Re:Electric vehicles are way more energy-efficient than inte...
by hot_gril on Sunday August 14, 2022 @03:35AM
(#32457270)
I'd expect the train to be more efficient than the bike in terms of (load mass) * (distance traveled) / (energy used). Proportional to the size of the load, you lose a lot of energy to air resistance on a bike. Trains only push the air out of the way once on the front, and they're long, plus there's less friction from the wheels.
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Re:Electric vehicles are way more energy-efficient than inte...
by occz on Sunday August 14, 2022 @03:48AM
(#32457335)
Looks like trains will beat out bicycles in some cases, but they lose out to e-bikes and e-scooters. Check the table in this helpful article: https://en.wikipedia.org/wiki/Energy_efficiency_in_transport
Re:Electric vehicles are way more energy-efficient than inte...
by Xylakant on Sunday August 14, 2022 @04:20AM
(#32457486)
I’m certain we’re missing something in that article. An electric bike shouldn’t be more efficient than a normal bike - it’s heavier and the wind resistance is the same. My first guess is that the power use for the electric assist only considers the electric assist, not the human riders portion.
Re:Electric vehicles are way more energy-efficient than inte...
by endless1234 on Sunday August 14, 2022 @05:03AM
(#32457699)
Humans are quite inefficient - we can convert around 25% of food energy to work. The losses in the power plant generating the electricity for charging the e-bike's battery and the motor's efficiency losses would result in a higher overall efficiency than 25%.
Re:Electric vehicles are way more energy-efficient than inte...
by makapuf on Sunday August 14, 2022 @06:29AM
(#32458111)
People generally dont need more calories that they already have, they need less. They must do (but dont do enough) physical exercice to loose extra energy they consume (in places where cars are an issue).
Re:Electric vehicles are way more energy-efficient than inte...
by endless1234 on Sunday August 14, 2022 @06:54AM
(#32458230)
Sure, but that doesn't really play into the equation when comparing the pure efficiency of different transportation methods. Of course in practice since it's good to exercise at least 30min daily, you can think of the energy spent during that as free from a efficiency standpoint
Re:Electric vehicles are way more energy-efficient than inte...
by Izkata on Sunday August 14, 2022 @04:41AM
(#32457598)
Heavier would seem like a benefit to me, wouldn't inertia improve its score over longer distances?
Re:Electric vehicles are way more energy-efficient than inte...
by Xylakant on Sunday August 14, 2022 @04:48AM
(#32457626)
No, the only things that matter are the losses and those are due to air resistance (same), rolling resistance (increases linear with weight) and losses due to braking/acceleration (grows quadratic with weight). Heavier is always worse. Note that electric bikes usually don’t even have recuperative braking due to the complexities involved.
If heavier were better, we’d see all Tour de France riders use cast iron wheels and frames ;)
Re:Electric vehicles are way more energy-efficient than inte...
by hot_gril on Monday August 15, 2022 @04:39PM
(#32475056)
You might be thinking of heavier race cars with bigger engines generally having higher top speeds. They aren't more efficient, just more powerful, and weight doesn't affect top speed (only acceleration).
Re:Electric vehicles are way more energy-efficient than inte...
by Xylakant on Sunday August 14, 2022 @04:22AM
(#32457499)
Trains travel much faster and air resistance scales quadratic. But otoh, being able to travel at faster speeds obviously is a major advantage for a train. Now, if we could just combine the two and have enough bike slots on a train, that would be amazing.