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raised floor

An elevated floor used in datacenters and laboratory facilities that allows wires to be run underneath. A raised floor is also used to distribute cooling. There are many varieties; however, the traditional raised floor uses square tiles over an aluminum grid that creates a plenum (space) several inches above the actual floor. Each tile can typically be lifted up and out for access to the cables below. Although raised floors are commonly used for datacenter cooling, a unique alternative eliminates the raised floor (see KyotoCooling).

The Traditional Raised Floor
This type of raised floor has been the standard in datacenters for decades. The structural grid is spread out over the original floor, which allows flexibility in the initial equipment installation as well as future changes. (Image courtesy of Imprint Data Center Solutions,


A water-free datacenter cooling system from KyotoCooling ( that uses a rotating heat exchanger wheel that resides above the equipment floor. The rising hot air from the servers is absorbed in the wheel, which is cooled with outside air. The cooler air is sent back down to the servers.

Commonly used in combination with traditional air conditioning (DX compressors), which can be idle as much as 75% of the year depending on geographic location, KyotoCooling saves water and power. In addition, KyotoCooling datacenters can have equipment on cement floors rather than raised floors, allowing taller, heavier equipment racks to occupy the same footprint. See rack mounted and datacenter.

The KyotoCooling System
A massive, spinning corrugated aluminum wheel (the KyotoWheel) is cooled with outside air in one plenum while it absorbs the heat from the server racks in another.

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