There were a lot of nervous people around the maintenance garage at SunLine Transit Agency back in May of 1994. That's when the Agency, serving a population of over 350,000 people in 11 Southern California cities, sidelined its entire fleet of diesel transit buses and—overnight, literally—started running entirely on compressed natural gas (CNG) buses.
"One day they all just came rolling up into the yard, and we were all in awe," recalls Ed Gallardo, maintenance manager for SunLine. "It was 34 brand new Orion buses, and the only introduction we had to CNG at that time was sitting in a classroom and learning about natural gas. So to actually see and be able to operate one of those vehicles was a little bit intimidating."
"The conversion to CNG was extremely aggressive," admits general manager Mike Oglesby, "and there was a little bit of luck involved. I have converted fleets during my time in transit and you always want to have a backup plan, so to put two feet in the water was aggressive."
THE SPIRIT OF A TEST FLEET
What began 11 years ago with an abrupt decision by the Agency's forward-thinking Board of Directors to convert the entire fleet to alternative fuels has ended up transforming SunLine into one of the best-known test fleets in the country. Every day that this fleet is in service, it is running one test bus or another in revenue service up and down the hot, dusty roads and highways of Coachella Valley. The result is a maintenance department that can handle virtually any new technology that management can put on the road.
"Looking back, I wouldn't do it any other way," director of maintenance Tommy Edwards recalls of the CNG switchover 11 years ago. "In fact, when we switched to CNG, I argued that we should phase it in, but the upper management decided to do it overnight. Now that we've done it, I think that's a great way to do that kind of new technology."
Indeed, the window to Edwards' office overlooking the maintenance garage in Thousand Palms reads 'Today's technicians for tomorrow's world,' a slogan that sums up Edwards' approach to new technology. "I like to think that there's not much these guys can't get a hold of and start working on," he says.
THE FIRST ENGINES
Today, SunLine is testing a $3.1 million hydrogen fuel cell hybrid bus, but this new project is one in a long line of tests that began with those early CNG engines. According to Edwards, his predecessor at SunLine was approached by Cummins Diesel to test their first CNG engines, conversions of the existing L-10.
"They came to SunLine and said, 'Hey, let's put a couple of these engines in your buses,' and my predecessor thought, 'Well, if I get two new free engines, that gives me two spare engines,'" Edwards recalls. "That's how he got it started, and it's just snowballed from there."
As associate engineer Apollonia "Polo" del Toro recalls, those first L-10 CNG conversions actually played to the strengths of the maintenance crew.
"What changed was they re-engineered the head to take spark plugs, they hardened some of the exhaust and intake valves, they changed the seat and the piston configuration," he recalls. "So the crossover from diesel to CNG wasn't as dramatic for some of the people who had already seen the L-10.
"The gas guys and the diesel guys learned from each other," he continues. "The diesel guys were used to compression ignition, but on CNG you have to have a spark plug, so we were able to learn from the people who worked on automotive, because they're used to stoichiometric stuff, they're used to running lambda, but they're not used to the big engine. The diesel guys were used to the big engines, so together we learned from each other."
NO SECOND CHANCES
"There were a lot of people saying 'They're never going to make it. It's impossible,'" says del Toro. "We couldn't fail; our old buses were auctioned off fairly quickly, so there was no emergency fleet we could put out there. It was swim or sink, and we all like to breathe, so we did what we had to, to learn what we needed to, to keep the buses on the road."
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