Over 20 million American students each day board one of nearly 500,000 school buses to and from their schools. Unfortunately, 95% of these vehicles run on diesel fuel and are frequently idle, directly contributing to climate change and health issues like asthma, cancer, and premature death. These health effects primarily affect children with still-developing respiratory systems.
Fortunately, an increasing number of municipalities are adopting a solution: electric buses. These large EVs address both climate and health concerns. On the environmental impact, replacing one diesel bus with an electric one equates to a 54,000 lb annual greenhouse gas emission reduction.
For health advantages, a zero-tailpipe pollution vehicle reduces the most harmful emissions: nitric oxides, particulate matter, and unburned hydrocarbons. However, toxic tailpipe exhaust can permeate the bus’s interior during idling, entering the cabin air supply the students and driver must breathe. A 2002 Yale study found dangerous particle levels were five to ten times higher while buses during idle operation.In addition to the known climate and health advantages, electric buses carry secondary benefits of reduced noise pollution and maintenance: the large-profile vehicles are adept for vehicle-to-grid (V2G) charging and emergency power. Electric buses also offer lifetime cost savings over diesel due to the decreased maintenance, higher efficiency, and elimination of high-cost diesel fuel.The advantages of electric school buses are clear, and demand has been overwhelming. However, as with many EVs, the vehicle cost is the challenge to mass adoption. In addition, schools have limited revenue, as states designate a fixed amount that schools receive each year based on student population. As a result, there is a significant gap between vehicle cost and available funds to pay for it. Fortunately, there is substantial public funding available allocated to this endeavor.
The US Environmental Protection Agency (EPA) has a new Clean School Bus Program, which designates $5 billion to replace existing diesel school buses with zero- and low-emission ones over the fiscal years 2022-26. In addition, other funding for e-buses may be available through state governments, which fund US public schools.Over 90% of the 2,000 applications the EPA received (equating to $4 billion of funding) were for electric buses, dominating the share of other fuel types. For example, applicants selected electric drivetrains over propane fuel by a factor of 10 to 1, and the ratio of electric to compressed natural gas is closer to 200 to 1. The EPA has announced awards by school district for the 2022 funding year.
In addition to the substantial federal plan, individual states also fund electric school buses. For example, this year, Colorado created a $65 million grant for electric buses. One noteworthy outcome when comparing the funding strategies is that federal funding typically prioritizes rural and tribal districts, whereas Colorado’s will prioritize high-poverty schools not selected for federal dollars.However, despite the infusion of funding from the federal and state governments to date, Colorado still does not have the funds to convert all 178 school districts to electric buses. A positive signal that electrifying school bus fleets is a universal priority is that there are some private funding options, such as Virginia’s Dominion Energy utility. At the moment, however, there are still not sufficient funds to convert all existing diesel buses to electric.
Despite the current funding shortfall for the total conversion of diesel school buses to electric, the movement is worth supporting. Electric buses work in all topographical conditions, including mountain and cold weather. An example of this performance enhancement is bus manufacturers developing heat pump systems for more efficient heating and range extension. Also, large bus batteries are well-suited to vehicle-to-grid supplemental energy storage and grid mobility.Taking advantage of this funding is critical to protecting our school-age children and the health of society. Electric buses also offer significant energy, climate, and performance benefits over diesel buses to accompany the improvement to human health. State and local governments have allocated this funding; it’s now up to districts to use the funds to convert as many diesel buses to electric as possible.