wajajanJun 28, 2025
kim_harding ✅
"A cyclist can go 3 or 4 times faster than a pedestrian, but uses 5 times less energy. The bicycle is the perfect transducer to match metabolic energy to impedance of locomotion. Equipped with this tool, man outstrips efficiency of not only all machines, but all other animals as well."
—Ivan Illich
Jun 28, 2025 at 4:32pmWeb
Show threadkim_harding ✅Jun 28, 2025
For those asking about the data, the source is, I believe, Transport Policy and the Environment https://www.routledge.com/Transport-Policy-and-the-Environment/Banister/p/book/9780419231400
or maybe one of Professor David Banister's other papers
Transport Policy and the Environment

There is currently considerable concern with limiting the growth of transport demand, the use of resources and related pollution. This book makes a major contribution to the debate on transport and the environment and is likely to become a benchmark against which new research will be developed. Transport Policy and the Environment presents for the first time the results of extensive research: *quantifying the contribution of transport to environmental problems. *assessing the options for resolvi

Routledge & CRC Press
Show threadmatt wilkieJun 28, 2025
@kim_harding thanks for the (likely) data source. What are the text and chart sources? (To anyone)
So far I've found the paragraph requotes going back about 6 years but nothing primary (yet)
Show threadAndreas BurgerJun 28, 2025
@kim_harding diesel and electric rail are not equal...
Show threadkim_harding ✅Jun 28, 2025
@aburgerabz Take it with Professor David Banister https://www.tsu.ox.ac.uk/people/dbanister.html those are his figures, not mine.
Professor David Banister

Show threadReiner Jung 🇬🇱 🇺🇦 🇪🇺Jun 28, 2025

@kim_harding @aburgerabz it seems that his graph is slightly off, but the general picture is right.

Anyway, here is another comparison of busses and trams.
https://bathtrams.uk/the-most-energy-efficient-mode-of-public-transport/

Comparative energy consumption of trams and buses - Bristol & Bath Area Trams Association

For total life cycle comparisions see here: https://bathtrams.uk/relative-life-time-co2-enissions-of-tramways-compared-to-buses-and-busways-taking-into-account-co2-during-construction-ie-steel-and-concrete-etc/ Info from Professor Lewis Lesley: Above: A bombardier tram in the 10th district of Vienna, Austria 2. Alternative calculation. Trams are a seemingly expensive outlay for a city. They require permanent tracks and overhead wires. At least that’s how the figures can often initially appear, but there

Bristol & Bath Area Trams Association -
Show threadZimmieJun 28, 2025
@aburgerabz @kim_harding Last time this came up, I speculated that’s meant to be diesel/electric, as in a diesel generator powering electric motors (how most long-haul routes operate). This is in contrast to light rail or subways, which often use power provided along with the rails themselves (so they don’t have to carry fuel or significant battery capacity).
Show threadviqJun 28, 2025
@bob_zim @aburgerabz @kim_harding this is in Joules. How much energy is necessary to be provided. Regardless of *how* the energy is provided. It doesn't take different amount of energy to move diesel and electric trains.
Show threadmatt wilkieJun 28, 2025
@viq @bob_zim @aburgerabz @kim_harding good point, thank you
Show threadZimmieJun 28, 2025
@viq @aburgerabz @kim_harding Right, but fully-electric trains almost all get the power from outside (which is on the chart as light rail). Batteries big enough to get useful range would be prohibitively heavy, drastically reducing efficiency.
Show threadAndreas BurgerJun 28, 2025
@bob_zim @viq @kim_harding light rail is completely different. who would call trains on the transsib light rail?
Show threadAndreas BurgerJun 28, 2025
@viq @bob_zim @kim_harding as electric motors are much more efficient, this is not true
Show threadAndreas BurgerJun 28, 2025
@bob_zim @kim_harding may be gru in nirth America, but everywhere else, electric is common
Show threadJohn RobinsonJun 28, 2025
@kim_harding Unfortunately we have cars.
Show threadkim_harding ✅Jun 28, 2025

@johnelalamo Time we got rid of them, if we want a liveable planet...

I know some people don't like to face reality, but they can't break the laws of physics with wishful thinking, not matter how much neoclassical school economic likes to pretend otherwise...

Show threadJohn RobinsonJun 28, 2025
@kim_harding Not sure how politically popular it would be though. No, not true, I do know how unpopular it would be!
Show threadhexJun 28, 2025
@johnelalamo @kim_harding it doesn't matter how politically popular it will be. We're getting rid of cars one way or another. Either we're going to choose to get rid of cars on our terms, or we're going to let them collapse society so they can't be supported anymore. You don't get to choose "cars or no cars." You only get to choose "complex society without cars, or no society at all."
Show threadBernd HerdJun 28, 2025
@kim_harding I wonder if the high efficiency of the bicycle compared to walking would be reduced when including the energy to maintain a paved road for cycling with an unpaved track for walking?
Show threadkim_harding ✅Jun 28, 2025
@herdsoft that would be trying to compare apples with oranges, walking on a paved surface is easier than an unpaved surface, the same is true of cycling
Show threadseachangedJun 28, 2025

@herdsoft @kim_harding

This is the comment I was looking for.

