Currently, the federal government is funding at least two retrofit programs to reduce emissions from diesel trucks and buses. These programs provide funds to install catalysts and other devices to reduce emissions of the six criteria pollutants in the Clean Air Act. We want to see similar retrofit programs for older gasoline vehicles. According the US DOT, the average age of a car in 2021 is 12 years. Approximately 65% of cars are at least five years old.
The EPA’s Diesel Emissions Reduction Act (DERA) funds grants and rebates to install catalysts and other devices on heavy-duty diesel trucks. The EPA’s Clean Bus Program (CBP) funds grants and rebates to install catalysts and other devices on older school buses to reduce emissions in order to protect human health and improve air quality.
The EPA also provides grant to replace diesel school buses with Electric School buses.
We reviewed published data from EPA on its Electric School Bus program, its Clean Bus Program, and its Diesel Emissions Reduction Act (DERA) program to estimate the cost per ton of total pollutants removed from the air. The EPA 2022 EV School Bus Program grants show that for a full-size bus, the grant amount is $395K. We used EPA data on school bus emissions published in 2008. The most recent EPA report on DERA provides data for 2017 and 2018. The report provides the total amount of EPA grants and the total reductions of pollutants. The report states that on average, for every EPA dollar, an additional $2.10 in funding was provided from other sources.