Be sure to enjoy the new article about flywheel hybrids here!
Hybrids got a lot of press when gas was $4 a gallon, but now that it is below $2, does anybody care? Well, Eaton does.
Eaton has been in the power, hydraulics, and automotive business for quite some time, quietly developing new technologies used in most cars, trucks, and heavy trucks today. Cheap? No. 100% Free. Trade stocks for free on Zecco.com. The Free Trading Community. www.zecco.com
As I have written previously in "Hybrid Hummer Hums," Eaton was a main supplier in the hydraulic units for that vehicle. In this article, I will discuss two Eaton implementation of hybrid technologies.
Parallel Hybrid System
The picture above graphically displays Eaton's Hydraulic Launch Assist system, a heavy vehicle (garbage truck) with a standard engine, and hydraulic system is supplemental power. It is designed to capture energy through regenerative braking, store it in hydraulic fluid, and then use it to "launch" the vehicle from a stop.
From Eaton's web site, "During acceleration, fluid in the high-pressure accumulator is metered out to drive the pump/motor as a motor. The system propels the vehicle by transmitting torque to the driveshaft." This system is able to work in either Economy or Performance mode. The difference being that engine doesn't perform acceleration until after the hydraulic system is spent in Economy mode, while in Performance mode, both the engine and hydraulic system work together. In either case, Eaton predicts a 20-30% fuel efficiency increase.
Series Hybrid System
A series hybrid varies from a parallel system in that, "... conventional transmission and driveline are replaced by the hybrid hydraulic powertrain and energy is transferred from the engine to the drive wheels through fluid power."
The series hybrid allows the engine, mated to a continuously variable transmission (CVT) to operate at optimum efficiency, while "energy is transferred from the engine to the drive wheels through fluid power." This system also uses regenerative braking and managed engine cut-off to show fuel efficiency improvements of 50-70%. Would you feel better if you had more energy? Try FRS® Healthy Energy™ Free*!
Although these systems are not in full production, they are the leading edge in hybrid technology for heavy vehicles. Think about these hybrid systems when you see a city bus or garbage truck accelerate from a stop. Imagine seeing that same bus accelerate, but without that black cloud. That is progress.