Hydraulics can store energy but also become the transmission of vehicles that will be tested soon. Significant savings in energy are possible.
The Hybrid Truck Users Forum (HTUF), a government-corporate partnership led by CALSTART, has selected Hybra-Drive Systems LLC (HDS) to build three identical Class 6 hydraulic series hybrid delivery trucks for real-world testing by UPS, FedEx Ground and Purolator.
Under the new agreement, which is being funded by the Department of Energy, Hybra-Drive will build and deliver three hydraulic hybrid trucks over the next 9 to 12 months. UPS, FedEx Ground and Purolator then will each conduct a 6 to 9 month evaluation of the vehicle. Hybra-Drive anticipates that the evaluations will demonstrate up to a 60% cut in fuel use along with an accompanying reduction in emissions….
A hydraulic hybrid truck uses hydraulic pumps and hydraulic storage tanks to store energy, similar to what is done with electric motors and batteries in hybrid electric vehicles. Fuel economy is increased in three ways: vehicle braking energy is recovered that normally is wasted; the engine is operated more efficiently; and the engine can be shut off when stopped or decelerating….
The HDS Hydraulic Hybrid Power Train (HHPT) system combines a combustion engine with a hydraulic propulsion system that replaces the conventional drivetrain and transmission. The engine, fueled by gasoline, diesel or alternative fuel, operates a hydraulic pump that pressurizes the stored energy hydraulic system to propel the vehicle.
Check the graphic below to see how the system works. (click on graphic to enlarge) This is elegant in it’s simplicity and just another choice in the lineup of inventions to save energy.