Data center cooling has traditionally been tackled one way. Air conditioning units (or CRACs) are placed around the outside wall of the room and aligned with the hot aisle. They then pump cold air underneath a raised floor for distribution in the cold aisle. While this method is generally considered an effective technique, it has a big limitation. It makes air travel long distances through open spaces between the CRAC and the equipment needing cooling. This contributes to inefficiency.
Current developments in the data center air conditioning field center around limiting the distance that air has to travel and confining the space in which it is traveling. The goal is to prevent hot and cold air mixing and limit the amount of energy needed to distribute air throughout the data center.
Here are four alternative cooling methods you can implement in a data center to increase efficiency.
Method 1: In-Row Cooling
In-row cooling is one of the newer cooling strategies being deployed in data centers throughout the world. In-row cooling replaces a rack in the row with an air-handling unit. This creates a shorter and more predictable air flow path. In most cases, it eliminates the need for raised floors. Hot air leaving IT equipment is immediately captured by the air-handling units. It’s then cooled and dumped back into the cold aisle. In-row cooling uses the traditional hot-aisle/cold-aisle setup you find in most data centers. Best of all, this method is easy to retrofit into most environments as a replacement or supplement to traditional CRAC units.
Method 2: On-Rack Cooling
Another evolution in cooling technology is on-rack cooling (also known as back-of-rack or rear-door-replacement). This method replaces the back doors of an enclosure with a heat exchanger. This brings the cooling even closer to the heat source than in-row cooling. Hot air leaving IT equipment is never allowed to leave the enclosure before it’s cooled. A unique feature of this cooling method is that it eliminates the need for a hot-aisle/cold-aisle row arrangement in a data center. Because hot air never enters an ambient space, there’s no need to worry about preventing the mixing of hot and cold air. New versions of this technology allow for modular capacity scaling to more closely match the rack density.
Method 3: Heat Wheel
One of the newest technologies adopted in data centers involves a heat wheel. Large rotating wheels bring outdoor air into the environment for distribution under a raised floor in a traditional hot-aisle/cold-aisle arrangement. This same wheel also captures the hot air from the data center, eliminating the heat and expelling the exhaust outdoors. Because it eliminates heat, very little outdoor air is required and little mechanical energy is needed to cool the environment. Since these tend to be among the most energy-efficient cooling products, they are being adopted by more energy-conscious data center operators.
Method 4: Self-Contained Rack Enclosures
As rack densities in closets increase, self-contained rack enclosures are gaining popularity. These rack enclosures have built-in air conditioning that allows IT cabinets to exist in environments not designed as data center space. Recent developments in this technology have allowed for higher capacities, built-in fire suppression, and integration with DCIM and building management systems.
Smarter Cooling Methods
As data centers face increasing demands, greater efficiency is becoming more and more important. By investing in alternative cooling methods, data center operators can reduce inefficiencies without breaking the bank.