“Before building a CNG fueling station or converting a fleet to run on natural gas, it is important for transit agencies to understand how upfront infrastructure costs can be offset by fuel cost savings and investing in quality equipment and service,” says Trillium Director of Market Services Jennifer de Tapia. “CNG fuel costs are often far less than diesel; fuel savings of two dollars per gallon are very common among CNG users.”
Based upon the last four months of data, Valley Metro RPTA Fleet and Facility Program supervisor provided the following: The CNG costs per mile show an average of 44 percent less than diesel and that the current CNG maintenance costs per bus average is $.63 cents per mile and the diesel bus maintenance costs average $.76 cents per mile.
Jack Dooley, director of maintenance for Omnitrans, says that the cost of the fuel at delivery is less than the diesel fuel costs in California. “However, bottom line costs are higher because of infrastructure maintenance costs.” He says that the LNG stations cost Omnitrans about $5.3 million plus the annual maintenance contract of $300,000 per year. “The diesel side of this cost us less than $5,000 per year.” He adds, “If Omnitrans utilized pipeline natural gas instead of LNG, it would likely reduce the cost differential substantially. We switched from pipeline gas to LNG in 2004 due to odor complains from the residents surrounding our main facility.”
De Tapia says that beyond fuel costs, there are other ways to maximize investment in CNG technology, such as designing station equipment for long-term, efficient operation.
“During a procurement, agencies should establish performance-based specifications for station design based on the fueling requirements of their fleets,” says de Tapia. “This will allow CNG contractors to design the ideal fueling system based on the number of buses, nightly fueling window and desired fill times.
“Agencies should employ flexible evaluation criteria that take into account innovative station designs and technologies. “ She adds, “Station designs that optimize fueling system efficiency will be capable of generating considerable long-term savings on everything from utility to maintenance costs.”
She also says, “Too many agencies have replaced their equipment after less than 10 years of use. Your investment should last at least twice that long.” She adds, “Installing quality equipment and maintaining it properly will provide the most cost-effective fueling solution over the long term.”
Running on CNG
Omnitrans’ Dooley says a benefit of natural gas is its lack of toxicity as a raw fuel. “We no longer have to worry about soil contamination. It also is less hazardous than diesel fuel because of its physical characteristics: lighter than air in its gaseous state and does not pool like liquid fuels.”
The Fort Worth Transportation Authority (The T) President/Executive Director Dick Ruddell says he can’t say enough about the benefits of a natural gas bus fleet. “It is less expensive compared to diesel, the maintenance is cleaner and more predictable, the engines are more reliable, and it improves bus operations efficiency because it requires fewer fill ups.” A single fueling will operate one of the buses for its full day’s run.
The greastest long-term benefit to a transit agency he says, is the environmental contribution and the positive impression that it creates about the agency for riders, residents, employees, government officials, the media and community leaders in the region.
“After previously operating other agency bus systems with smelly black fumes that cars and pedestrians didn’t want to be behind, it is so refreshing not to have those complaints,” Ruddell says. “Our employees feel proud of our “green” fleet and our mechanics like working without the fumes and smelly, dirty hands. Being perceived as “green” by operating a clean-burning fleet has given The T an image that it cares about the welfare of its community ...”
Wendy Williams, director of marketing for Omnitrans, says they have publicized their 100-percent CNG bus fleet through print ads and radio ads as part of the overall environmental benefit of transit use. “We have gotten related media coverage over the years,” Williams says. “Our board takes pride in the fact that we have a clean fuel fleet.” And she adds that due to local fleet regulations in California, diesel is not an option.