Earlier this year, Orange Grove Charter School, based in Charleston, South Carolina, converted most of its diesel school buses to run on renewable natural gas (RNG) and converted its school bus fleet to the DEMI-NeuFuel diesel displacement platform.

The DEMI-NeuFuel school bus platform, commonly known as the “CowFartBus”, is made possible through a partnership between Ingevity, a specialty chemicals and materials manufacturer based in North Charleston, S.C., and American CNG, based in Layton, Utah.

This fleet conversion follows a successful pilot with the charter school upfitting an existing school bus with Ingevity’s NeuFuel technology and American CNG’s DEMI Diesel Displacer system. The platform enables buses to run on a blend of diesel and RNG. This near-zero carbon fuel is derived from the biodegradation process of organic matter from agricultural, landfill, and wastewater facilities.

The system is designed for use on in-service, existing diesel school buses and does not require districts or contractors to purchase new buses. According to Orange Grove CEO John Clendaniel, the new system will save the school $750 a month in addition to helping the environment.

“This project marks a significant step forward in our commitment to sustainable transportation and demonstrates how we can reduce our carbon footprint and provide cleaner air to our students and our community, while we remain financially prudent,” Clendaniel said.

RNG to Lower Costs and Emissions

Orange Grove’s school bus fleet will now rely on this sustainable platform, utilizing low-pressure technology to unlock the value of low-cost natural gas, specifically highly sustainable RNG, by installing a natural gas hookup on their Charleston campus.

Through the use of the DEMI-NeuFuel technology and RNG, Orange Grove projects a fuel cost reduction by over 25%, displacing approximately 270 gallons of diesel per month, and reducing greenhouse gas (GHG) emissions by 32.6 metric tons per year, which is equivalent to 18,549 miles driven by a school bus (based on EPA greenhouse gas equivalencies calculator and the Department of Energy’s AFLEET Tool).

“This project highlights the benefits of low-cost natural gas and zero-to-low carbon RNG as a transportation fuel designed specifically for school bus fleets supporting the transition to a lower cost and more sustainable mode of operations,” said Dante Marini, product engineer at Ingevity.

According to Marini, Orange Grove was able to run the technology for the last few months of the 2024-25 school year, with real-world usage showing similar results to their early projections.

“We are excited to have the full school year to realize the economic and environmental benefits of displacing diesel with renewable natural gas,” Marini said.

The team has done an excellent job in making the process seamless for drivers,” said Steve Arato Sr., Orange Grove Charter School bus driver. “Our drivers have all noticed a smoother and quieter operation, which makes for a better ride. Overall, I feel proud knowing that what I’m driving is good for the school financially and better for the environment.”