If I read this correctly, the position of the automobile is relative to the weight of the automobile itself, not the weight of the individual person being transported; same for other means of motorized transport. The efficiency of motorized transport would look much worse otherwise. The purpose of the single-occupant automobile is to transport the occupant, not to move heavy chunks of steel. And that is the great beauty of the bicycle - the weight of the machine does not significantly add to the energy cost of moving machine and rider.
I'd vote for two more efficient modes of transport than a man on a bike: * a man on an electric bike * a godwit, which flies for 10,000km on less than a half kilo of body fat.
I watched all 5 of the episodes of Mr. Boal's presentation. One of the things he said was that the chart was misleading because the energy requirement for the bicycle did not include the embeded energy in the road _or_ the bicycle. To be fair, it is biased in favour of the car in the same way. However, it is relevant in comparison to any animal, or to a human being walking. It's easier to walk on a sidewalk, but a person can manage a rough trail on foot much better than on a bicycle.
The New Zealand Advertising Standards Authority agrees. A man on a bicycle is more efficient than an electric trolleybus and you better not claim the opposite
@patty: that's easy, you use a recumbent bike. It is even more efficient than a standard diamond-frame bike (less air drag), and you don't need a helmet -- if a recumbent tilts, you don't hit your head on the pavement.
14 comments:
You forgot the disclaimer: Only applies when cycling on smooth paving
could be an illustration to this, probably my all-time favorite passage on biking: http://clevercycles.com/energy_and_equity/#degofs
If I read this correctly, the position of the automobile is relative to the weight of the automobile itself, not the weight of the individual person being transported; same for other means of motorized transport. The efficiency of motorized transport would look much worse otherwise. The purpose of the single-occupant automobile is to transport the occupant, not to move heavy chunks of steel.
And that is the great beauty of the bicycle - the weight of the machine does not significantly add to the energy cost of moving machine and rider.
It's a great chart - double logarithms and all - because it's such a nice thing to be able to visually compare these abstract numbers.
Merlin, in the light of your statement, how do you like these cars? http://carspector.com/chart/lightest/
Thanks, William - still, none of them beats the bicycle!
I'd vote for two more efficient modes of transport than a man on a bike:
* a man on an electric bike
* a godwit, which flies for 10,000km on less than a half kilo of body fat.
I watched all 5 of the episodes of Mr. Boal's presentation. One of the things he said was that the chart was misleading because the energy requirement for the bicycle did not include the embeded energy in the road _or_ the bicycle. To be fair, it is biased in favour of the car in the same way.
However, it is relevant in comparison to any animal, or to a human being walking. It's easier to walk on a sidewalk, but a person can manage a rough trail on foot much better than on a bicycle.
Glenn
@Matt
This would place the godwit at 0,3;0,7 - squarely between the pigeon and the salmon.
Where would you put a sailboat?
sailboat goes in your garage next to your bicycle, together the most efficient way to travel the globe!
I just thought of something ... how about a salmon on a bicycle?
The New Zealand Advertising Standards Authority agrees. A man on a bicycle is more efficient than an electric trolleybus and you better not claim the opposite
See:
http://wellingtoncycleways.wordpress.com/2010/05/19/go-wellington-trolley-buses-not-as-green-as-a-bicycle/
@JohnCanon - salmon riding bicycles is just silly - how would the salmon wear a helmet?
@patty: that's easy, you use a recumbent bike. It is even more efficient than a standard diamond-frame bike (less air drag), and you don't need a helmet -- if a recumbent tilts, you don't hit your head on the pavement.
Matt is right, a recent energy flow analysis indicated that pedal-assist electric bicycles are the most efficient means of transport yet invented.
http://knol.google.com/k/energy-global-warming-and-electric-bicycles
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