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I hope Sweden and Germany can make a common DIN Deutche industri normen standard for charging electric vehicles on roads. There would be an added benefit if we

by acd 9y ago

I hope Sweden and Germany can make a common DIN Deutche industri normen standard for charging electric vehicles on roads. There would be an added benefit if we could build rail tracks among the electric guidance line. Rail tracks to lower the rolling resistance, metal on metal vs rubber on asphalt. We would then have a hybrid car rail track which should make it easy for autonomous driving. The aim would to bring down the total co2 emissions of transportation. Building both in ground and above ground electrification of cars would be the best system as then cars can charge during good weather conditions and trucks can always charge even during winter time. A system with electric guidance in the ground is a bit vulnerable to snow during winter times. Here is another more rail like track which can be used by trucks but not by cars. https://www.scania.com/group/en/worlds-first-electric-road-opens-in-sweden/ https://www.scania.com/group/en/worlds-first-electric-road-o... Rolling resistance coefficient c of rail c=0.001, dirty tram rails c=0.005, car c=0.02. Ie rails resistance is at least 25 times lower than rubber on asphalt 0.005/0.02. https://en.wikipedia.org/wiki/Rolling_resistance https://en.wikipedia.org/wiki/Rolling_resistance https://www.engineeringtoolbox.com/rolling-friction-resistance-d_1303.html https://www.engineeringtoolbox.com/rolling-friction-resistan...

stefan_ 9y ago
Let's just only have train tracks? We can still have electric trucks for the last mile, but then they won't need electrified roads. Long-distance goods transport with trucks is such a ridiculous concept, it's really time we just face it: it only ever made sense because the state funds the roads and road repair from general taxation, we have ridiculous subsidies for the fossil fuels that make it run and trains had the misfortune to be invented such a long time ago that the government has suffocated the industry. Rolling resistance is somewhat of a rounding error, by the way. The big killer is aerodynamics: the power needed to push air out of the way increases quadratically with speed. But there is a cheat code: if you make the vehicle longer or add something to the back, it can ride in the slipstream. Only you can't make trucks very long at all because they need to work on public roads. Trains on the other hand can be made ridiculously long, saving massively on energy - multiple miles of wagons if you so wish.
- seanmcdirmid 9y ago
  Moving goods from the train to the truck is not a negligible cost. Also, you have to move lots of things in batch with the train, which makes product and supply chains unless nimble. Perishable agriculture products, for one thing, benefit greatly from truck transport.
  - stefan_ 9y ago
    A nimble supply chain, or "just in time" as they call it, is a hack large companies use to shift quantities from one column of their quarterly reports to another that the stock market looks more favourably upon. Analysts can't very well quantify the risk of a JIT supply chain but they know cash flow over finished goods.
    - seanmcdirmid 9y ago
      That isn't true. It means you need less storage space, and you need less capital tied up in parts you aren't using. It also means your cabbages don't rot.
  - thaumasiotes 9y ago
    > Moving goods from the train to the truck is not a negligible cost. Really? I was under the impression that this was one of the primary benefits of standard shipping containers.
    - seanmcdirmid 9y ago
      That goods transfer costs would be negligible?
      - andrewwharton 9y ago
        Between shipping modes, yes. Hence the name "Intermodal Container". https://en.wikipedia.org/wiki/Intermodal_container https://en.wikipedia.org/wiki/Intermodal_container
dest 9y ago
At high velocities (> 40 km/h?) the main drag comes from aerodynamics (turbulence, air viscosity…), not rolling resistance.
- rb808 9y ago
  perhaps with autonomous cars and rails the cars can follow each other very closely so improves aerodynamics too.
  - dest 9y ago
    indeed
  - dx034 9y ago
    They already trialed that with trucks where several trucks form a convoy, controlled from the first one. Saves ~30% fuel for the following trucks. That could be used flexibly and probably contain 5-6 trucks minimum without disturbing traffic.

by acd 9y ago

stefan_ 9y ago

Let's just only have train tracks? We can still have electric trucks for the last mile, but then they won't need electrified roads. Long-distance goods transport with trucks is such a ridiculous concept, it's really time we just face it: it only ever made sense because the state funds the roads and road repair from general taxation, we have ridiculous subsidies for the fossil fuels that make it run and trains had the misfortune to be invented such a long time ago that the government has suffocated the industry. Rolling resistance is somewhat of a rounding error, by the way. The big killer is aerodynamics: the power needed to push air out of the way increases quadratically with speed. But there is a cheat code: if you make the vehicle longer or add something to the back, it can ride in the slipstream. Only you can't make trucks very long at all because they need to work on public roads. Trains on the other hand can be made ridiculously long, saving massively on energy - multiple miles of wagons if you so wish.

seanmcdirmid 9y ago
Moving goods from the train to the truck is not a negligible cost. Also, you have to move lots of things in batch with the train, which makes product and supply chains unless nimble. Perishable agriculture products, for one thing, benefit greatly from truck transport.
- stefan_ 9y ago
  A nimble supply chain, or "just in time" as they call it, is a hack large companies use to shift quantities from one column of their quarterly reports to another that the stock market looks more favourably upon. Analysts can't very well quantify the risk of a JIT supply chain but they know cash flow over finished goods.
  - seanmcdirmid 9y ago
    That isn't true. It means you need less storage space, and you need less capital tied up in parts you aren't using. It also means your cabbages don't rot.
- thaumasiotes 9y ago
  > Moving goods from the train to the truck is not a negligible cost. Really? I was under the impression that this was one of the primary benefits of standard shipping containers.
  - seanmcdirmid 9y ago
    That goods transfer costs would be negligible?
    - andrewwharton 9y ago
      Between shipping modes, yes. Hence the name "Intermodal Container". https://en.wikipedia.org/wiki/Intermodal_container https://en.wikipedia.org/wiki/Intermodal_container

dest 9y ago

At high velocities (> 40 km/h?) the main drag comes from aerodynamics (turbulence, air viscosity…), not rolling resistance.

rb808 9y ago
perhaps with autonomous cars and rails the cars can follow each other very closely so improves aerodynamics too.
- dest 9y ago
  indeed
- dx034 9y ago
  They already trialed that with trucks where several trucks form a convoy, controlled from the first one. Saves ~30% fuel for the following trucks. That could be used flexibly and probably contain 5-6 trucks minimum without disturbing traffic.