CHICAGO - Freightliner Custom Chassis Corporation (FCCC) introduced the newest addition to its robust alternative powertrain chassis development program - the pilot hydraulic hybrid walk-in van chassis. This latest alternative-fuel chassis from FCCC was launched at the recent National Truck Equipment Association (NTEA) Work Truck Show.

Boasting improved fuel economy and less brake wear due to regenerative braking, the hydraulic hybrid chassis is designed and engineered in partnership with Parker Hannifin Corporation to address environmental and cost-savings concerns.

"The hydraulic hybrid chassis not only offers a reduction in operating costs, it also decreases exhaust emissions, providing a substantial environmental benefit," said Jonathan Randall, director of sales and marketing for FCCC. "As the first chassis manufacturer to launch hybrids into the walk-in van market, we are very proud to continue that tradition by introducing our hydraulic hybrid as another option for

Predictions based on preliminary testing have shown that the hydraulic hybrid improves fuel economy between 50 to 70 percent over traditional diesel-powered vehicles with automatic transmissions in stop-and-go applications. The hydraulic hybrid improves fuel economy in three significant ways: recovered braking energy, improved engine efficiency, and its engine-off feature.

Built on the FCCC MT-55 chassis, the hydraulic hybrid system stores energy during the braking process in an accumulator. The energy stored in the accumulator is then used to accelerate the vehicle on the next launch. Upon reacceleration, the vehicle utilizes the energy stored in the accumulator and once depleted, the engine is restarted.

Another feature of the hydraulic system is that the engine is not connected to the rear wheels of the vehicle, allowing it to run more efficiently as it doesn't need to track road speed. Furthermore, the advanced engine-off feature allows the engine to turn off while idling at a stop. The engine only restarts when the energy stored in the accumulator is not enough to meet driving demands.

The hydraulic hybrid also requires less traditional friction braking because of its regenerative braking system, resulting in less brake wear and extended brake life. The regenerative braking system saves energy by recycling and storing it as hydraulic power, which can then be reused to propel the vehicle instead of losing it to heat as is the case with traditional brakes. The friction braking system is minimally used when the regenerative system is working, further extending brake life and lowering maintenance costs. 

FCCC and Parker Hannifin developed a prototype hybrid hydraulic chassis for FedEx Ground in 2008, and are currently running driver evaluation tests. UPS also received a hydraulic hybrid prototype for fleet testing.