26 million children in the U.S. rely on 480,000 buses to and from school each day. 90% of these buses run on diesel, accounting for more than 5 million tons of yearly greenhouse gas emissions.

Diesel school buses release harmful levels of particulate matter and nitrogen oxide- poisonous gasses known to have links to cancer, asthma and impaired cognition, making them a serious threat to children’s developing brains and respiratory systems. Unfortunately, children often breathe the most polluted air while riding in those buses, especially when idling in traffic or in pickup lots. The burden of these health concerns disproportionately affects students with disabilities, those from communities of color and low-income families who commute longer distances to and from school.

In comparison, electric school buses (ESB) emit fewer emissions and are better for students, drivers and the communities they serve. Unfortunately, the cost of new electric school buses can be four times higher than that of diesel ones.

The recent funding from the Federal government is sure to jumpstart the transition of school fleets to electric, but the cost of a new ESB, along with the manufacturing and supply chain constraints restrict the number of new buses that can be produced to replace the half million gas-guzzling buses on the road today.

But, there is an affordable and faster solution. Repowering existing diesel buses to electric.

Electric repower, also called electric conversion or retrofitting, is an affordable and sustainable alternative to manufacturing new buses. Instead of purchasing an entirely new fleet of buses, districts can repower their existing diesel buses - a more affordable, less wasteful alternative to accelerate school bus electrification.

So how does it work? An existing school bus from the fleet is chosen and examined for structural integrity and compatibility with electric parts. The internal combustion engine parts, including the engine, tailpipe and fuel tank, are replaced with an electric drivetrain that includes batteries and a motor. Finally, after inspection, the bus is commissioned for use.

A Cost Comparison 

A new electric model for the most common large school buses can cost up to $440,000. A new diesel-powered bus of the same size costs $100,000. Comparatively, repowering a diesel-powered bus into an electric can cost between $110,000 to $180,000, less than half the cost of buying a new one.

Electric school buses - new or repowered, need less maintenance because they have fewer moving parts. The lower maintenance and fuel savings an electric school bus provides can range between $4,000 and $11,000 per school bus every year, depending on labor costs, local electric utility rates and the price of diesel fuels.

Forth is working on Oregon's first repower project by converting a mid-life diesel school bus to electric to demonstrate an affordable and sustainable system to provide zero-emission bus rides for students. The repowered bus will serve Title 1 schools, which are schools with the highest number of students from low-income families.

Choosing to repower these vehicles instead of buying new ones is a critical step in converting America’s school bus fleets, making the transition to electric not just faster but also more equitable, and most importantly, cleaner for our children and communities.

For more details on the cost comparison and the repowering process, read the whitepaper on "Reduce, Reuse, Repower: The Benefits of Electric School Bus Repowers."