Walking can happen anywhere.

Bicycling and motorbikes are presumed to occur on well-trafficed footpaths at the very least.

Cars and taxis and busses and trucks move on roads, without exception.

Trains move on one or more rails.

The megajoules per passenger mile measure is incomplete without the energy costs of building the supporting medium. Biking and walking turn out even better after you count in these full costs.

Show threadBernd HerdJun 29, 2025

@seachanged @kim_harding I recently heard that just sealing a m² of natural land causes about 34 kg CO2 / m² just for sealing.

1000 Cyclists per day using a 2 meter wide cycle way for one kilometer would thus cause 2 * 1000 * 34 = 68000 kg CO2 / Year.

Or 0,2 kg CO2 per kilometer cycled.

That would be 0,75 ton of CO2 for me cycling 4000 km per year? A significant contribution.

Value is from this scientific video:
https://youtu.be/k4DHFk3ccgY?feature=shared&t=365

Prof. Dr. Karsten Tichelmann, TU Darmstadt: Wohnraum ohne Bauland.

YouTube
Show threadWanjaJun 28, 2025
@kim_harding Tandem and recumbent bike nerds in the comments like "not quite perfect, we can go lower 😈"
Show threadkim_harding ✅Jun 28, 2025

@muvlon Yeah, everyone should really be riding a M5 Carbon High Racer... 😉 😂

http://www.m5-ligfietsen.nl/site/EN/Models/Carbon_High_Racer/

M5 Recumbents » Models » Carbon High Racer

M5 Recumbents: development and sales of a broad spectrum of recumbents.

Show threadBen AvelingJun 28, 2025
@kim_harding Rating trucks by passenger kilometers travelled seems unfair.
Show threadMatthew DockreyJun 28, 2025
@kim_harding I love that phrasing so much
Show threadSvavar the NeurospicyJun 28, 2025

I'm quite surprised that the difference between rail and flying isn't greater.

I know there are other factors that make rail travel better for the environment, but that rail is less than 50% more energy efficient than flying is a surprise.

@kim_harding

Show threadOrrock LXXXVI XLVIIJun 28, 2025
@kim_harding This is per passenger mile traveled. I’m surprised jets are less efficient than cars, as they can carry so many more people. Thoughts?
Show threadMegatronicThronBanksJun 28, 2025
@kim_harding But they generate 30 times as much rage in all other road users
Show threadFred MoyerJun 29, 2025
@kim_harding stay away from my burritos
Show threadSueDiOhJun 29, 2025
@kim_harding Factor in distance and let's see how this comes out. 😉
Show threadzipJun 29, 2025
@SueDiOh that's the "per passenger kilometre" part
Show threadSueDiOhJun 29, 2025
@zip Got it. But if I've got to get groceries, and it's always more than 1 bag, and my nearest store is about 7 miles away, the bike is not more efficient. These kinds of comparisons really only work for cities, is all I'm saying.
Show threadzipJun 29, 2025
@SueDiOh looking at the numbers on the graph I'd say you'd have to make 35 trips on the bike before you've used more energy than one car trip... but yes, these numbers don't account well for practicality considering that's an hour round trip on the bike
Show threadSueDiOhJun 29, 2025
@zip And it assumes ideal biking conditions.
I'm not here to pick a fight. I'm just here to remind people that you can make a statistic to support any argument.
Show threadMrEdgarBassJun 29, 2025
@kim_harding How is a car different from a taxi? I presume an idle taxi does not have the engine running.
Show threadmfriedenhagenJun 29, 2025
@kim_harding Most of the time I am a pedestrian because my work is only 2km away and I like to walk this distance. Twice per week I take my bike and it feels like magic how fast and effortless I chuck through kilometers.
Show threadAriobarzanJun 29, 2025
@kim_harding We should double the cost of vehicles because of traffic!
Show threadDarcyJun 30, 2025

@kim_harding

I get this but I have a question.

Which is more efficient, single parcels being delivered to individual doors, or a 53' semi delivering hundreds of items to a store?

Show threadSarah Peper 🏳️‍⚧️🇺🇦Jun 30, 2025

@kim_harding I'm surprised by the large gap between cars and taxis.

Also by the choice of a 727 for plane. It was already quite outdated in 1999

Show threadSarah Peper 🏳️‍⚧️🇺🇦Jun 30, 2025
@kim_harding (but then again, I also fundamentally disagree with grouping all heavy rail with the London Underground. Or even grouping the London Underground with itself)
Show threadDerek MartinJul 1, 2025
@kim_harding @mhoye That’s precisely why Steve Jobs called the computer a bicycle for the mind.