The Big Green Bus  

PhysOrg has an article on a new, more efficient hybrid bus made using a lightweight nitrogen-strengthened stainless steel - Revolutionary green technology bus.

Insight from Oak Ridge National Laboratory, commitment from two Michigan companies and funding from the Department of Energy have led to the commercialization of a lightweight urban transit bus with double the fuel efficiency of conventional hybrid buses.

This new green technology 40-foot bus features a high-strength stainless steel body and chassis and a hybrid power system that drives the bus primarily with stored electrical energy. This approach reverses the paradigm of conventional parallel hybrid designs that use electric energy only to supplement the acceleration and torque requirements of a diesel engine.

At the heart of the bus is a chassis made of Nitronic 30, a nitrogen-strengthened stainless steel that is stronger and stiffer than conventional steel. These attributes translate into less material required for a chassis, resulting in reduced weight.

"Nitronic stainless steel is incredibly durable and enables our chassis designs to have significantly longer service life vs. ordinary steel vehicles," said Bruce Emmons, president of Autokinetics (http://www.autokinetics.com/) of Rochester, Mich., which developed the bus. "The fact that stainless is also 100 percent recyclable and more environmentally friendly to produce than aluminum makes this an ideal green raw material for vehicle structures."