Californian utility, Pacific Gas and Electric Company has purchased five Class 8 heavy-duty LNG trucks (Kenworth T800) for its alternative fuel fleet. According to David Meisel, director of transportation services at PG&E, "The Kenworth LNG-powered trucks will reduce greenhouse gas emissions by 15 to 20 percent over equivalent diesel engines."
These trucks actually use a bi-fuel system: The truck uses diesel to ignite the engine and then continues working with natural gas. This system is called High Pressure Direct Injection (HPDI). According to Kenworth and Westport Innovations, this systems allows the same torque and power as diesel engines, but has all the benefits of using natural gas (those lower emissions).
PG&E operates 36 natural gas fueling stations throughout its northern and central California service territory, 27 of which are open to the public. In addition, PG&E utilizes a mobile trailer mounted system for LNG vehicle fueling (manufactured by Chart Industries).
[Source: PG&E via NGV Global]