While hybrid trucks are in their infancy, they show significant potential from a fuel economy and environmental perspective. “Customers and regional authorities are looking for fuel-efficient, environmental-friendly solutions. The new Kenworth T270 hybrid vehicle offers the benefits of reduced fuel use as well as the civic impact of responsible environmental practices,” said Bob Christensen, Kenworth general manager and PACCAR vice president. Kenworth will have limited production of medium duty hybrid trucks for municipal fleets and utility companies this year with full-scale production expected to follow in 2008, according to Christensen. The Kenworth T270 Class 6 hybrid medium duty conventional is powered by the new PACCAR PX-6 engine and features an integral transmission-mounted motor/generator, a frame-mounted 340-volt battery pack, and a dedicated power management system. “During steady driving conditions above 30 mph, the T270 hybrid operates like a standard diesel vehicle with all power coming from the engine,” said Mike Dozier, Kenworth chief engineer. “Below 30 mph, it uses a combination of diesel and electricity. The system automatically switches between the two modes of operation and is seamless to the driver.” The goal for the T270 hybrid is to improve fuel economy by 30% in start-and-stop applications, such as utility trucks and pick-up and delivery. “The more stop-and-go in the application, the better the truck’s performance,” said Dozier. The Kenworth hybrid uses braking events to generate and store electricity. The process is called regenerative braking. “That electrical power is then used for acceleration, assisting the diesel engine,” said Dozier. “As a bonus, there’s a reduction in brake wear since the generator produces braking energy.” For medium-duty applications, such as for utility work, the T270 hybrid can be spec’d with an electric power-take-off (PTO). “A PTO can be powered using electric power. As the battery charge is depleted, the engine will automatically restart and recharge the battery in less than five minutes,” said Dozier. “This is an excellent benefit, especially for utility customers who need to power buckets. Plus there’s no noise with electricity, a big consideration when working in urban and residential areas.”