3 ms·

But mass transit carries more people per wheel, and the weight of the bus does not scale linearly with the carrying capacity, so it doesn't automatically follow

But mass transit carries more people per wheel, and the weight of the bus does not scale linearly with the carrying capacity, so it doesn't automatically follow that "individual transportation is actually better...". I doubt that 50 EVs carrying one person each generate less tyre wear than one bus carrying 50 people.

XorNot 2y ago
Road damage is a function of the power of 4[1] generally. A BYD bus weighs 18 tons and carries 32 people including the driver. [2] A BYD Atto 3[3] carries upto 5 people and weighs 1.8 tons unloaded. The proportional road wear function of the BYD Atto would be about 10 (1.8^4). For the bus it would be (18^4) 104,976. So the bus is 10,000 times more wear then the car. Per passenger it's 3000 wear units for the bus versus ~10 for the car. [1] https://en.m.wikipedia.org/wiki/Fourth_power_law https://en.m.wikipedia.org/wiki/Fourth_power_law [2] https://en.m.wikipedia.org/wiki/BYD_K_series https://en.m.wikipedia.org/wiki/BYD_K_series [3] https://ev-database.org/car/1782/BYD-ATTO-3 https://ev-database.org/car/1782/BYD-ATTO-3
- LargoLasskhyfv 2y ago
  Roads are for walking, bicycling and repair/cleaning/utility/emergency services. Deliveries go by subterran pallet-delvicery networks, to be last-miled by freight-cycles. Mass-transit by rails. Long-transit by maglev or air. Fuck cars!
  - greenavocado 2y ago
    This only works where the population has a very high average IQ (ability to understand second and third order effects of long expensive projects), no anti-social behavior (no corruption or theft in public works projects), with politicians whose interests align with the people. Unfortunately we live in a world where you will be stabbed to death and robbed for walking down the sidewalk holding a $20 bill openly in your hand.
    - LargoLasskhyfv 2y ago
      There are regional differences to that sort of behaviour.
- adrianN 2y ago
  The average car carries 1.2 people, how many does the average bus carry?
  - XorNot 2y ago
    The 10 number is for literally one person, I'm also discounting their mass (this isn't a precision exercise). If you add 5 people to the car, call it 80kg per person so your you goto about 2.2 tons, then the damage number would be about ~24, but divided by 5 you end up with 4.8 (so a fully loaded car does about half the damage per person compared to one with a single occupant). The thing is of course on some level this is large scaling factors applied to small numbers - i.e. tires still don't fail that quickly anyway, neither do roads. Conversely it is actually weird to see that on this one metric, numerous self driving EV taxis is actually better.
- Qwertious 2y ago
  >Road damage is a function of the power of 4[1] generally. Per axle. So for instance, if you're comparing an 18-wheeler to a 4-wheel car you have to compare (truck-weight/9)^4 to (car-weight/2)^4. Or ((truck-weight/9)/)car-weight/2))^4 So if a bus was an 18-wheeler, it would be about 16x the wear units, /32 passengers brings it to half. It doesn't make a difference for the bus you linked, since it's also a 4-wheeler like cars, but if we cared we could add more axles to buses. But, why don't we do that already? Apparently... 1) regulations don't require it 2) we sort of already do; some buses have rear wheel bogies that have 4 wheels of which 2 are kept raised at lighter weights. Which is basically all the time because regulations don't require it. 3) more wheels reduces fuel efficiency (and costs more money), obviously 4) wheels take up space and reduce passenger capacity, which make the bus less efficient if you don't care about road wear 5) buses have a much more consistent weight load than trucks, since ~30 passengers would be only 3 tonnes of difference. I'm wildly out of my depth on buses/trucks here, so if a mechanic could chime in on bus/truck weight distribution and wheels that'd be great.
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XorNot 2y ago

Road damage is a function of the power of 4[1] generally. A BYD bus weighs 18 tons and carries 32 people including the driver. [2] A BYD Atto 3[3] carries upto 5 people and weighs 1.8 tons unloaded. The proportional road wear function of the BYD Atto would be about 10 (1.8^4). For the bus it would be (18^4) 104,976. So the bus is 10,000 times more wear then the car. Per passenger it's 3000 wear units for the bus versus ~10 for the car. [1] https://en.m.wikipedia.org/wiki/Fourth_power_law https://en.m.wikipedia.org/wiki/Fourth_power_law [2] https://en.m.wikipedia.org/wiki/BYD_K_series https://en.m.wikipedia.org/wiki/BYD_K_series [3] https://ev-database.org/car/1782/BYD-ATTO-3 https://ev-database.org/car/1782/BYD-ATTO-3

LargoLasskhyfv 2y ago
Roads are for walking, bicycling and repair/cleaning/utility/emergency services. Deliveries go by subterran pallet-delvicery networks, to be last-miled by freight-cycles. Mass-transit by rails. Long-transit by maglev or air. Fuck cars!
- greenavocado 2y ago
  This only works where the population has a very high average IQ (ability to understand second and third order effects of long expensive projects), no anti-social behavior (no corruption or theft in public works projects), with politicians whose interests align with the people. Unfortunately we live in a world where you will be stabbed to death and robbed for walking down the sidewalk holding a $20 bill openly in your hand.
  - LargoLasskhyfv 2y ago
    There are regional differences to that sort of behaviour.
adrianN 2y ago
The average car carries 1.2 people, how many does the average bus carry?
- XorNot 2y ago
  The 10 number is for literally one person, I'm also discounting their mass (this isn't a precision exercise). If you add 5 people to the car, call it 80kg per person so your you goto about 2.2 tons, then the damage number would be about ~24, but divided by 5 you end up with 4.8 (so a fully loaded car does about half the damage per person compared to one with a single occupant). The thing is of course on some level this is large scaling factors applied to small numbers - i.e. tires still don't fail that quickly anyway, neither do roads. Conversely it is actually weird to see that on this one metric, numerous self driving EV taxis is actually better.
Qwertious 2y ago
>Road damage is a function of the power of 4[1] generally. Per axle. So for instance, if you're comparing an 18-wheeler to a 4-wheel car you have to compare (truck-weight/9)^4 to (car-weight/2)^4. Or ((truck-weight/9)/)car-weight/2))^4 So if a bus was an 18-wheeler, it would be about 16x the wear units, /32 passengers brings it to half. It doesn't make a difference for the bus you linked, since it's also a 4-wheeler like cars, but if we cared we could add more axles to buses. But, why don't we do that already? Apparently... 1) regulations don't require it 2) we sort of already do; some buses have rear wheel bogies that have 4 wheels of which 2 are kept raised at lighter weights. Which is basically all the time because regulations don't require it. 3) more wheels reduces fuel efficiency (and costs more money), obviously 4) wheels take up space and reduce passenger capacity, which make the bus less efficient if you don't care about road wear 5) buses have a much more consistent weight load than trucks, since ~30 passengers would be only 3 tonnes of difference. I'm wildly out of my depth on buses/trucks here, so if a mechanic could chime in on bus/truck weight distribution and wheels that'd be great.
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