Do You Know the Difference Between Electric and Hydraulic Hybrids?
Caterpillar spent two years testing both electric and hydraulic hybrid technologies. Here’s why the fuel-efficient hydraulic hybrid was our technology of choice.
Electric: Field technicians would have needed new training to learn the unfamiliar electronics and battery storage system.
Hydraulic: The components are similar to standard machines, so technicians won’t skip a beat.
Electric: The best opportunity to conserve energy is when the arm swings between two points. At each one, the excavator has to brake, resulting in lost energy. An electric hybrid could have converted that energy and stored it in a capacitor but would have had to convert it back for use with the motor.
Hydraulic: In a hydraulic hybrid, the braking energy is stored as pressure in an accumulator. When the machine swings, it is aided by the stored pressure. No conversion needed.
Electric: An enhanced cooling system would have been required to remove heat from the electric components.
Hydraulic: The size of the cooling system is actually reduced because overall engine efficiency is higher.
TIME TO RECOUP COST
Electric: Up to eight years due to complex (and costly) systems.
Hydraulic: Can be as little as 12 months.