this post was submitted on 21 Apr 2026
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Today I Learned

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https://en.wikipedia.org/wiki/Energy_efficiency_in_transport

that table is thoroughly fascinating. i mean all of them, there's more than one table on that article

apparently walking is the most energy-efficient transport mode of all?!?!? apart from bicycles

what i find mind-blowing is that airplanes consume approximately the same amount of energy as cars and trains. I mean i can easily see cars and trains being on the same level, but i always thought that airplanes consumed like an order of magnitude more fuel than cars. considering how everybody keeps saying that "airplanes consume so much fuel" and such. crazy.

and also boats are less efficient than i thought? boats consume 16 L/100 km while cars, trains and airplanes consume 6 L/100 km?

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[–] helvetpuli@sopuli.xyz 2 points 3 hours ago

Why are those passenger numbers for the train so low? Here at least the railway moves something like 2000 passengers per vehicle on average. Over 3000 at peak times.

[–] Jiral@lemmy.org 15 points 17 hours ago* (last edited 17 hours ago)

This table is heavily biased against transit. First of all it is based on data from places that have by far and large underinvested inefficient underused transit in cities built for cars and not for transit. Secondly MJ/passenger/ distance is itself heavily biased against transit. Distance travelled is of no value in itself. Getting to places of interest is of value. Transit journies are on aversge shorter because transit oriented corridors allow for more compact urban layouts. Having to drive twice as far because cars need so much space, adds no value to going to the super market.

[–] quick_snail@feddit.nl 12 points 18 hours ago (1 children)

This is misleading.

Airplanes are worse not because of energy consumption per person, but because of carbon equivalent units are magnitudes higher when nitrogen oxides are burned at a high altitude.

[–] Trainguyrom@reddthat.com 10 points 18 hours ago (2 children)

Also average load of the bus being only ~8 people? Like yeah that seems about right when I've ridden the shitty bus before but that's a number that can really be improved upon

[–] dogdeanafternoon@lemmy.ca 2 points 4 hours ago

That’s high for my area. 3-4 is probably closer to average

[–] quick_snail@feddit.nl 5 points 18 hours ago

Sadly it's missing bicycles and Falkor

[–] SlurpingPus@lemmy.world 57 points 1 day ago* (last edited 1 day ago) (5 children)

Buses seem to be shafted in that comparison by the fact that no one uses them in the US. Where I am, a bus gets just seven passengers only in the middle of the night. At other times, buses would be easily at the top of the table if not for the fact that our trains also move more than twenty people per car.

[–] acockworkorange@mander.xyz 26 points 1 day ago (2 children)

That's because mass transit is, with very few exceptions, absolutely ass in the USA. People only use it as the absolute last resort. That skews the table a lot against any public transit.

[–] quick_snail@feddit.nl 3 points 18 hours ago (2 children)

Easy problem to solve.

Increase the cost of gas to $100 per liter for consumers (exceptions for food delivery, etc) and use the surplus income to build better busses.

Boom. Everyone has excellent public transportation. And everyone uses it.

[–] acockworkorange@mander.xyz 7 points 17 hours ago

Your assumption that busses exist so they can be improved is quite telling. Huge swaths of the population, even living in million inhabitants+ cities, simply are not served by any form of mass transit.

The reason public transit works so well in Germany (where I did live for a bit) and Holland (visited and read about) is not because taking a car is more expensive. It's because mass transit works well, it's there when you need it, gets you to your destination in reasonable time and comfort, and is easy to use.

The very urban fabric in the USA is car oriented. Every little bodega has to have a dozen parking spaces built by law. Supermarkets have 3 to 4 times their store area wasted in parking lots. Everything is far apart because of this, so walking is impractical. With everyone driving to places, you need wide, fast roads, which makes biking places very unsafe. Every once in a while I see a white painted bike attached to a memorial in a light post, commemorating a life lost. And I live in the suburbs.

It's not an insurmountable problem, the Netherlands did that in the 70s. But any solution that proposes a simple fix is doomed to failure. This has to be a concerted, intense effort to work.

[–] Trainguyrom@reddthat.com 3 points 18 hours ago (1 children)

My approach would be to jack up vehicle registration fees. Simply doubling the vehicle registration cost every year over about 5 years would make individual car ownership expensive enough that people will really try to avoid it.

