Optonics Underground Factory

Minokamo, Japan

The World's First Underground Eco-Factory for Manufacturing

The Optonics Underground Factory is the first Eco-Factory built below ground for the manufacture of machine tools. The 293,000 square foot facility is located 36 feet below ground in Minokamo, Japan and is dedicated to the production of Mazak's high-speed, precision laser-cutting machines. 

Benefits of Being Below Ground 


Free from contaminants, Mazak's machines are able to reach a peak level of precision. Isolation from the outside environment gives the facility 30 times better air quality than typical manufacturing facilities. 1.77 million cubic feet of air is replaced hourly through the plant's air filtration system, resulting in a dramtic decrease in dust particles. Being underground also allows for virtually no external vibration or fluctuation in temperature which could affect the fit and function of the machines.  

Environmental Friendliness

In land-starved Japan, it is important to maximize the use of space. The Optonics Underground Factory uses nearly 100 percent of the land set aside for the facility while still aiding the environment as grass and trees grow atop. Also, by using natural geothermal energy, the factory minimizes its carbon footprint and reliance on external energy sources.