Propane brings spark-ignited engine back to Kentucky

October 18, 2013 By    

It was a late night after a long day at Kings Island amusement park.

The bus was full of happy, exhausted teenagers and their chaperones making the 170-mile journey home to Radcliff, Ky., after spending the day on roller coasters and thrill rides. Sixty-six members of the Radcliff First Assembly of God Church and a driver made the May 14, 1988, trip to the theme park, north of Cincinnati, in the 1977 Ford B-700 former school bus they used for church excursions.

But 27 of them did not make it home.

Just before 11 p.m., a small Toyota pickup truck with an intoxicated driver traveling the wrong way on Interstate 71 near Carrollton, Ky., collided almost head-on with the bus, crushing its front door. As passersby and some passengers tried to evacuate the panicked children from the rear exit, sparks from the metal suspension ignited, leaking highly flammable gasoline from the punctured tank. Flames engulfed the bus, killing 27 passengers and injuring 34.

What became known as the worst school bus crash in U.S. history led to numerous safety changes in Kentucky school buses – among them, a prohibition on the use of spark-ignited engines like the one that erupted in flames that night. The National Transportation Safety Board cited “fuel system integrity of school buses” as a safety issue that contributed to the accident.

Since then, for 25 years, diesel has powered all school buses throughout Kentucky.

Until this fall.

A case for propane

In an effort to improve efficiency, save fuel costs and be more environmentally friendly, Crittenden County School District lobbied for and won commonwealth approval to try a propane-fueled school bus in its fleet. It is the first spark-ignited engine in a Kentucky school bus since the 1988 accident.

Rachel Yarbrough, superintendent of Crittenden County Schools, some 240 miles west of the accident site, says the conversation began because she wanted to improve efficiency throughout the district, including the energy used to transport the district’s 1,300 students. With 35 buses traveling 298,000 miles a year, diesel costs were significant.

“We take very seriously the stewardship we have of our resources,” Yarbrough says. “We have tried our best to look at every single area where we can be more efficient to maintain a high-quality learning experience for the students of Crittenden County. If you really want to be efficient, you have to … be willing to consider alternatives outside what you’re currently doing.”

Living in the rolling hills of Kentucky, residents and district officials were familiar with propane, which is commonly used to heat their homes and readily available. They also took note of its sharply decreased price compared with diesel.

Wayne Winters, the district’s lead vehicle mechanic, was willing to consider alternative fuels. He conducted research, then assembled a committee to study the feasibility of propane.

“May 14, 1988, definitely changed student transportation in the state of Kentucky forever,” Winters says. “I would daresay Kentucky is the strictest in the nation with the safety of the buses. Even the thoughts of a propane bus [raise concerns] of fire and explosions, so the first thing I did was look at safety.”

What he found was a decades-old track record of safe, propane-fueled, spark-ignition buses in school districts around the country, including in Arizona, Illinois, Missouri, Oregon and California.

Once he was satisfied with its safety, Winters was impressed with how clean-burning propane is, with low emissions. That’s important for a vehicle that spends a lot of its time idling outside of schools and near children with growing lungs.

“The engine stays clean. The exhaust stays really, really clean, with no soot buildup,” he says. “It’s just so much cleaner than the old diesel engines, or even the new diesel engines.”

Changing policy

With the committee’s support, Winters approached the Kentucky Department of Education (KDE) about changing its policy. It wasn’t easy.

“It didn’t go very well at first,” he acknowledges. “It took us six to eight months to get a conversation going on a propane bus.”

Eventually, he presented a proposal to Kentucky Department of Education board members July 26, 2012, and with Winters’ persistence, research and enthusiasm, they were persuaded.

“I think the more KDE looked at it, they knew it wasn’t a matter of if but when they brought it to Kentucky,” he says.

By Sept. 27 last year, Crittenden County received notification that it could pilot the first propane-powered bus. On March 6, the district received an $80,000 grant from the Kentucky Division for Air Quality to reduce diesel emissions from its bus fleet. The funds were made available through the federal Environmental Protection Agency’s Diesel Emission Reduction Act.

The grant helped the district replace a 1992 model diesel bus with a $95,000, 2014 Blue Bird Propane Vision bus. It also retrofitted 14 other diesel buses in its fleet with emission-control technologies to reduce tailpipe emissions of particulate matter by nearly 50 percent with closed-crankcase ventilation systems.

River Region Propane, a division of United Propane Gas, installed a refueling tank on district property at no cost to the district except for pouring the concrete pad. The district locked in a yearlong price of $1.28 per gallon – compared with $4 per gallon of diesel.

Andy Keister, plant manager of River Region Propane, says he is happy to partner with Crittenden County Schools to supply its propane. Not only does autogas provide a good opportunity for retailers like him, whose business across nine counties is 85 percent residential homeowner heat, it helps the schools and keeps money in the community.

“It’s really good all the way around for everybody,” Keister says. “I felt all along this was something we should do.”

Winters is pleased with the use of propane in his fleet for several reasons:

Less expensive fuel. Fuel costs will be at least 50 percent lower for this propane-fueled bus than its diesel counterparts. So far this school year, the bus has traveled 1,332 miles at a cost of 23 cents per mile for fuel, compared with 50 to 52 cents per mile for the diesel buses. The propane bus is getting about 4.8 miles per gallon, but Winters expects that to improve to 6.5 or even 7 miles per gallon after it “breaks in.” It will cost the district about $8,100 to run each diesel bus the average distance of 16,000 miles this school year, compared with $3,680 for the propane bus, he says.

Cheaper oil changes. Winters says the district spends $384 per year on oil changes for the diesel buses. He expects to spend just $79.62 a year for the propane bus because it holds less oil and filters cost less.

