Some students in two Iowa school districts are riding in new hybrid buses. The 65-passenger machines were purchased by the Sigourney Community School District in southeast Iowa and the Nevada Community School district in central Iowa.
Over the next three years, researchers at Iowa State University will test their performance. Dennis Kroeger, with ISU’s Center for Transportation Research, says the buses are powered by an electric motor and a V-8 diesel engine. "It runs at the slow speeds with the electric drive," Kroeger explains, "and then once the bus exceeds 30 miles per hour, the diesel drive engages and takes over the drive wheels."
The buses also carry technology to capture energy from the brakes to help recharge the battery. Aside from reducing emissions, the hybrid buses are also expected to improve fuel efficiency. "The traditional bus gets between six-and-a-half and seven miles per gallon," Kroeger says, "we’re hoping to get that into double digits (with the hybrid bus) at 11 or 12 miles per gallon."
Is it possible that one day all Iowa school buses will run on hybrid technology? "That’s a little hard to say right now. Our hope is to get as many of these out as possible," Kroger said. "It is a good technology to go and try and stretch the fuel dollars and reduce emissions. It’s a step in the right direction." A total of 19 hybrid buses are being tested in 11 states. The nonprofit corporation Advanced Energy, based in Raleigh, North Carolina, is coordinating the effort.
Kroeger helped secure grants to help pay for most of the $217,000 cost of each bus in Iowa. The Sigourney and Nevada School Districts each paid about $70,000, the cost of a conventional bus. Both school districts will hold brief ceremonies on Thursday to show off the buses to their communities and offer short bus rides.