Making yellow school buses a little more green
A growing number of districts dropping fossil fuels for transit
Just ask any parent — yellow school buses, with their classic look, signature smell and rumbling sound, remain largely unchanged from decades past. But with advances in technology, those old buses are beginning to reach the end of the line.
A small but growing number of school districts are beginning to replace these older fossil fuel models with new electric buses. Motivated by evidence of the harmful effects of particulate emissions on both students’ health and performance and in an effort to reduce fuel costs and save on maintenance, a few innovative districts are making the transition.
The biggest obstacle is the significantly higher cost of electric buses, which can be at least two to three times as expensive as replacement buses powered by diesel or another alternative fuel (there are also costs associated with installing charging equipment). Districts are getting help to offset the extra costs from sources including grants and legal settlements. And several utilities, motivated by environmental concerns as well as the potential to help lighten the electrical grid load, have stepped up to help hasten the process.
On Dec. 16, Dominion Energy, a utility based in Richmond, Va., announced that it had chosen Thomas Built Buses, one of the oldest school bus manufacturers in the United States, to provide 50 electric school buses for districts across its home state. Sixteen school districts, including Alexandria, Arlington, Norfolk and Richmond City, are the first recipients, Dominion said in a statement Jan. 16.
Under the program, Dominion, which provides power to about 7.5 million customers in 18 states, will pay for infrastructure like the wiring and charging stations. An electric bus can cost as much as $400,000; the utility will absorb the $200,000 or greater cost difference between a diesel and an electric bus because many school districts find that prohibitive.
While estimates vary, Mark Webb, senior vice president and chief innovation officer for Dominion, said in an interview that the initiative is part of the company’s overall efforts to help reduce pollution and increase sustainability. “Transportation is the No. 1 source of emissions,” he said.
The announcement is just the first phase of the utility’s plan, Webb said. Dominion wants to increase the number of electric buses on the road so that by 2030, 100 percent of the new purchases are electric.
The Thomas buses, averaging 134 miles on a full charge of their 220 kilowatt-hour battery, are a blending of old and new. The company, which is based in High Point, N.C., began as a streetcar manufacturer in 1916 and started producing buses a little more than 80 years ago, said Caley Edgerly, the president and chief executive.
Its electric buses, named Jouley, not only draw from innovation within its parent company, Daimler, but also incorporate the technology of Proterra, an electric transit bus and battery manufacturer based in Burlingame, Calif., that has contracted to provide electric transit buses to 100 cities in the United States and Canada. “We’re not reinventing the wheel, but we’re modifying the wheel to fit a different vehicle and a different duty cycle,” Edgerly said.
Dominion is following other utilities into the electric school bus market, including Consolidated Edison’s pilot project in White Plains, N.Y., and the Sacramento Municipal Utility District in California. The utilities’ interests stem from two distinct goals.
The first is the impact the buses have on reducing pollution. School buses are often thought to be the safest form of transportation for children, “yet, when you look at the particulate emissions from tailpipes, buses are not the safest when it comes to health,” said Tim Shannon, the director of transportation for the Twin Rivers School District in Sacramento, which operates 25 electric school buses built by
Lion Electric in Canada, believed to be the largest fleet in the country.
The impact of pollution on health has long been documented, but two recent reports highlight the effect of emissions on academic performance as well. One study showed that students in schools that are “downwind” from major highways score lower than those in upwind schools, while another looked specifically at the decline in academic performance, particularly in English, that correlates with time spent on a diesel bus.
The electric bus manufacturers, including Blue Bird, based in Fort Valley, Ga., which has supplied those used in the Con Edison trial, and Navistar, based in Lisle, Ill., which hopes to ship its first models this year, recognize that this is a potentially huge market.
Approximately 26 million students ride on 485,000 school buses nationwide, said Michael Martin, executive director and chief executive of the National Association of Pupil Transportation. While electric transit buses have been in operation for years, the school bus market — which when aggregated comprises the largest fleet nationwide — has been slow to adapt.
The reason is largely economic: Electric buses are more expensive. For transit buses, which may travel 50,000 miles per year, the savings in fuel and maintenance make the transition cost effective. School buses, in contrast, on average can cover 12,000 miles per year, and, as a result, it can take years to offset the higher purchase price.
While prices are expected to drop as technology develops and more districts buy the new buses, for now, state grants and funds available from the Volkswagen emission scandal settlement, in addition to the utilities’ investments, can offset the price. Shannon said Twin Rivers’ costs were offset in part by California state grants.
The manufacturers of electric buses would not disclose the price of their vehicles, which can vary, partly because of differences in state emissions regulations.
The grants serve another purpose. They enable school districts irrespective of affluence to provide their students with reduced pollution. Twin Rivers, for example, is a “disadvantaged community,” Shannon said, with a large immigrant population “speaking 46 languages.” Webb echoed that sentiment, saying, “We want to ensure that schoolchildren in lower-income areas will have the same opportunities that the wealthier suburbs do.”
This is especially important because the electric school bus math — fuel and maintenance savings versus those of a diesel counterpart — can depend on differences like the length and location of a bus route. Urban routes, which require more stopping and starting, may be less efficient than rural routes with longer, unimpeded distances. Other factors affect performance as well, like weather (batteries typically are less efficient in colder weather) and the overall terrain.
Shannon said that the fuel costs for a diesel bus were about 85 cents per mile, as opposed to 19 cents for an electric bus, depending on “how well the driver drives and whether he or she takes advantage of the regenerative braking,” the process in which braking itself creates energy that is accessible for the vehicle. Some are “keeping their costs as low as 16-17 cents per mile. Except for a few who drive with a lead foot,” he added. In addition, because electric buses have fewer parts, maintenance is less costly. Yet, despite these savings, because school buses do not travel as much as municipal transit buses, it can take years to recoup the additional cost of an electric vehicle.