By the fifth year you're looking at about $5k per year just to legally own and operate a car on public roads, which is workable (most people pay more than that per year for their car loans) but it's more than enough to make any family think twice about owning more than one car, and more than enough to make not owning a car and just renting/taking public transit a super attractive option. Plus it's more than the cost of a mid-range e-bike so trading your car for an ebike becomes extremely cost effective with a break-even point measured in just months

5 years is also enough time to get roads reconfigured for the new traffic flow of mostly ebikes, get more buses in the roads and start planning/building out new train routes. There's an incredible rail network still in the US and just putting out more passenger services on the existing tracks that are presently freight-exclusive would make a massive difference

[–] quick_snail@feddit.nl 2 points 6 hours ago

Two stroke engines in lawn care motors produce worse pollution than cars.

We need to increase the cost of gas. It's not just cars.

[–] SlurpingPus@lemmy.world 8 points 1 day ago (10 children)

That always sounded to me like a chicken-egg problem. People don't use buses and subways, because buses and subways are populated by weird dirty hobos. Well guess what...

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[–] AA5B@lemmy.world 12 points 1 day ago* (last edited 1 day ago) (8 children)

Maybe it’s the same for commuter rail. It’s weird seeing average 33 passengers, when they were always standing room only while I was riding

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[–] birdwing@lemmy.blahaj.zone 6 points 1 day ago

Urban sprawl, zoning laws, lack of dedicated bus lanes with safe and walkable stops, low frequency, comfort (seat, space, aircon/heat, chargers), and prices.

Comfort and frequency are the easiest to solve, prices, urban sprawl, zoning laws, and the like less so. Not to mention that labour rights must be improved for bus drivers.

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[–] f314@lemmy.world 78 points 2 days ago* (last edited 2 days ago) (4 children)

For modes using electricity, losses during generation and distribution are included.

They should do this for the fossil fuel modes as well and see what that does to the numbers!

[–] quick_snail@feddit.nl 4 points 18 hours ago

They should also add the cost of harm done to the environment. Then it would be close to infinitely.

[–] davidagain@lemmy.world 6 points 1 day ago (1 children)

Yeah for the diesel/petrol/gasoline ones they've excluded energy wastage at the extraction point (eg if they have a flare), moving the oil to the oil refinery (from wherever in the world it came from), during the refining process (definitely a lot of energy used there), transporting the end product to wherever the filling station is, and finally pumping it into the vehicle.

But they included all the comparable costs for electricity. They wanted fossil fuels to look as good as possible. I'm extremely skeptical about data that suggests air travel is efficient when people have been talking for years about how wasteful and environmentally damaging it is.

[–] hraegsvelmir@ani.social 1 points 3 hours ago

For long travel, like intercontinental level distances, it probably is pretty efficient with a full plane. I've always understood that the waste and environmental damages are more from a combination of the use of private planes, and short routes that really ought to be train trips with the infrastructure to make them a preferable option to flying.

For example, if I suddenly found out that I needed to get from NYC to Boston by midnight tonight, without using a car, it should be a no-brainer to take Amtrak up there. Yet, even with fuel costs for airlines being quite high right now, there are exactly 4 trains leaving Penn Station for Boston that are cheaper than just catching a flight from JFK, and in the best of cases, they take about 4 times as long to cover that distance. It should really be significantly cheaper than flying in order to deter the majority, if not all of those people who do not expressly need to make that trip in just over an hour, for whatever reason, from taking those sorts of flights. Cheap enough that flying simply isn't price competitive, and that people don't mind the extra travel time.

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[–] vivalapivo@lemmy.today 24 points 2 days ago (1 children)

what i find mind-blowing is that airplanes consume approximately the same amount of energy as cars

The same logic could be applied to spacecrafts. The energy efficiency of a spacecraft travelling to Mars is approximately 10-50MJ/100km - between a car and a bicycle. Should everyone take a ticket to Mars rather than driving their SUV to work?

[–] testaccount372920@piefed.zip 17 points 2 days ago (1 children)

Planes and trains are also quite close to each other and in many cases cover the same routes. However, planes run 100% on fossil fuels, trains are often electric.

