Across the U.S., school districts and transportation companies are adopting alternative-fuel vehicles as part of district and statewide initiatives to go green. While these alternative fuels can benefit the environment by reducing harmful emissions, they have also helped some operations save hundreds, if not thousands of dollars in fuel and maintenance costs each year — particularly with propane buses.

According to the Propane Education and Research Council (PERC), there are nearly 20,000 propane school buses on the road nationwide, and over 1.2 million students in 48 states are transported to and from school on a propane bus.

Last year, 15% of respondents in School Bus Fleet’s Annual District Fleet Survey who bought new buses chose propane-powered vehicles, and about 6% of respondents’ current buses were propane.

As the number of propane buses in the U.S. continues to increase, more school districts are realizing the benefits these buses can have on their transportation budgets. SBF spoke with operators and maintenance technicians in Colorado, Illinois, and Georgia to find out how propane buses have led to significant advantages for their operations — including reduced fuel costs, frequency of oil changes, and minimal cold-weather starts.

More Funding, More Propane

Over the past three years, Boulder Valley (Colo.) School District has added more than two dozen propane buses to its fleet, and nearly all of them were purchased in part with grant funding.

The district’s latest propane-powered vehicles — six Blue Bird Vision model year 2021 buses — were purchased with a little less than $400,000 of the state’s $68.7 million total share of Volkswagen (VW) settlement funds. Each bus cost approximately $110,000, and the funding covered about $30,000 per bus, according to Leslie Hornbaker, the district’s shop foreman. (The remaining VW funds were used to purchase one electric school bus for the district.)

“The two main reasons we started incorporating propane buses were fuel costs and pollution,” Hornbaker explains.

The buses are reportedly able to cut current tailpipe emissions by 66% and produce “near-zero” nitrogen oxide (NOx) emissions at 0.02 NOx, according to Ryan Zic, vice president of school bus sales for Roush CleanTech, the propane fuel systems supplier for Blue Bird.

On average, Hornbaker says, each of Boulder Valley’s propane buses travels up to 80 miles per day, totaling to about 6,000 miles each school year. The average cost to operate one of the district’s 37 propane buses is about $0.48 per mile compared to $0.72 per mile for a diesel bus, he adds. That means the district, on average, spends about $38.40 a day to run a propane bus versus $57.60 for a diesel bus. This rounds out to a total cost savings of $19.20 per day and more than $3,000 for a 160-day school year.

Hornbaker says that much of this cost savings is due to decreased fuel expenses, fewer oil changes, and propane buses not requiring diesel particulate filter (DPF) cleaning, which can be costly.

“As our diesel buses get older, they get more costly to repair and clean,” he adds. “We do the DPF cleaning at approximately every 50,000 miles on a diesel bus, which can cost up to $1,000 per bus, so that’s a huge savings for us.”

Easier Cold-Weather Starts

In Orland Park, Ill., American School Bus Co. (ASBC) — a subsidiary of school bus contractor Cook-Illinois Corp. — has experienced similar savings, even in cold weather, according to Clint Meadows, the company’s shop foreman.

Every month, ASBC monitors the miles per gallon (mpg) of its 81 propane buses, with each bus reportedly traveling up to 300 miles on a full tank and averaging about 4 mpg, he says.

Even though ASBC performs similar maintenance procedures for all 166 buses in its fleet, which also includes 48 diesel and 37 gasoline buses, Meadows says the cost of operating a propane model is about three-quarters less than a diesel model.

“It’s less oil changes and less fuel filters, so you don’t have to change them as often,” he says. “When changing oil on [a] propane [bus], we’re looking at seven quarts of oil versus 18 to 20 quarts [of oil] for a diesel.”

Using an oil monitoring system, ASBC’s maintenance staff performs oil changes every 8,000 miles or roughly once a year on all of its buses.

“When you change the oil from a propane bus, it’s clean,” Meadows says. “I’m sure in the long run this will pay off for the internal maintenance of the engine.”

Another cost-saving benefit, he points out, is the reduced time and fuel used for cold-weather starts.

“We used to start diesels early in the morning because you had to get them up and running in the cold weather,” he explains. “We don’t have to do that with propane.”

By running the buses for shorter amounts of time, Meadows says, the company can see returns on fuel costs and also reduce its emissions levels.

Greater Tech Efficiency

Historically, propane fuel has been about 50% less expensive than diesel, says Roush CleanTech’s Zic.

In Bibb County, Ga., the cost per gallon for propane is $0.95 versus $1.33 for diesel, according to Anthony Jackson, the transportation director for Bibb County (Ga.) School District. These figures have reportedly remained the same since the district added 31 propane buses to its fleet in 2016.

Today, the district runs nearly half of its fleet on the alternative fuel: a total of 97 buses out of 206. Since making the shift to propane in 2014, Jackson says the district has experienced a more than 28% reduction in fuel costs.

Each bus in Bibb County’s fleet runs up to 25,000 miles per year. For every two oil changes performed at 5,000-mile intervals, he says the district’s propane buses average almost 40% less in oil change costs than those required for diesel models, which are changed every 10,000 miles.

“The newest propane engine technologies are more efficient than older technologies still in use,” Jackson points out. “Each Blue Bird Vision propane runs on a Ford 6.8 liter V10 engine with a Ford 6R140 automatic transmission.”

He also says that installing a propane fueling station is less costly than other fueling stations, such as gasoline and CNG, because the EPA classifies propane as a non-contaminant and that the infrastructure for the alternative fuel has fewer compliance requirements.

Jackson encourages districts that are interested in adopting propane to reach out to operations that have firsthand experience with the alternative fuel.

“There are plenty of districts out there that have already made the transition [to propane] and they all seem to be willing to answer questions and share information with districts considering the change,” he adds.

“Your overall retention with customers, contracts, and employees are all important, and [using propane] is definitely more beneficial for the environment,” ASBC’s Meadows says. “At first it was new to [ASBC], but the cost savings has been the most helpful.”