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New Jersey Contractor Pilots Dual-Fuel RNG System
B.R. Williams is the first in the state to deploy the DEMI-NeuFuel platform, a conversion technology blending renewable natural gas with diesel to extend fleet sustainability.

The DEMI-NeuFuel system helps B.R. Williams cut diesel use by nearly 2,000 gallons a year while reducing greenhouse gas emissions.
Photo: Ingevity
New Jersey school bus contractor B.R. Williams recently announced it's the first in the state to pilot the DEМІ-NeuFuel school bus platform (aka the CowFartBus) to run on a blend of renewable natural gas (RNG) and diesel.
The DEMI-NeuFuel system, made possible through a partnership between American CNG and Ingevity, allows operators to convert existing diesel school buses to run on a blend of diesel and RNG.
According to a company release, the process allows for a cost-effective way for school bus contractors and districts to reduce fuel costs with the use of natural gas and a low-cost and small footprint fueling appliance. Additionally, the DEMI-NeuFuel system's dual-fuel capabilities eliminate the range anxiety that many drivers experience.
"We are excited to be the first school bus operator in New Jersey to implement the DEMI-NeuFuel platform," said Chloe Williams, president at B.R. Williams Inc. "This technology offers a cost-effective and environmentally responsible solution for reducing our carbon footprint on our existing diesel vehicles."
How Does DEMI-NeuFuel Tech Impact Sustainability Goals?
Through the use of the DEMI-NeuFuel technology and RNG, B.R. Williams can reduce its annual fuel costs by over 60% on the displaced diesel, eliminating approximately 1,945 gallons (based on 17,000 miles per year, 7 mpg and $3.50 diesel and $1 NG price for two buses) of diesel per year, and reducing greenhouse gas (GHG) emissions by approximately 20 metric tons per year, which is the equivalent of 10,800 miles driven by a diesel school bus.
B.R. Williams joins a growing number of school bus contractors and districts nationwide that are working to reduce emissions. The use of the DEMI-NeuFuel system is part of a broader effort by B.R. Williams to maximize its environmental stewardship while also enhancing its fiscal responsibility with the use of cleaner, more cost-effective fuel solutions for student transportation.
"Ingevity is proud to support B.R. Williams and school districts around the country on their sustainability journeys," said Dante Marini, product engineer at Ingevity. "Our DEMI-NeuFuel technology offers the flexibility school bus fleet operators need to meet their operational requirements without compromising performance or efficiency. We are excited to continue advancing clean energy solutions for school transportation."
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