[–] SCmSTR@lemmy.blahaj.zone 11 points 2 days ago (2 children)

...What's keeping us from having electric planes?

[–] Nighed@feddit.uk 30 points 2 days ago (4 children)

Weight. As you burn down fuel, the plane gets lighter, so requires less fuel/energy for the remaining distance.

With a battery powered plane, the battery is just as heavy all the time. It also has less energy density. This means wayyy less range with current tech.

[–] MurrayL@lemmy.world 30 points 2 days ago (7 children)

Clearly the solution is lots of little batteries, so the plane can drop them as it flies.

[–] AstralPath@lemmy.ca 13 points 1 day ago

Into the ocean, ideally. That way we spur growth in our mining sector to replace them all with new batteries every time. The shareholders are going to love us.

[–] otter@lemmy.ca 4 points 1 day ago* (last edited 1 day ago)

This might actually work? I imagine getting up to altitude is the most difficult and energy intensive step since the engines are operating at a higher power and the air is thicker.

Even if that's only 10% or 15% of the overall energy usage, being able to drop the battery and have it return to the airport on its own for reuse could be a cool concept. You could also optimize that particular battery for take off & climbing, and have the main battery for cruising.

It just needs to be able to pilot itself back to a landing / catching structure 😄

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[–] testaccount372920@piefed.zip 3 points 1 day ago (1 children)

Technology, or rather, lack thereof. As others pointed out, planes need to bring their own energy supply and use additional energy for that. Weight is a very big factor for air transport's energy consumption. Fossil fuels have a very high energy density, which make them great for bringing along. Once light weight battery tech (without excessively large sizes) becomes available, it should be no issue to electrify planes. Alternatively, find another source of electricity. E.g. nuclear has a much higher energy density than fossil, but obviously has it's own issues, as do all other currently available tech options.

[–] Trainguyrom@reddthat.com 2 points 17 hours ago

Weight is a very big factor for air transport’s energy consumption. Fossil fuels have a very high energy density, which make them great for bringing along.

Fossil fuels also have the benefit of being weight that's shed (burned) as you fly, so an international flight will be much lighter when landing than it weighs when taking off. It's like the rocket equation but much less severe due to much less energy requirement

[–] FishFace@piefed.social 12 points 2 days ago (1 children)

Our World in Data has more useful figures that attempt to be comparable. In short, it very strongly contradicts that table.

[–] Alberat@lemmy.world 7 points 1 day ago (2 children)
[–] vatlark@lemmy.world 1 points 5 hours ago (1 children)

I didn't expect that a train would be more efficient than biking. I guess the efficiencies of scale are hard to beat, but still.

I'm tempted to think the minimal biking infrastructure would help bikes, but infrastructure amortises nicely so probably not.

[–] Alberat@lemmy.world 2 points 5 hours ago

yeah idk if infrastructure is accounted for here... also maybe if youre vegetarian or something biking is more efficient

[–] Dyf_Tfh@piefed.zip 8 points 1 day ago

Airplane got a huge correction because emissions at high altitude is worse for the climate.

This part is a fairly new consensus, at some point air travel was even maybe beneficial for the climate due to formation of cloud cover.

Energy efficiency is not equivalent to CO2 emissions.

[–] cornshark@lemmy.world 11 points 2 days ago (2 children)
[–] Trainguyrom@reddthat.com 3 points 17 hours ago* (last edited 17 hours ago)

It's a bonkers newish form of not-a-bus, often running passenger vans, usually operates where you either book your rides a day or two in advance or book with an app and wait 5-120 minutes for it to show up, and the service runs door to door.

They're ultimately super inefficient in the real world requiring an extremely high driver:passenger ratio to be at all competitive with bus services

Edit to add: it's basically the answer to "what if taxi replace bus?"

[–] gasgiant@lemmy.ml 11 points 2 days ago

My guess is taxis and things like Uber.

Something you have to call up/book to get anywhere

I’ve always thought that a 60 passenger bus with 2 people on it is never going to be as efficient as a car with 2 people. Probably closer to 2 cars with 1 each. And that’s a strikingly common situation in North America because they won’t buy a smaller bus and electric busses are still a dangerous concept for so many transit managers.

[–] AA5B@lemmy.world 5 points 1 day ago
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