What is the most energy efficient mode of transportation?

Question

Which mode of transportation is the most energy efficient - meaning it requires the least amount of energy to transport people from one place to another?

a) Walking
b) Bicycling
c) Train
d) Car with 5 passengers
e) Moped
f) Horseback riding

Give your answer before reading the Additional Details, which will contain the correct answer. No cheating!

Correct Answer:



B - bicycling is 3 times more efficient than walking, 5 times more efficient than using the train and 15 to 20 times more efficient than driving a car. Cool chart available here:

http://www.exploratorium.edu/cycling/humanpower1.html

ynotfsu1 - good effort, but your equation for Energy is incorrect. Work = Force * Distance would be the most relevant equation, then you need to know how much force each mode of transport takes.

Answer 1

biking is the most effecient for each individual person, the reason being that it uses mechanics of the wheel to use momentum to the advantage rather than jarring of walking. As well, cars only use something like 15% of the energy in fuel to actually propel the car, most is wasted as heat. I bike everywhere, it is great fun and environmentally responisble.

Answer 2

This is actually pretty tough to answer because of many variables.

The formula to be used in this case is mass x velocity x time.

But we also have to take into account the number of people capable of using each mode of transportation. So the solutions that we come up with have to be divided by the number of people that each mode can transport.

We have to assume that the distance is the same for each trip. Let's just say 1 kilometer. We also have to make some assumptions about the mass of some vehicles, the number of people that can ride on a train, and the average speed at which each mode operates.

Hopefully, nobody cares if I use the metric system.

I am going to assume that a person weighs 70 kilos (about 150 pounds).

Walking:
Mass = 70 kilos
Avg speed = 5 kph = 1.4 m / s
Time to travel 1 km = 720 sec

Energy = 70560 units


Bicycling:
Ave mass of a bicycle = 10 kilos (the mass of my bike)
Avg speed of a bicycle = 25 kph = 5.6 m / s
(source: http://en.wikipedia.org/wiki/Bicycle_weight_and_power )
Total mass with rider: 80 kg
Time to travel 1 km = 144 s

Energy = 64512 units


Train:
Avg speed = 200 kph = 56 m/s
Avg mass = 299,000 kg
Passenger total = 309 people (although it is unlikely it will be full)
Added mass from passengers = 21,000 kg
Total mass = 320,000 kg
(source: http://en.wikipedia.org/wiki/Pendolino)
Time to travel 1 km = 18

Energy = 1,044,000 units per person


Car with 5 passengers:
Avg speed of a car = 80 kmh = 22 m / s (total assumption, there are an abundance of possibilities depending on where you are)
Avg mass of a car = 1600 kg
(source: http://www.newrules.org/voice2004/factoids/index.html )
Added mass of passengers = 350 kg
Total mass = 1950 kg
Time to travel 1 km = 45 s

Energy = 390,000 units per person


Moped:
Avg mass =70 kg (assumption)
Avg speed = 40 kph = 11 m / s (assumption)
Total mass with passenger = 140 kg
Time to travel 1 km = 90 s

Energy = 138,600 units


Horseback:
Avg mass = 460 kg
Avg speed = 50 kmh = 14 m / s
(source: http://en.wikipedia.org/wiki/Horse )
Total mass with rider = 530 kg
Time to travel 1 km = 72 s

Energy = 534,240


So the answer is the bicycle.

Cool, I am glad that is over with.

Answer 3

no 1 ,Astral travel ,you take Ahuahuaska and the spirit leaves the body to go traveling ,

Meditation can archieve the same results but you need a lot of experience.
the cheapest form of travel.

No 4 may be walking but the distance is limited and the speed is slow

Horses are very expensive to keep ,unless you have a lot of pasture but again your distance is limited .I know I slept in a barn with my horse for a long time and the thing eats day and night.

Trains go further are quite cheap but they dont cross oceans (Astral travel does)but you can move a lot of people around.

Bicycle is not bad and you get very fit and ocasionally very wet or cold or hot .

Car with 5 friends can be lethal especially if some got beer.(experience)

Moped ties you to the gasoline but is easier than a bike.

Still will come back to Astral travel as the cheapest and furthest , I think you can leave the planet with that and cross dimensions.

A balloon and /or a sailing ship may be the cheapest next ,for cost over distance

I wanted to cheat where are the damn additional details

And Bob is right of course, travel where and why is the essence.you dont use a bike to pick up a ton of bricks.
,and you dont use a tractor to post a letter on the corner.

or take a plane to the pub
hmm,not sure about that one

Way to go green
you understand Astral travel,but Ahuahuaska is more effective than prayers ,so not only angels get to travel you can as well.

Answer 4

Regardless of the correctness of the above observations, I would say that walking is the most energy-efficient mode of transportation, since the bicycle involves manufacturing parts from metals, plastics, rubbers, all of which require a fair amount of energy to produce and create environmental issues.

Answer 5

Your "correct" answer is wrong for the question as stated.

Correct answer is that it depends.

Transporting one person for a short trip - bicycle.

Transporting a family of 5 (including small children) to the movies? The car.

Transporting 20 tons of corn a thousand miles? The train.

Transporting a cowboy 30 miles across rugged terrain? The horse.

Going to the corner to pick up the mail? Walk.

There is no single "correct" answer for many environmental issues. Picking up the right tool for the job is the real key.

Answer 6

I would like to suggest wind power as in sailing ships

it doesn' t require any fossil fuel or human power and can be efficient if time is not a big concern..

Answer 7

That all depends on where you are. I live in North Dakota. A bike is pretty much wothless in January. So is a tiny little "eco car" that will get blown all over the ice like a pop can. I'll go with my big, heavy, 4WD pick-up, thank you.

Answer 8

Why give the correct answer?

I heard cycling was 5 times mpore efficient than walking.

I'm putting together a bike trailer soon, I feel like a big kid!!

Answer 9

One more phisherman. Why not ask for answers to questions you don't know rather than phrasing a statement as a question and phishing for people to agree with your viewpoint? Puts you right up there with the deniers in my book.

Answer 10

I would say the bike is the most efficient means of trans.
also it is very good exercise. lets face it most people are out of shape anyways!! it would doo people good