A quick aside about pedal bikes being green... It turns out bicycling isn't as green as we think. The amount of food you need to eat to generate those calories has a cost. You need to account for the fuel that went into growing the plants, transporting them, etc. If you are a meat eater (mmmm, steak), then you need to do all the previous calculations and add in the addition time for that animal to convert those plants to delicious meat, and then the cost to slaughter and transport.
Here is a quick link: The REAL Carbon Footprint of Bicycles | The Worst Thing in the World
, there are others.
That said, it's better than taking the car, and you get healthy from it. But it is worthwhile to consider the whole supply chain when we bring up "being green".