Reduced dependence on foreign oil. “I wish we could buy everything we do here in Crittenden County so the money circulates here,” Winters says. “Or at least stay in the state, and then at least within the United States. The more resources we can use locally, the better it is for everybody.”

Fewer emissions. Cleaner-burning engines keep Kentucky green and the children healthy.

And this could be just the beginning. Winters expects state agencies will soon begin turning to propane autogas-fueled vehicles, and more school districts will embrace the savings and other benefits.

Chuck Harvill, general manager of Tennessee and Kentucky operations for Central States Bus Sales in Lebanon, Tenn., who sold the bus, says he already has fielded calls from three or four Kentucky school districts interested in knowing more. One wants to replace 14 or 15 buses, Harvill says.

More time needed
Enthusiasm for the return of a spark-ignited engine is tempered, though, in Hardin County Schools, where most of the teens who died in the 1988 accident had attended school.

John Skaggs, the district’s transportation director, had coached several of the teens in basketball and softball, and he knew siblings of many of the others who died.

Skaggs says he knows buses have had many safety enhancements since then. He’s intrigued by the potential savings.

“We’re going to watch pretty closely how they turn out [in Crittenden],” Skaggs says. “We do have some concerns. We’ll let them go through the year and look at the safety a little more before we’d even think about ordering one.”

Although the bus was not from the Hardin County Schools, the community suffered greatly. One of the teens who survived the accident now is on Skaggs’ staff as a driver, and he speaks every year to the students on the accident’s anniversary. The high school where many of the victims had attended school is adjacent to the cemetery where they are buried. A large, granite memorial at North Hardin Memorial Gardens in Radcliff honors those who died.

“We’re kind of wait-and-see right now,” Skaggs says. “Everyone’s kind of excited about the fuel savings, but also there’s the other side of the coin.”

Yarbrough says the time was right for the commonwealth to reconsider its ban on spark-ignited engines in school buses. In the 25 years since the accident, technology has advanced and the safety of propane buses has been proved in other states, giving Kentucky officials enough research to consider before approving the pilot.

“For KDE to take a chance on cracking the door for a pilot propane bus is, in some ways, remarkable, even though there is this overwhelming evidence of their safety ratings and account after account of school districts that have used them over time,” she says. “Had we approached KDE three years after the bus accident, there would have been no way.

“But enough time has passed, enough quality research [has been conducted] where propane buses have been used in a very safe way, and it’s taken this much time for those individuals to even crack the door to being open to a pilot for a propane-fueled school bus.”

SIDEBAR: The school bus market

ICF International is forecasting strong growth for propane in the school bus market, from about 20 million gallons in 2012 to more than 200 million gallons by 2020, says Mike Sloan, principal at the Virginia-based energy firm. Propane currently holds about 20 to 25 percent of the school bus market, seeing 6,000 to 8,000 unit sales per year out of a market of 25,000 to 30,000, Sloan says. Blue Bird, Thomas Built and Collins offer propane-fueled school buses.

SIDEBAR: The case for propane-fueled buses

With the launch of its pilot program, Kentucky joins a growing number of states that are turning to propane autogas-fueled school buses.

When you compare the cost advantages of propane – on top of the environmental advantages – it’s easy to see why.

Chuck Harvill, general manager of Tennessee and Kentucky operations for Central States Bus Sales in Lebanon, Tenn., says it can cost $8,000 to $10,000 to convert a diesel bus to run on propane. But that initial investment is paid off in four to five years in fuel savings alone. Propane averages $1.50 per gallon, while diesel is averaging $4 a gallon.

“We believe in it,” Harvill says. “We believe that it’s cleaner, more efficient and definitely cheaper.”

Michael Taylor, director of autogas business development for the Propane Education & Research Council (PERC), acknowledges that a propane engine’s miles-per-gallon statistic will be about 15 percent lower than that of a diesel engine. But, especially when combined with a 50-cent tax credit for each gallon of the alternative fuel, the savings from lower maintenance costs and high performance makes up for it.

“Propane has evolved into the automotive fuel for today,” Taylor says. “We’re using current automotive technology, and it’s providing the performance and results that we need.”

A propane bus will last at least 15 years and 200,000 miles, Harvill says.

“We believe it’s longer because it’s so clean, there’s no carbon in the engine, service intervals can be longer, oil doesn’t break down and get as dirty, if at all,” he says. “We believe the engine will last every bit as long [as diesel], if not longer.”

And they’re not hard for mechanics to service. The buses come with a five-year warranty, during which time the local Ford dealer repairs them. And after that?

“The beauty of it is, it’s a very common engine platform,” Harvill explains.

Schools in Portland, Ore., have used propane buses in their fleets for 30 years, Taylor says, adding that PERC projects that 10 percent of all school buses purchased in the United States this year will run on propane. Mesa, Ariz., Public Schools has saved more than $4.43 million over five years with its 90 propane buses and hopes to convert its entire 517-bus fleet to propane autogas.

Brian Carney of Roush CleanTech, which makes the fuel system for Blue Bird, says sales have doubled every year since 2010 as vehicle owners come to appreciate the benefits of dedicated propane over diesel, gasoline or bi-fuel systems.

As school districts across the country look to reduce their operating expenses, many are turning to propane. Taylor says he gets several calls every week from schools asking about propane buses.

“They have learned real quick that they need to find a fuel that will reduce, No. 1, their operating cost,” he says.

“When you look at the price of fuel at the pump and what is required to maintain diesel engines today, it’s very expensive, and propane gives some relief,” he says.

“So if we can encourage a prospective customer to look beyond the initial purchase price conversion costs and the minor decrease in MPG performance and get them to look at lifecycle costs, it’s a no-brainer. And we’re seeing those costs come down.”

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