Komatsu Introduces the World’s First Hydraulic Excavator: Hybrid Evolution Plan for Construction Equipment

Komatsu Ltd. (President & CEO: Kunio Noji) announced today that the Company is going to launch sales of the PC200-8 Hybrid excavator, the world’s first hybrid construction equipment. (*1)
The PC200-8 Hybrid is powered by the Komatsu Hybrid System which uses a newly developed electric motor which turns the upper structure, power generation motor, capacitor and diesel engine. Compared with the standard PC200-8 hydraulic excavator, the hybrid model achieves about 25% reduction of fuel consumption. (*2)
Earlier in May 2007, Komatsu launched the world’s first hybrid electric forklift trucks on the market. We are introducing this hybrid excavator as it is our flagship construction equipment.
As a leading company of the construction equipment manufacturing industry, we are determined to meet the needs of the time by practically proposing innovative equipment designed to reduce environmental impact, including CO2 reduction.

1. Fuel Economy

Compared to the standard PC200-8, we have achieved an average of 25% reduction in fuel consumption. (*3) Furthermore, in the operation tests by customers, we have confirmed the maximum reduction of 41% at a jobsite where the machine’s upper structure turns more frequently.



* Notes
1. Based on our research on seven major products (crawler-type hydraulic excavator, wheel-type hydraulic excavator, wheel loader, bulldozer, rigid-type dump truck, articulated dump truck and motor grader as of May 13, 2008.
2. This figure varies depending on the nature of work.
3. Computed according to our internal-use standard concerning average ways of using construction equipment.

2. Outline of the Komatsu Hybrid System

Our proprietary Komatsu Hybrid System converts energy generated when the upper structure reduces its speed while turning, stores the energy in the capacitor, and uses it to assist the power of the engine via the power generation motor when the engine accelerates.



All components of the Komatsu Hybrid System are made in-house , ensuring high reliability and durability.(*4)

* Note 4.Excluding capacitor cells.

3. Major Characteristics of the PC200-8 Hybrid when Compared to Standard Construction Equipment and Hybrid Cars

1) Comparison with Standard Construction Equipment
While standard equipment normally uses a hydraulic motor to turn the upper structure, for this movement, Komatsu has newly developed an electric motor for the Hybrid. By using this electric motor which collects energy generated when the upper structure’s turns slow down, we have achieved a hybrid excavator.
While standard construction equipment uses only diesel engines for power, our new hybrid excavator utilizes regenerated energy to assist the engine when it is accelerating, enabling the use of the engine in a low revolution zone with high-efficiency combustion. In addition, while the engine runs idle, our hybrid excavator keeps the revolution at a super low level, achieving impressive reductions in fuel consumption.

2) Comparison with Hybrid Cars
Hybrid cars require a large amount of electric energy when they start moving and accelerating, then they can run with relatively stable engine revolution. By comparison, construction equipment has to accommodate dynamic and frequent fluctuations of the engine revolution, for example, for excavation work. To assist the engine for such fluctuations, the PC200-8 Hybrid is mounted with a capacitor.
Automotive batteries work on the principle of chemical reactions, thus it takes time for them to discharge electricity, lacking sufficient support when applied to construction equipment. Meanwhile, capacitors can instantaneously and efficiently collect, store and discharge electricity.