The first vehicle has been delivered to the Waste Management facility in El Cajon, Calif., where the giant refuse hauler announced that the company has joined forces with PG&E Corp. to establish a program that will use emission reductions gained from the vehicles to pave the way for construction of a power plant in San Diego County. This is the first time that emission reductions from mobile sources have been used to offset emissions from a major stationary source.
The vehicles will be equipped with the new 12-liter Mack Eco-Tech engine. With 325 horsepower and 1,050 pounds-feet of torque at 1,250 RPM, these engines feature a spark-ignited design and operate on either liquefied or compressed natural gas (LNG or CNG). In order to meet the stringent emissions requirements requested by Waste Management, the engines had to meet an EPA-certified NOx emissions level of 2.0 grams per brake horsepower-hour (g/BHP-hr), which is 20 percent below the EPA requirement that will go into effect in 2002.
A total of 30 Mack LNG-powered vehicles will be delivered through this year, with Waste Management agreeing to purchase another 90 vehicles over the next two years.
Freeman added that the engines also are electronically controlled and feature clean, quiet operation and maximum fuel economy, while running reliably at high operating temperatures typical in trucks that travel at low speed for extended periods.
The control system of the 12-liter Mack Eco-Tech engine, engineered specifically to accommodate the use of natural gas, consists of newly designed head and valve covers to incorporate centrally located spark plugs.
When integrated into the Mack MR and LE chassis, the engine is fueled by two LNG tanks that are mounted on each side of the truck -- one holding 100 gallons and the other holding 50 gallons. Waste Management also has the option to order a single LNG fuel tank that would be mounted to the left rail and store 150 gallons of fuel.
(For more information, see "Waste Management Gets Great Deal on Clean Trucks."