New York City's Department of Sanitation and Baltimore's Bureau of Solid Waste will test hydrostatic regenerative brakes from Bosch Rexroth, Rochester Hills, Mich.
During braking, a hydraulic pump connected to the driveline captures kinetic energy. The pump absorbs energy from the driveline and slows the drivewheels. The absorbed energy sends hydraulic fluid into an accumulator. The incoming fluid compresses inert gas in the accumulator.
During acceleration, pressurized gas pushes fluid out of the accumulator. The pump now acts as a hydraulic motor, assisting the engine and reducing the fuel required to accelerate the vehicle.
The project’s goal is to promote the widespread adoption of hydraulic hybrid powertrains in vehicle fleets.