It will not be offered in markets outside of Japan until after the first quarter of 2009.
The 20 tonne PC200-8 Hybrid is powered by Komatsu’s Hybrid System, based around a newly developed electric motor to turn the upperstructure, a power-generation motor, a capacitor and a low-speed diesel engine.
In announcing the new excavator concept, Komatsu Ltd President and CEO Kunio Noji said the company had decided to introduce its first hybrid machine in what is its flagship line – its Dash 8 excavator range.
"As a leading supplier to the construction manufacturing industry, we are determined to meet the needs of the time by practically proposing innovative equipment designed to reduce environmental impacts, including CO2 reduction," Mr Noji said.
Compared with a standard PC200-8, Komatsu’s hybrid excavator typically achieves a 25% reduction in fuel consumption – but in certain applications, where the machine is primarily involved in digging and slewing operations (rather than travelling), fuel reductions of up to 40% have been recorded.
Komatsu’s proprietary Hybrid System converts energy generated when the upperstructure reduces speed while slewing, storing the energy in the capacitor, then using it to assist the engine via the power-generation motor when the engine accelerates.
All components of the Komatsu Hybrid System – with the exception of the capacitor cells – are designed and manufactured in-house by Komatsu, ensuring high reliability and durability.
The main difference between conventional excavators and Komatsu’s new hybrid machine include:
• An electric motor to turn the upperstructure, rather than a hydraulic motor, which also stores energy generated when the slewing action is braked, with the regenerated energy used to augment engine power – allowing the engine to be used at lower speeds with higher-efficiency combustion.
• Capacitors which can instantaneously and efficiently collect, store and discharge electrical power from the regenerated energy, assisting the diesel engine in accommodating an excavator’s need for dynamic and frequent bursts of power when carrying out excavation work.
• When the engine is at idle, it is run at "super low" speeds, further contributing to lower fuel consumption.
Between the beginning of June and March 31, 2009 Komatsu expects to sell 30 hybrid excavator units, all in Japan, before offering the concept in international markets.
In Japan, the new PC200-8 Hybrid is selling for 27 million yen (around $A270,000) – about a 20% premium compared with a conventional machine.
Sean Taylor, Komatsu Australia’s General Manager, Construction, said that while the new hybrid excavator is not available in Australia just yet, it is an example of the company’s technological leadership.
"Komatsu has led the industry for many years in the development innovative, fuel-efficient hydraulic systems, engines and electronic control systems," he said.
"Our release of the world’s first commercially available hybrid excavator is the latest example of our industry-leading technology and engineering.
"And in the development of this new-concept machine, Komatsu has maintained its philosophy of designing and manufacturing the major components in-house, ensuring full integration of all aspects of the machine, ensuring maximum reliability and performance," said Sean.
"In releasing the world’s first hybrid excavator, we are demonstrating our strong commitment reducing customers’ machine owning and operating costs – and also to making a real difference in reducing greenhouse gas emissions in the longer term," he said.