Hydraulic Hybrids Promise Economy Gains

Eaton Corporation is said to be developing a new hydraulic hybrid powertrain technology
that was a result of a joint project with the Environmental Protection Agency. A diesel
engine with a hydraulic propulsion system replaces a conventional drivetrain. The truck
uses hydraulic pumps and storage tanks to develop and store pressurized fluid. Fuel economy
is increased when braking energy is recovered, when the engine is operated more efficiently
and when the engine is shutoff when stopped or decelerating. The Eaton technology, which
promises major fuel savings and environmental benefits, was tested in cooperation with UPS.
Tests show a 45-50% gain in fuel economy compared to a conventional diesel truck and UPS
says similar fuel economy gains along with a 30% reduction in CO2 emissions are possible.