(NOTE: The masthead of my blog reads, "... the most efficient form of human transportation ever devised - BICYCLES!" Am I prepared to back that up? Should I elaborate from time to time?)
Late last month, I wrote a little about the Car of the Future, a PBS Nova episode exploring future transportation.
Among other things, the program pointed out that a typical internal-combustion vehicle is extremely inefficient, in converting fuel into transportation energy. (Since much of the power is scrubbed away "between the engine and the rear wheels," and also because most of the remaining power is devoted to moving the vehicle itself, rather than its occupants or payload.)
One of my cycling brothers, bob t, replied, "... I was wondering if any studies had been done regarding the efficiency of a bicycle." He searched and found some info, "Pedal power probe shows bicycles waste little energy." (Click HERE to link.) Engineers at Johns Hopkins University determined that a bicycle is at least 81% efficient, in using energy for transportation. Amazing, particularly when you consider that the standard "safety bicycle" design hasn't changed significantly in almost 130 years. (If anything, it's become more efficient as bicycle weight has dropped significantly in that time.)
Of course, it's difficult to make an objective comparison in transportation efficiency between a car, a bus, a train, a bike rider, etc. How do you measure the amount of energy expended?
A guy - a biology professor named Vance Tucker at Duke University - tried to do just that in a study he conducted a few years back. (He had been studying the amount of energy expended by various bird species while flying, and got the notion of expanding that study.)
He came up with these numbers:
CALORIES PER PERSON, PER MILE OF TRAVEL
Automobile (1 occupant) - 1,860
Transit Bus - 920
Transit Rail - 885
Walking - 100
Bicycling - 35
Tucker's conclusion: "Statistically, the most efficient animal known in the entire universe is a human being on a bicycle."
If somebody has some conflicting or more recent data... BRING IT! I'd feel awful if I were perpetuating lies or myths.