Propane Fleet Honored For Clean Air Leadership

(August 12, 2019) — When the San Diego Metropolitan Transit System (MTS; San Diego, Calif.) looked at alternative fuels to find a replacement for gasoline in its paratransit buses and minibuses, it determined that propane autogas provided the tank capacity and range those vehicles require.

Today, nearly three years after it began transitioning those fleets to propane,

MTS has found that the propane buses also operate cleaner and more economically.

“These buses are doing a lot for the environment in San Diego and Southern California,” Jay Washburn, manager of paratransit and minibus at MTS, told BPN. “They also allow us to be a good steward of taxpayer dollars by reducing costs.”

MTS was honored at the recent Advanced Clean Transportation (ACT) Expo with a Fleet Award that recognizes fleets that demonstrate leadership in clean transportation.

The agency began transitioning its paratransit buses and minibuses from gasoline to propane in fall 2016. As each gasoline bus comes to the end of its lifecycle, MTS replaces it with a new propane bus.

As of now, 107 of the agency’s 167 paratransit buses and 31 of its 37 minibuses are powered by propane. The propane versions of both buses came with a Ford 6.8L V10 gasoline engine and were converted to propane autogas by ROUSH CleanTech.

Washburn joined MTS in the summer of 2016. The decision had been made to test propane buses and he was then involved in determining whether they were a good and viable solution.

“We had to look at range, because some of these buses travel 300 miles per day,” he says. “The best tank capacity and range were provided by propane.”

Once these fleets have been fully converted, the CO2 and greenhouse gas emissions will be reduced by 11 metric tons per year, per vehicle. MTS has also found that the return on investment (ROI)—the savings on fuel cost versus the purchase price of the vehicle converted to propane—was recouped in three years. The vehicles have a six-year lifecycle. This ROI is based on wet hosing and can be reduced as low as 1.9 years with onsite large bulk tank fueling.

“We also watch for any increase in the amount of maintenance required or the number of breakdowns,” Washburn says. “We haven’t seen any negative trend. The propane buses have performed well in reliability and operability. Clients like them because there is less exhaust.”

MTS started the propane conversion with wet hosing. After about a year, the agency installed a 2000-gallon tank on site for fueling. The ROI could be even better if the agency were able to have a larger tank, because it would be able to buy the fuel more economically. The amount of fuel storage allowed onsite for refueling is limited by local Fire Department regulations. “To maximize fuel cost savings, we would need a 12,000-gallon tank on site to be able to take full tanker truck loads of propane,” Washburn explained.

Staff were trained on propane autogas vehicles by ROUSH CleanTech. “ROUSH brought in personnel to train our staff and they provided online training as well,” Washburn says. “It was a smooth transition.”