Reducing truck emissions

For several years, the Culver City, Calif., Sanitation Division has been replacing its diesel-powered refuse collection trucks with alternative fuel vehicles. This fall, the division is adding a rear-load refuse collection vehicle that runs on compressed natural gas (CNG). The truck is one of the first of its kind in the country and the city’s first rear-load collection vehicle in 18 years.

Air pollution is a big issue in California, including Culver City, a community of 40,000 residents outside of Los Angeles. To reduce emissions from work trucks in the Los Angeles Basin, the South Coast Air Quality Management District mandates that all new vehicles in the area with a gross vehicle weight of 14,000 pounds or greater must use alternative fuel.

Since 2002, Culver City has been buying CNG refuse vehicles to replace diesel refuse collection vehicles after eight years of service. Most of its routes use seven automated side loaders or eight front loaders — seven of which run on CNG — manufactured by Chattanooga, Tenn.-based Heil Environmental. However, some of the city’s large condominium complexes have narrow streets without enough clearance for the vehicles, so the city decided to purchase a small rear loader to collect refuse in those neighborhoods.

Culver City contracted with Monrovia, Calif.-based Bodyworks Equipment to purchase the 18-cubic-yard rear loader with CNG tanks mounted on the roof. To limit manual labor for the vehicle’s two-person crew, the truck body includes a hydraulic cart lifter, from Greenville, S.C.-based Bayne Premium Lift Systems, on the hopper to lift and empty the carts.

Some equipment buyers hesitate to buy alternative fuel vehicles because they cost more than diesel trucks. A CNG refuse collection vehicle, for example, may cost $20,000 to $35,000 more than its diesel counterpart (compared to non-2007 emission-compliant engines). Maintenance costs also are slightly higher. But Paul Condran, equipment maintenance manager for Culver City, says the benefits of CNG-powered vehicles outweigh the disadvantages. “We’d prefer running natural gas over anything volatile like gasoline,” he says. “It’s safer, and it’s as much as 60 percent cleaner. It’s readily available, reduces our dependency on oil, and it’s at least half the cost of [other] fossil fuels.”

The city’s transportation department operates its own CNG fueling station, as well as a standard fuel station. This summer, CNG cost $1.15 per gallon versus $2.55 per gallon for diesel. New ultra-low-sulfur diesel fuel was expected to add another 10 to 25 cents per gallon to the city’s diesel costs starting Sept. 1. Even though heavy-duty CNG vehicles use 10 to 15 percent more fuel than diesel vehicles, the cost difference still results in savings.

In Culver City’s experience, CNG vehicles perform as well and are as reliable as diesel-powered vehicles, Condran says. Because the engines in CNG vehicles remain cleaner, technicians prefer working on them. The CNG vehicles also run more quietly than diesel engines, so they are less disturbing when refuse crews collect early in the morning. “Our citizens enjoy the fact that the city uses natural gas,” Condran says. “You can’t really put a price on clean air.”