The basic yellow school bus hasn't changed much in 30 years: a shoe-box-on-wheels built to transport kids safely at low cost.
Now Ewan Pritchard wants to turn that soot-spewing school bus into a clean, green plug-in-hybrid machine. High mileage. No more exhaust cloud at each stop.
When Mr. Pritchard, a mechanical engineer, unveiled his plan to a major bus manufacturer in 2002, snickering officials nearly laughed him out of the room. That was before hurricane Katrina hit, and diesel prices skyrocketed.
"When we first talked about this, manufacturers acted as if we were asking them to build flying cars or something," says Pritchard, hybrid program manager for Advanced Energy, a small nonprofit energy-consulting company in Raleigh, N.C.
That laughter has subsided. Now, the nation's biggest school-bus maker has orders for 19 buses from districts in 11 states – including Washington, California, Texas, Iowa, Arkansas, and North Carolina.
In Bradenton, Fla., Manatee School District officials last month became proud owners of the nation's first two plug-in hybrid school buses. Students are catching the spirit of their new ride, too. Emily Mulrine, a district student, helped name her middle school's new plug-in hybrid bus "Limpio," the Spanish word for clean.
Such plug-in hybrid buses use both a diesel engine and an electric motor – plugging into a power socket at night to charge batteries. Environmentalists and energy-security hawks love the idea.
"Buses are a great way to use off-the-shelf technology that can reduce pollution and energy use," says Roland Hwang, senior policy analyst at the Natural Resources Defense Council. "This move creates greater pressure on the automakers to produce similar technology."
Indeed, while big automakers tout plans to build plug-in hybrid cars a few years from now, Navistar International Corp.'s school bus division, IC Corp., is already rolling out plug-in hybrid buses. This week, another one will be delivered in Pennsylvania.
To some, it's nothing less than a role reversal in innovation.
"The school-bus industry is usually 10 to 12 years behind," says Bill Schroyer, director of fleet management for the Florida Department of Education. "It was a surprise to see them do this and jump ahead. From the plug-in standpoint, we're ahead of the auto industry."
It's a big deal to the school-bus industry as well.
"There is a huge shift going on – a seismic shift in mind-set and in technology for us and for schools," says Randall Ray, manager of bus platform marketing for IC Corp., based in Warrenville, Ill. "Plug-in hybrid buses are a very viable system, and we have high expectations for it."
Other efforts to clean up school buses have emerged over the years. Some districts still employ a handful of all-electric or compressed natural-gas buses. Maintenance costs were high for CNG, and range of driving was a problem for electric, analysts say.
Fuel prices and concerns about global warming could increase receptivity to plug-in hybrids. But all agree the cost needs to come way down first.
"There's definitely a lot of interest," says Ryan Gray, senior editor at School Transportation News, a trade publication based in Los Angeles. "Fuel savings holds a lot of weight for people."
Each of the first 19 buses costs over $200,000 – more than double the cost of a regular model. At that price, they won't pay for themselves over their lives, even with superior fuel savings. It's a chicken-and-egg problem because until about 1,000 buses roll off assembly lines, the cost of production will keep prices high.
Even after manufacturing efficiencies and competition bring the price down, plug-in hybrid school buses may still cost $40,000 more than a regular bus. But at that point, they will pay for themselves in just a few years with lower maintenance and fuel costs, analysts say.
Ordinary yellow "type C" school buses get about 6 to 8 miles to the gallon. But the new plug-in hybrid models, rated at more than 12 m.p.g., could cut fuel consumption about in half in many districts. That could mean a big fuel savings for tight budgets.
If the nation could double its fleet miles, school savings could be significant. About 475,000 buses transport 25 million kids each day. Traveling more than 4 billion miles a year, those buses burn about 550 million gallons of fuel annually, Mr. Gray says.
"If we could cut our fuel use in half, boy, we've done something good," says Mr. Schroyer of the Florida Department of Education. "It's that much less pollution, that much less cost."
Electricity isn't free, of course – and using it pollutes, especially in regions where coal-fired power plants predominate. Still, the price and emissions per mile powered by electricity are much less when compared with those of diesel fuel.
"It's definitely worth it to try this," says Ben Matthews, director of school support for the North Carolina Department of Public Instruction, which is buying two buses. "What we're buying is a prototype of the school bus of the future."
For Pritchard, the crusade isn't over. He's used up a small grant as seed money to help fund buses now being delivered. Now he's wishing the federal government would toss a few of its millions spent on energy research into deployment of plug-in buses.
"It's still very difficult to get people to fund this effort and buy into the idea," he says. "But in the long run, it's going to work."