes you have to pedal to make them go. Some just push the throttle, but most are motor assist but if you don't pedal you don't go. As such most ebikes give the same fitness benefit but let you go faster (read farther). My ebike almost forces me to work harder than the regular bike as because it is heavy it feels like it doesn't coast as nice as the regular bike, and so I'm pedaling more. (part of this is probably I'm going faster and so wind resistance is lowing me down more - but to me it feels like I have to work harder to make the ebike work, in return I go farther on it)


> As such most ebikes give the same fitness benefit but let you go faster

This is simply not true. A pedal-assist bike will go faster with the same amount of W put into the pedals, yes. But will people put in the same amount of W if 60 % will get you to your "target speed"? I doubt it. And then you get less health benefits for the same distance traveled.

On my 8 kilometer commute I average 150 W. Not because I use it as exercise. That's just where I find my comfortable level of output. Every time I've ridden on ebikes I've put in much, much less effort. I'd be surprised if I put in even a third of the energy. That's great if you just need a mode of transport. Bikes are practical, efficient, and planning for them improves cities. Even ignoring the potential health benefits. But claiming that a pedalassist bike gives the same fitness benefits just doesn't pass the smell test.


I can only state for myself that I'm putting more effort in (since I can feel the bike slow down more when I don't). Plus the ebike allows trips that because of distance I wouldn't use the regular bike for.


From a public policy perspective, we've had bikes for eons and usage has always been minuscule and now we have ebikes and usage has jumped. So that particular experiment has already been run.


Yup, IIRC in terms of kJ/km cycling is ~4x more efficient than walking (on flat surface). I guess they must be talking about the energy used in production, etc.


It's closer to 6x.


I mean, the number will really depend on how fast people are biking. Over 20mph, efficiency starts to really take a hit. Unless you use some sort of crazy shell.


Cycling anywhere near 20mph is beyond most peoples physical capabilities... with the small exception of steep downhills where the energy is "free" (at least compared with walking where you capture none of it) anyways.


I used to aim for an average 20mph over my rides when I was in peak fitness, so putting it “beyond … physical capabilities” is nonsense.


"Most people" aren't in peak fitness...


There is another dimension to add: how far do you really "need" to go and how frequently. And why it is so? Remote working vs commuting, local/nearby enough shopping vs long distance for supermarkets, going yourself vs (maybe electric) delivery.

If everything around you is built with base assumption that you must have a car, then the optimization was done by someone else with a different definition of efficiency.


Yes. This is the difference between mobility and access. You can watch a movie by driving to Blockbuster in a SUV and physically picking up an optical disc. Or in an EV. You could bike there. Or get it mailed. If you watch on Netflix you access the commodity without any transportation at all.


Life is a compromise. I'd love to own 100 square miles of land, with my front door on New Yorks Time's square. That isn't physically possible, but it is what I want in the ideal world. (I don't live near New York so I don't know if times square is really where in New York I'd want to live, but it is an iconic place that at least gives the sense of what I mean - you could pick downtown of most large cities). Cars enable more people to have both the benefit of rural life while also getting the benefits of the city.

This isn't unique to cars - trains could give the same, but we already have a road network.


> That isn't physically possible, but it is what I want in the ideal world.

I think the same can be said (to a lesser degree maybe) about cars, which are very space inefficient. With enough sprawl and a certain density, e.g. in Toronto, it's just gonna be traffic for every one.


Not exactly. Sprawl means you can't reasonably reach the entire city, but low density sprawl and cars mean you can reach enough of a city to consider it all the advantages of a city. Toronto loses out because they have a dense city center, downtowns have to be torn down for the sprawl model to work - people who get a new job may have to move elsewhere in the city since the new job isn't close to the old (unlike when all jobs were downtown) However since you are still "close" you can visit old friends and family on weekends - it will be a long drive but you don't make that trip often so it is reasonable.

Cars don't enable many people to own 100 square miles - but I can get pretty close if I settle for 5 acres in an exurb. Many find that a single family house gives them close enough (they get a small garden - most likely grass they mow weekly - which is all they really want). But again it is a compromise. If we had science fiction technology (terraform Mars and Venus; teleporters) that 100 square miles might be reasonable.


I did not make my point clear, and that's my bad.

Torotno exists, so of course car dependency is somewhat feasible in real life. The impossible part is travelling in the sprawl with relatively short time, as limited by the road's speed limit. The real limiting factor most of the time is traffic, because of the space inefficiency of cars.

I made this point because I seem to recall a city simulation game despawn cars (literally physically impossible) to make car dependent designs "work".

---

> you can reach enough of a city to consider it all the advantages of a city

With enough people driving downtown you lose most of the advantages, and it makes the lives of those who didn't choose this lifestyle worse.


What does a salmon have in common with a man on a bicycle?

They are both Pareto-efficient. Here's a chart of cost of transport (calories/gram/km) vs weight (kg) comparing a salmon vs a bicycle vs a jet fighter etc: https://www.bike.nyc/wp-content/uploads/2017/04/efficiency-g...


When is that measuring the salmon? Surely, calories per gram per kilometer is very high if you're swimming upstream and low when you're going downstream, right? Is this when they're in the ocean phase?


Fun! But how to read the Y axis? Why does it start from 1 twice?


it's a logarithimic scale [0]

Those go 0.1, 0.2, 0.4, .. 1, 2, 4, ... 10, 20, 40...

I am guessing they printed "0.1" as ".1", and because it's a really bad scan the ".1" and "1" look identical.

[0] https://en.wikipedia.org/wiki/Logarithmic_scale


I think it starts at .1 at the bottom, but the scan quality makes it difficult to discern the decimal.


Walking is probably the most efficient from a (public) health viewpoint. Given that the major problem in the West is lack of physical activity and excess calorie input.


Which is to say, the least efficient


Well you don't need a bike for walking, so that's gotta count for something (if efficiency is defined as total energy spent per distance)




Consider applying for YC's Fall 2025 batch! Applications are open till Aug 4

Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: