The EPA says 24 million children in the US ride the school bus every day. That's a lot of emissions (even not counting the erasers emitted from kid's hands into the atmosphere of drivers' heads). Commercial hybrid-drive developer Enova Systems and IC, the largest school bus manufacturer in North America have worked up a prototype hybrid school bus with a diesel-electric powertrain they say could yield a 40 percent increase in fuel economy, with a commensurate reduction in emissions. The bus in question, powered by Enova's post-transmission 80 kW mild hybrid system, is undergoing testing at IC's Fort Wayne, Indiana plant and will be delivered to a customer later this year. Still, the system doesn't address the amount of time school buses are spent at idle, which may be the most serious emissions threat from big yellow, but it's a start.
IC Corporation to develop first Hybrid school bus [Casanova Cars]
US Marines Sweeten Contract for RST-V Hybrid Vehicle [internal]