CHICAGO, Ill. – Freightliner Custom Chassis (FCC) has a hydraulic hybrid walk-in van chassis at the National Truck Equipment Association (NTEA) Work Truck Show. Boasting improved fuel economy and less brake wear thanks to regenerative braking, FCC announced the hydraulic hybrid chassis is designed and engineered in partnership with Parker Hannifin 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 FCC. “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 customers.”

The new hydraulic hybrid can improve fuel economy 50-70%, over traditional diesel-powered vehicles with automatic transmissions in stop-and-go applications, according to the company. The hydraulic hybrid is designed to improve fuel economy in three ways: by recovering braking energy; improving engine efficiency; and by powering off the engine when stopped.

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

“The hydraulic hybrid is able to recover and re-use about 70% of the energy that otherwise would have been wasted during the braking process,” said Rich Kimpel, engineering manager for the Parker Hydraulic Group Technology and Commercialization Support Team. “On the other hand, typical electric hybrids can only recapture about 25% of the brake energy.”

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, adds the chassis manufacturer. FCC adds the advanced engine-off feature is designed to allow 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 demands.

“The hydraulic hybrid differs from a hybrid-electric vehicle because the accumulators recharge much faster than batteries while the overall hydraulic system offers nearly 10 times the power density of electric hybrids,” Kimpel said. “This factor also contributes to improved fuel economy by allowing the capture of more brake energy.”