• Posted May 22, 2024

Health Savings Could Near $250,000 When Electric School Bus Replaces Diesel

It might be hoped that replacing a diesel school bus with a clean electric model would pay off for health and the environment.

New research suggests that it does -- and gives a dollar figure for that payoff.

Replacing a diesel bus with a clean electric model yields up to $247,600 in climate and health benefits per bus, according to research from Harvard University's T.H. Chan School of Public Health.

The savings come from lowered rates of child asthma, fewer greenhouse gas emissions and extended lives for adults, said the team led by Kari Nadeau, a professor of climate and population studies at the school.

"Our data offer strong evidence that accelerating the ongoing transition to electric school buses will benefit individual, public and planetary health," she said in a Harvard news release.

Nadeau's team estimated that half a million buses currently transport America's children every day. A big percentage of those vehicles run on polluting diesel fuel.

Of course, a switch to expensive electric buses is a tough decision for cash-strapped school districts. Is it worth it in the long run?

To find out, the Harvard team calculated the cost to the environment and to human health of the emissions from diesel-fueled buses' tailpipes and the energy needed to power the batteries of electric buses.

Key to this equation was the generation of fine particulate air pollution (PM2.5), a major airborne culprit for child asthma and adult death rates.

Based on 2017 data, replacing a diesel school bus with an electric one resulted in $84,200 in total benefits per bus, Nadeau's team calculated.

"Each electric school bus emitted 181 fewer metric tons of carbon dioxide than its diesel counterpart, amounting to $40,400 worth of climate benefits," according to the news release. "Meanwhile, each electric school bus was associated with $43,800 in health savings, from less air pollution and reduced rates of mortality and childhood asthma."

Urban school districts tended to reap these health (and financial) dividends more than rural ones, because changes in air quality affect a much larger number of people.

For example, in a large city, switching a 2005 diesel school bus with an electric bus would net $207,200 in health benefits per bus, the Boston team found.

"In a dense urban setting where old diesel buses still comprise most school bus fleets, the savings incurred from electrifying these buses outweigh the costs of replacement,"Nadeau explained. "Not to mention how the tangible benefits of electric school buses can improve lives -- especially for racial minorities and those living in low-income communities who are disproportionately impacted by the everyday health risks of air pollution."

She noted that one important health factor, kids' exposure to air pollution while inside the bus, wasn't even tackled as part of this study.

The findings were published May 20 in Proceedings of the National Academy of Sciences.

More information

The EPA has more on the benefits of electric school buses.

SOURCE: Harvard T.H. Chan School of Public Health, news release, May 20, 2024