Case Study: The Total Cost of Ownership for Propane Autogas School Buses

October 11, 2018

Written by Todd Mouw – October 10, 2018

School transportation departments across the nation must work within tight budgets and evaluate bus choices based on total ownership costs. Testimonials from school district transportation managers demonstrate the fuel and maintenance savings from propane autogas-fueled buses.

Clear Creek Independent School District in League City, Texas
Clear Creek ISD operates a fleet of 315 diesel, gasoline, compressed natural gas and propane autogas school buses, transporting 17,000 students throughout the Houston area. Thirty-seven are Blue Bird Vision Propane school buses from model years 2014 to 2018, purchased using grants from the Texas Commission on Environmental Quality.

According to Fleet Manager Ken Winters, the school district’s propane buses average a savings of $0.15/mile compared with its diesel buses.

“Our propane buses don’t get quite as good miles per gallon as diesel, but it’s close,” he says.

Part of the school district’s savings come from lower fuel costs. On average, propane costs 40% to 50% less than diesel. Clear Creek ISD currently pays $2.24 for diesel and $1.13 for propane, which has gone as low as $1. This makes a savings above average at up to 55% per gallon.

Most of the metrics kept by Clear Creek ISD have been on maintenance savings. Winters says that diesel emissions are now the highest expense in his shop – even higher than air
conditioning – due to emissions standards getting stricter and as the district’s diesel buses age (above 70,000 miles).

“School buses, in general, don’t average or maintain a high enough speed to burn up the diesel particulate matter, which causes carbon build-up. Houston is so densely populated that our buses rarely go above 40 miles per hour,” says Winters.

In addition to lower fuel costs, oil changes have been cheaper with propane buses. The school district spends about $150 for diesel compared to $50 for propane per oil change. And, Winters notes, there has been less downtime with propane buses, saving the district time and money. Winters believes the school bus industry will continue to get away from diesel and toward propane autogas because of the complications of diesel emissions and propane’s lower costs of ownership.

Cook-Illinois Corp. in Chicago
School bus contractor Cook-Illinois Corp. owns a fleet of 2,200 school buses. About 250 are Blue Bird Vision Propane or Micro Bird Propane buses model years 2010 to 2018. These buses are used for daily routes, charters and field trips for multiple school districts in high-traffic areas around Chicago. Complications with diesel buses led Cook-Illinois to adopt propane buses.

“Between 1980 to 2007, diesel was the best application for school buses,” says John Benish, Jr., CEO. “But government regulations have gotten stricter, and new clean-diesel buses aren’t as reliable as they used to be.”

Cook-Illinois paid $10,000 more per propane bus compared with diesel. The company received $7,000 back on each bus purchase from a diesel emission reduction grant. Benish says they make up the remaining incremental cost within three years with fuel and maintenance savings.

Over the years, Cook-Illinois has had to rebuild a lot of diesel bus engines. Plus, because of Chicago’s harsh winters and salted roads because of the snow, the diesel equipment under the bus frequently gets damaged. The company has replaced 40 engines due to premature engine failure in the past five years alone. Before the latest emissions standards, replacing diesel engines was uncommon.

“All of today’s diesel buses require complicated emissions maintenance,” Benish says. “All that equipment is not required on a propane bus.”

The company is experiencing about 50% savings per propane bus in parts and labor compared to diesel. When it comes to fuel, the company has experienced some huge savings. Currently, Cook-Illinois is paying $2.85 to $3 for a gallon of diesel. In comparison, the company has an annual contract for propane and pays between $1.10 and $1.30 – which is 80% less than diesel. In addition, Cook-Illinois saves more by taking advantage of alternative fuel tax credits.

“School bus contracting is a very competitive market,” Benish adds. “School districts like that we’re green, but at the end of the day, they need to stay within their budget. If I can achieve a cleaner footprint, do it for less money and still provide the same service? School districts value that.”

Because of the quick return on investment realized with propane autogas buses, Benish expects his fleet to become 50% propane autogas-powered.

Upper Moreland School District in Willow Grove, Pa.
The 59-vehicle fleet of Upper Moreland School District includes 35 MY2017 Blue Bird Propane Vision school buses and two Micro Bird Propane school buses. Each bus travels between 10,000 to 12,000 miles per year in the hilly region in stop-and-go traffic. The school district explored propane buses when its aging diesel buses became too costly to
manage.

“Our fleet was getting older and had been refurbished. It was becoming very expensive to maintain,” says Kelly Rhodunda, transportation manager. “Rising fuel prices and vehicle replacement costs were also a factor, combined with budget constraints. We had not purchased a new 72-passenger vehicle in more than six years prior to buying our propane buses.”

Although the incremental cost for the propane buses was $10,000, the district received
grant funding of about $630,000 for the buses and infrastructure. Propane autogas fueling infrastructure costs less than any other transportation energy source — conventional or alternative. The district also applied for alternative fuel tax credits.

In their first year of operation, the propane school buses saved the district approximately
$173,000 in maintenance costs and $77,000 in fuel costs compared with diesel. Currently, the Upper Moreland School District pays $2.32 per gallon of diesel compared with their five-year contracted price of $.76 for propane – making it 65% cheaper.

“The affordable cost of the infrastructure and fuel and a lower incremental cost for the
equipment were the most cost-effective decisions our district could make for this long term investment,” says Rhodunda.

About 850 school districts across the U.S. and Canada operate Blue Bird propane autogas school buses. These districts show that whether it’s for a few dozen or a couple hundred, propane autogas school buses make financial sense.

Todd Mouw is president of ROUSH Cleantech, a developer of propane autogas and compressed natural gas fuel system technologies. He can be reached at todd.mouw@roush.com.