New research has found an even greater emissions disparity during real-world use between a propane autogas school bus and a diesel bus of the same model year than what previous laboratory tests had found.

Earlier this year, the Propane Education & Research Council contracted the West Virginia University Center for Alternative Fuels, Engines, and Emissions to compare the in-use emissions levels of a 2014 model-year propane autogas and diesel school bus using two distinct test routes. The study found the propane autogas school bus nitrous oxide emissions were between 93 and 97 percent less than the comparable diesel model. These percentages presented a larger disparity between the fuels than what was indicated during certification testing.

PERC intends to continue collecting data this summer to reinforce the initial findings.

Learn more about how school transportation officials can benefit big with propane autogas school buses.