Citizens living in Oslo, Norway will be greeted by new trains at the station. Developed by Siemens Transport Division, the trains are said to give off 2.6 grams of carbon dioxide every kilometer traversed, which is a small fraction of what efficient cars emit. So how are these trains so green?

The electric subway cars have aluminum hulls which are not only lighter, but contribute to the carriages being 94% recyclable when they are retired. The trains also ease their own power demands by taking advantage of regenerative braking — much like many hybrid automobiles. Project leaders hope that once all of the trains are deployed, numbering over 100, Oslo will be able to boast that its subway is the most green, efficient subway system in the world. — Kevin Hall

Via Treehugger

CORRECTION: Braking it is. Thanks, mediumsteve.