Sometimes green tech can be simple

Like trying to save the lives of bicycle riders. If fewer of us drove everywhere and walked or rode a bicycle, it would reduce greenhouse gases. A peddling bicyclist does not exhale as much CO2 as an internal combustion engine over the same distance. There are few energy resources more renewable than human muscle power. And if the bicyclist eats organic food grown without commercial fertilizers...how green it is.

Now one American city is trying to save its bicyclists frlom extinction, or at least from being endangered. Portland, Oregon, wants to protect its bike riders from the rest of us.