Greener Garbage Trucks

Nikki Chandler Contributing Editor Kansas City, Kan.

GARBAGE TRUCKS USED to be the oldest, least fuel-efficient and most polluting vehicles on the road. But according to a recent study, “Greening Garbage Trucks: New Technologies for Cleaner Air,” a shift is occurring as fleet operators in the United States move from diesel to compressed natural gas (CNG) or liquefied natural gas (LNG). Some companies or municipalities even are testing hybrid electric technology.

In its report, New York-based Inform, an independent research organization, profiled 19 companies in the United States, Japan and the Netherlands that have tested and deployed new garbage truck technologies and alternative fuels. The organization found that while more than 90 percent of garbage trucks are powered by traditional diesel engines, several waste collection agencies are leading the transition from diesel fuel to natural gas-powered trucks.

Fleet managers primarily were motivated to switch to natural gas trucks to meet environmental regulations, according to Inform. For example, Los Angeles and Corona, Calif., both cited the Diamond Bar, Calif.-based South Coast Air Quality Management District's (SCAQMD) Rule 1193 as their reason for going green. The rule requires refuse haulers that own 50 trucks or more to purchase alternative fuel vehicles when adding to or replacing their fleets.

However, other companies also were encouraged to switch to natural gas because of costs. The lower cost of natural gas, tax incentives, grant programs and bid specifications that give preference to companies that operate natural gas vehicles can make alternative fueled fleets more economically feasible. For example, Houston-based Waste Management Inc. decided to use an alternative fueled fleet in San Diego because it generated marketable air pollution credits. The emissions credits then were sold to another company for a proposed power plant project.

Additional benefits of alternative fuels include a reduced dependence on foreign oil, which primarily is obtained from Middle East. Also, air pollution is significantly reduced. According to the report, emission reductions range from 67 percent to 94 percent with particulate matter; 32 percent to 73 percent with nitrogen oxide; and 69 percent to 83 percent with nonmethane hydrocarbon. Other advantages include improved water quality, fewer greenhouse gases and a reduction in noise levels, the report states.

Nevertheless, the No. 1 obstacle preventing fleets from transitioning to natural gas is the high cost. In the U.S. fleets Inform studied, the price of a natural gas truck ranged from $210,000 to $250,000, approximately 15 percent to 25 percent higher than the cost of a comparable diesel truck.

“It is important to note that purchasing new trucks is not the only way to shift to natural gas,” says Juliet Burdelski, contributing author and director of Urban Outreach for Inform. Trucks that burn diesel fuel can be repowered by replacing the diesel engine with a natural gas one.

Retrofitting an existing truck ranges from $30,000 to $100,000. “Repowering an existing truck costs less than replacing the vehicle, but the total cost — purchase price of a diesel vehicle plus cost of retrofit — will likely be greater than the purchase price of a new natural gas garbage truck,” Burdelski says.

Overall, the report states, the cost of shifting a refuse fleet to natural gas varies depending on factors such as refueling infrastructure options, truck maintenance costs, facility requirements, local safety codes, labor and training costs, fuel cost and available economic incentives.

Inform found that another hindrance preventing fleet managers from changing fuels is their perception that natural gas trucks are not as safe as diesel. However, CNG tanks have proven durability. From 1990 to 1993, 300 LNG trucks traveled 6 million to 8 million miles and had only four collisions. Moreover, the fuel systems sustained little damage in the accidents, Inform states. By 2010, Inform projects that more than 2,200 natural gas garbage trucks — or 1.2 percent of the total U.S. fleet — will have been deployed, displacing approximately 476,000 barrels of oil annually.

Countries such as Spain, Mexico, the Netherlands and Japan, are operating natural gas trucks, and the “global trends mirror those in the United States,” Inform says. Therefore, the more strides America takes to reduce its oil consumption, the sooner other countries will as well, the nonprofit predicts.

Inform offers the following tips to fleet managers ready to adopt greener garbage trucks: