Letter to the Editor: Diesel technology updates mean better buses

As an education advocate myself, I feel it’s critical that we depend on the facts and instill their importance on the younger generations. However, it seems that opinion doesn’t seem to be shared by the electric school bus “movement.”

In a previous commentary, electric school buses were identified as the answer to myriad problems, including climate change, air pollution, disadvantaged communities, boosting performance of disabled students and more. (“Are diesel-powered school buses safe for students?” May 10) Perhaps public funding and a cause can cloud one’s objectivity.

Diesel has long been the technology of choice for pupil transportation because of the fuel’s safety. It is less combustible than gasoline; the engines have excellent reliability and durability to maintain uptime; the cost of ownership is low; parts are available nationwide, along with servicing and fueling networks; and used buses have high resale value.

Arguments for switching from diesel to electric buses today are selectively based on a few decades-old studies on old-generation diesel buses. As of 2021, 6 out of 10 diesel-powered school buses on the road in Delaware are of the newest generation diesel technology, equipped with particulate filters and selective catalytic-reduction systems that effectively achieve near-zero emissions. The Health Effects Institute extensively studied the new generation of advanced diesel technology and found the emissions-control systems to be extremely effective at reducing emissions and eliminating any concerns about toxicity.

As for the role of school buses in battling climate change, buses travel comparatively fewer annual miles and use far less fuel than commercial vehicles. Making them electric will have a high cost but very low benefit, considering that they often are sitting still for two or three months a year. School buses’ contribution to emissions is so small it does not register as a separate category in the state’s air emissions inventory.

The more important lesson about switching to electric school buses is that doing so could actually be worse for the climate. That’s because in Delaware, and nearly all other states, the electricity required to power electric buses comes from natural gas and coal. According to the Department of Energy, in 2020, resources used to generate electricity included 72% natural gas, 25% coal and less than 3% renewable sources.

It’s tragic that any child must suffer from asthma but drawing a direct line to the type of school bus as the cause or solution is well beyond a leap. Consider that the Centers for Disease Control and Prevention reports that smoking and vaping are rising in Delaware with “alarming” teen vaping rates, according to the American Lung Association. “While all of the causes of asthma remain unclear, children exposed to secondhand tobacco smoke exposure are at increased risk for acute lower respiratory tract infections, such as bronchitis,” writes the U.S. Department of Health and Human Services. “Children living below or near the poverty level are more likely to have high levels of blood cotinine, a breakdown product of nicotine, than children living in higher income families.”

According to the Delaware Department of Natural Resources and Environmental Control’s latest available data, “in 2019, all pollutants except ozone were below the national health-based air-quality standards. Concentrations of air toxics in Wilmington continue to show generally low or declining levels. As measured by the air quality index (AQI), there were only three days that fell into the category of moderate or unhealthy for sensitive populations. Continuing recent trends, the number of days with good air quality continues to increase.”

One thing we know for sure is that getting more advanced diesel technology buses in service and replacing the old ones as fast as possible will do more for air quality, children’s health and climate far faster than getting a token few electric buses to satisfy a movement.

Allen Schaeffer

Executive director, Diesel Technology Forum

Frederick, Maryland

Editor’s note: The Diesel Technology Forum is a not-for-profit educational association representing diesel engine, equipment and vehicle manufacturers, petroleum and renewable-fuel producers, and emissions-control technology suppliers.