Home Latest News STN EXPO Workshop Discusses How Alt Fuels Can Save Maintenance Dollars
STN EXPO Workshop Discusses How Alt Fuels Can Save Maintenance Dollars PDF Print E-mail
Written by Ryan Gray   
Wednesday, 30 July 2014 11:39

Three student transportation professionals shared their experiences with alternative fuels and how they are changing operations and costs in the maintenance garage during an STN EXPO breakout session on Monday.

STN EXPO Co-Chair Ralph Knight, the director of transportation at Napa Unified School District in Northern California, led the discussion. Knight is an award-winning fleet manager for his early adoption of alternative fuels. California has mandated that school districts, as well as other fleets, only purchase new vehicles that are powered by alternative energy, and Napa Valley has been a leader in embracing a wide range of options from CNG to propane to electric to hybrids.

That was evident by the information Knight shared on his experiences over the past two decades as well as similar data on maintenance savings from the Los Angeles Unified School District and Houston Independent School District.

Mark Swackhamer, the senior fleet operations manager at Houston ISD, discussed his experience with propane as well as B5 biodiesel for use with the district’s ultra-low- sulfur diesel school buses. Swackhamer said the propane buses are getting between 4.5 and 5 mpg but are saving considerable money in the shop. He explained that preventive maintenance costs about $35 per bus compared to $95 for diesel at the same 6,000-mile interval, mainly due to propane requiring less oil and, as a result, fewer oil filter changes as well as fuel filters.

All told, Swackhamer said propane is saving the district $3,000 per bus per year in fuel and maintenance costs. Propane also costs half the price of diesel while providing more power.

“Propane is absolutely the best way to go,” for Houston, he added.

He forecasts that propane-powered engines will last a similar 250,000-mile life as diesel engines and a “worst-case scenario” that Houston will break even on propane. The district mainly relies on taxpayer money to buy and operate the propane buses.

He noted his one regret is that he wishes he would have installed two 18,000-gallon propane tanks at the district’s maintenance facility to keep a larger supply on hand between deliveries.

Meanwhile, Swackhamer reported that within six to eight months of switching over to B5 biodiesel, fuel filters were completely unclogged because necessary lubricity was reintroduced that had been absent in regular ULSD. B5 has also offset the 105,000 gallons of diesel that Houston would have otherwise needed to purchase.

Knight and Donald Wilkes, director of transportation at Los Angeles Unified, then talked about CNG.

“The first years were really challenging,” Knight said. “Everyone kept the (engine) information so secret, all the manufacturers did. (But) we’re no longer what you’d call fearful of alternative fuels.”

Today, CNG as well as propane result in longer oil life, they agreed. Knight said oil in CNG buses “comes out as clean as it goes in.” He also said fuel costs have been cut in half compared to diesel.

Wilkes said nearly two-thirds of LAUSD’s school buses are powered by alt fuels such as CNG, LNG and propane. The district began running CNG buses in 1991, and today’s CNG buses “run extremely well," he added.

The most expensive part of CNG is the infrastructure, he said, as maintenance facilities need ventilation systems and alarms in case of a leak. But, as with propane, CNG quickly rises and evaporates. Wilkes said he also likes the continuous flow of CNG from the pipeline, whereas propane needs to be delivered regularly.

“At the end of the day, ultimately you need to look at the environment and see what’s right for the operation,” he concluded. “Taxpayers are willing to pay for alternative fuels."

Last Updated on Wednesday, 30 July 2014 11:56