It took some time to develop the parts for the Prius so it's understandable that Toyota needed equal time to develop special forklift parts for the world's first internal combustion-electric hybrid lift truck. An IC-electric hybrid forklift is not a simple matter of putting two systems side by side in the same vehicle. Adjustments are needed to derive optimum performance from both the internal-combustion engine and the electric motor, and then make them work automatically with each other.
How the IC-electric hybrid works
The two sources of power in a hybrid can be combined in different ways. One, a Parallel Hybrid has the fuel tank that supplies diesel to the engine, and the battery that supplies power to the electric motor. Both can simultaneously turn the transmission which turns the wheels and lifts the load. In the other type, a Series Hybrid, the engine does not directly power the transmission. Instead, it turns a generator which powers the battery or the electric motor. The electric motor then turns the transmission. In some forklifts, a Series system is used for driving and a Parallel system for loading.
The hybrid forklift has a diesel engine that is smaller than usual and engineered for minimum CO2 emissions. A hybrid has a very advanced electric motor with sophisticated electronic systems that enable it to act as a motor and a generator. It draws energy from and returns energy to the battery. The transmission in a hybrid works much like the transmission of a normal diesel forklift.
Major IC-electric hybrid launches
Launched in December 2009, the Toyota Geneo-Hybrid is a 3.5 ton counterbalanced forklift. It combines a 2.5 liter diesel engine with a 26-kilowatt electric motor and a nickel-hydride battery. It is said to reduce fuel consumption and CO2 emissions by 50%. The truck uses a Series Hybrid system for driving and a Parallel Hybrid system for handling loads. The litter receives mechanical energy from the diesel engine and generator, and electric energy from the battery. The battery does not need to be plugged in for recharging but is recharged by the engine's operation.
Since then, other companies have developed IC-electric hybrid forklifts. Mitsubishi Heavy Industries released a 4 – 5 ton hybrid forklift in 2011. It boasts of a unique powertrain design with a lithium-ion battery, a low-emission diesel engine, two induction motors and an inverter. Komatsu introduced a 2-ton lift truck that has reduced the number of major forklift parts by over 30%. It claims a reduction of 20% in fuel consumption and CO2 emissions. Proton Power Systems plc launched a triple-hybrid forklift which combines a fuel cell, battery and supercapacitors that result in 50% energy savings. Anhui Heli Company exhibited a 7-ton hybrid forklift with a lead-acid battery and supercapacitors, the first industrial hybrid vehicle in China. Kipor of South Africa produces a 3.5-ton hybrid forklift.
The IC-electric hybrid forklift is a relatively recent development. For this reason, forklift parts directly related to its hybrid nature are available only from manufacturers. As the hybrids become more common, however, you can expect that a sufficient supply of aftermarket forklift parts for hybrids will become available.