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Trains are large and inflexible. Short of having a city-block resolution freight train network at every population center, you'll need something flexible for t

Trains are large and inflexible. Short of having a city-block resolution freight train network at every population center, you'll need something flexible for the last mile of delivery.

ashtonkem 7y ago
You’re misunderstanding. The only reason why you’d need on-road recharging for hypothetical autonomous semi trucks is if they’re regularly traveling outside the range of their batteries, which is probably in the 400-500mi range. In a well designed infrastructure system, that shouldn’t happen often. Instead the hops of hundreds of miles should be handled by trains, leaving semi trucks for the last dozens of miles from train hub to area of need. Some long haul trucking will happen, but it should be a slim minority of cases.
- dsfyu404ed 7y ago
  Adding an extra step (rail hub to short haul truck transition, potentially at both ends of the trip) adds cost. This cost is (and will be for the foreseeable future) less than having the less efficient semi-truck do the entire trip at least for the kinds of loads that are currently carried by semi-truck. JIT inventory systems also don't play nice with rail.
  - ashtonkem 7y ago
    Semi trucks are cheaper because they receive a $125B+ yearly subsidy in the form of road maintenance. Semi trucks do 99% of the damage to our public roads, but only pay 35% of the cost. I suspect that rail would be much more price competitive if we took that subsidy away. You’re right about JIT, but we’re also seeing the downsides of JIT infrastructure during this pandemic. I suspect that we’ll see a push for more redundancy in our supply chain for reasons completely unrelated to trucks vs. trains.
    - slavik81 7y ago
      Assuming we're resurfacing our roads once every 5 years, if we banned trucks it would take 100x longer to accumulate the same amount of damage, so we'd be able to resurface only once every 500 years? I would expect there to be a significant amount of damage done just by the elements, independent of usage.
      - ashtonkem 7y ago
        There’s also the fact that roads are built up to trucking standards. Without trucks the roads would be thinner, reducing cost and pollution (concrete is a major source of CO2).
        throwaway0a5e 7y ago
        Roads are mostly made from asphalt and mother nature would still destroy them in well under 100yr in most places.
        ashtonkem 7y ago
        Highways are much more relevant when we’re talking about trucking, and highways are largely concrete.
        throwaway0a5e 7y ago
        This is utterly false and in a trivially verifiable way in this age of street view. Raised highways sometimes have concrete decks because the strength can be attractive but the overwhelming majority of highways are asphalt. At or below grade highways are almost always asphalt. Tunnels are often concrete but those are a vanishingly small minority of miles.
        ashtonkem 7y ago
        If you’re going to call something “utterly and trivially verifiable (sic) false” you should actually check. Interstate highways use more cement than asphalt. “The analysis shows that a total of approximately 1.5 billion metric tons (Gt) of aggregates, 35 million metric tons (Mt) of asphalt, 48 Mt of cement, and 6 Mt of steel is in place in interstate highways.” https://pubs.usgs.gov/fs/2006/3127/2006-3127.pdf https://pubs.usgs.gov/fs/2006/3127/2006-3127.pdf
- jayd16 7y ago
  You might still want want "in flight" charging even for shorter trips just to keep trucks moving but I guess the world where load/unload times aren't enough is pretty unrealistic.
ramshorns 7y ago
The inflexibility of trains can be a feature in some cases. People like to live near subway and commuter rail stations partly because they know the route and service level are much less likely to abruptly change on them than a bus route would.
- ashtonkem 7y ago
  They’re also more immune to congestion. Back when I lived in Chicago and used public transit, one would strongly prefer the rail over buses when possible, except in cases where the bus was an express route.

Trains are large and inflexible. Short of having a city-block resolution freight train network at every population center, you'll need something flexible for the last mile of delivery.

ashtonkem 7y ago

You’re misunderstanding. The only reason why you’d need on-road recharging for hypothetical autonomous semi trucks is if they’re regularly traveling outside the range of their batteries, which is probably in the 400-500mi range. In a well designed infrastructure system, that shouldn’t happen often. Instead the hops of hundreds of miles should be handled by trains, leaving semi trucks for the last dozens of miles from train hub to area of need. Some long haul trucking will happen, but it should be a slim minority of cases.

dsfyu404ed 7y ago
Adding an extra step (rail hub to short haul truck transition, potentially at both ends of the trip) adds cost. This cost is (and will be for the foreseeable future) less than having the less efficient semi-truck do the entire trip at least for the kinds of loads that are currently carried by semi-truck. JIT inventory systems also don't play nice with rail.
- ashtonkem 7y ago
  Semi trucks are cheaper because they receive a $125B+ yearly subsidy in the form of road maintenance. Semi trucks do 99% of the damage to our public roads, but only pay 35% of the cost. I suspect that rail would be much more price competitive if we took that subsidy away. You’re right about JIT, but we’re also seeing the downsides of JIT infrastructure during this pandemic. I suspect that we’ll see a push for more redundancy in our supply chain for reasons completely unrelated to trucks vs. trains.
  - slavik81 7y ago
    Assuming we're resurfacing our roads once every 5 years, if we banned trucks it would take 100x longer to accumulate the same amount of damage, so we'd be able to resurface only once every 500 years? I would expect there to be a significant amount of damage done just by the elements, independent of usage.
    - ashtonkem 7y ago
      There’s also the fact that roads are built up to trucking standards. Without trucks the roads would be thinner, reducing cost and pollution (concrete is a major source of CO2).
      - throwaway0a5e 7y ago
        Roads are mostly made from asphalt and mother nature would still destroy them in well under 100yr in most places.
        ashtonkem 7y ago
        Highways are much more relevant when we’re talking about trucking, and highways are largely concrete.
        throwaway0a5e 7y ago
        This is utterly false and in a trivially verifiable way in this age of street view. Raised highways sometimes have concrete decks because the strength can be attractive but the overwhelming majority of highways are asphalt. At or below grade highways are almost always asphalt. Tunnels are often concrete but those are a vanishingly small minority of miles.
        ashtonkem 7y ago
        If you’re going to call something “utterly and trivially verifiable (sic) false” you should actually check. Interstate highways use more cement than asphalt. “The analysis shows that a total of approximately 1.5 billion metric tons (Gt) of aggregates, 35 million metric tons (Mt) of asphalt, 48 Mt of cement, and 6 Mt of steel is in place in interstate highways.” https://pubs.usgs.gov/fs/2006/3127/2006-3127.pdf https://pubs.usgs.gov/fs/2006/3127/2006-3127.pdf
jayd16 7y ago
You might still want want "in flight" charging even for shorter trips just to keep trucks moving but I guess the world where load/unload times aren't enough is pretty unrealistic.

ramshorns 7y ago

The inflexibility of trains can be a feature in some cases. People like to live near subway and commuter rail stations partly because they know the route and service level are much less likely to abruptly change on them than a bus route would.

ashtonkem 7y ago
They’re also more immune to congestion. Back when I lived in Chicago and used public transit, one would strongly prefer the rail over buses when possible, except in cases where the bus was an express route.