From: , Green Progress, More from this Affiliate
Published August 21, 2007 09:21 AM

California's First Plug-In Hybrid School Bus

Enova Systems, a production company in an emerging clean energy, environmentally friendly industry and a developer of proprietary electric, hybrid and fuel cell digital power management systems, announced today that the Napa Unified School District has received a new plug-in hybrid electric school bus. The bus, provided by IC Corporation could see up to a 100% fuel economy improvement, as well as a 90% reduction in emissions.

More than 150 attendees were on-hand Friday at a ceremony in Napa when the hybrid school bus was officially delivered. The school district will become the first in California, and one of only eight school districts in the U.S., to operate the new hybrid school bus that has the potential to double fuel efficiency and reduce emissions by up to 90 percent.

Mike Staran, Enova's President and COO, said, "Enova's alliance with IC Corporation is very strong and we look forward to growing together in the North American bus market. We expect significant short and long term opportunity in this market."

The new bus is a result of a nationwide initiative called the Plug-In Hybrid Electric School Bus Project, led by Raleigh, N.C.-based Advanced Energy, a non-profit corporation that initiated a buyer's consortium of school districts, state energy agencies and student transportation providers. The hybrid plug-in school bus is built by IC Corporation, the nation's largest school bus manufacturer. The hybrid school buses are manufactured at IC Corporation's plant in Conway, Ark. Randall Ray, IC Corporation's Platform Manager on the hybrid school bus project, stated, "The development of the Enova hybrid system integrates well with both our chassis and the duty cycle of a school bus, we feel this should provide a significant step forward for everyone involved."

While the exterior of the hybrid school bus looks the same as a standard school bus, it is powered with innovative new technology. The hybrid school bus project features Enova's Charge Depleting System (or "Plug In"), which was extensively evaluated at IC Corporation's research and technology facility in Fort Wayne, Ind.


The initial powertrain for the hybrid school bus will couple an International MaxxForce 7 diesel engine with the 25/80-kilowatt hybrid-electric powertrain, incorporating a transmission, batteries and an electric motor. The Post Transmission System is one in which the Electric Drive System is integrated behind the Transmission and is designed to be installed as a "drop in," fully integrated turnkey fashion into an OEM production line, or retrofitted in post vehicle production in a modular, "as-needed" basis. Enova's Post Transmission System has proven, in other applications, to be a non-invasive system that has required little to no modifications to chassis, body, instrument panel, etc. In addition, our system does not intrude on the Engine Control/Communication system. The system monitors, but does not impact the engine operation parameters within the diesel powerplant.

Enova's Charge Sustaining System utilizes relatively small batteries which are maintained within a specified range of State of Charge (SOC) over the entire drive cycle. Battery charge is maintained by the on-board equipment and is not normally recharged from the grid except as needed for cell balancing. The Charge Depleting (or "Plug In") System utilizes a larger battery based on advanced battery chemistry that provides stored energy intended to be drawn down over the driving cycle, thus optimizing fuel economy, subsequent to an overnight charge.

Depending on the route, fuel economy miles per gallon (mpg) improvement is from 30% to 55% for a Post Transmission Charge Sustaining System, and as much as 70-100% for Post transmission Charge Depleting Systems. Emission improvements vary with the pollutant being measured and has shown up to a 90% improvement at times on Particulate Matter based on load and operating conditions.

Terms of Use | Privacy Policy

2017©. Copyright Environmental News Network