Usually, the bicycle wins.
Bike are an extremely energy-efficient form of transportation. As the graph above shows, riding a bicycle is more than twice as efficient than walking. This is in terms of megajoules of energy expended per kilometer traveled.
The bike comes ahead of every other common transportation choice, including public transport and personal cars.
Some people object to the comparison of biking (and walking) to things like a taxi or a private car because human-powered transport does require calories to make it go. And those calories - i.e. food - may be less efficient to create than say, diesel fuel. Which means that the caloric cost of bicycle commuting for your daily transport may actually cost you more than the gas for your car.
In addition, to get these figures, the different modes that can carry more passengers were weighted with occupancy estimates - for example, in the case of the light rail occupancy was estimated at 33%, as was bus rider occupancy.
And furthermore, who would use a 727 to get to work? Very few of us.
In the paper from which the graph was produced, written by David Banister of London's University College, it's argued that transport in general needs to reduce its dependency on non-renewable fuel choices for the environment, economic competitiveness and energy security.
But actually the arguments for using the bicycle, at least in short-distance traveling in urban environments, are much more personal.
Read more: http://www.treehugger.com/bikes/trying-travel-city-bikes-are-most-efficient-way-move.html