IT equipment has to breathe too! Data center technology uses electricity to operate and produces heat as a result. Think of heat as a waste product like exhaust from your car or sweat when you work out. Since data centers are typically in enclosed rooms, this heat has nowhere to go. If heat does not have a good escape route, then it will quickly make the entire data center hot. In turn, this will damage server equipment and cause downtime.
Because of this, data centers need cooling. However, it is important to note that your data center does not have to be as cool as your house. The allowable temperature for a data center is as high as 104 degrees Fahrenheit as stated by the American Society of Heating and Air-Conditioning Engineers (ASHRAE). So even though data centers do need to be cooled, they do not have to be cooled to personal comfort temperatures.
Options for Removing Heat
The process for cooling equipment is relatively simple: move the heat from the inside to the outside of the server environment. Doing this allows equipment to operate better and live a longer life.
There are two different cooling methods that are typically used: air cooling or liquid cooling.
Air cooling is a more natural approach since air is already in the data center. Air also moves easily and is not damaging to valuable IT equipment. Traditionally, computer room air conditioners convert warm air to cool air by removing heat to the outside. Air cooling solutions primarily rely on the separation of warm air and cold air since warm air rises to give way to cold air. However, there may be issues in the data center if warm air and cold air mix. Some data centers will go so far as to create hot aisles and cold aisles. Air inlets face the cold aisle and exhaust outlets face the hot aisle. This minimizes the chance of cold air and hot air mixing, and it is more efficient.
Liquid cooling can be a more efficient and effective solution since it is more targeted. Chilled water can be delivered to the exact location that needs cooling rather than attempt to cool the entire data center. However, this solution comes with a few risks. Water leaks threaten to damage valuable equipment and more infrastructures are required to contain the water. Additionally liquid cooling solutions are more expensive than air cooling solutions. However, liquid cooling solutions are better for high density applications. Similar to air based cooling, liquid based cooling removes heat to the outside. However, liquid cooling employs chillers often with the assistance of a cooling tower, to provide cool water or refrigerant. This chilled liquid is then transported either to the entire data center or just to certain server racks that are in need of cooling.
Cooling your data center for free sounds like a great deal. Unfortunately, free cooling is not actually free. This term simply refers to using either air cooling or liquid cooling as mentioned above in a more efficient manner. Often called air-side or water-size economization, free cooling minimized the use of your cooling infrastructure. Air-side economization involves using outside air to cool the data center. Think of it as opening the windows on a breezy day. The risk of outdoor contaminants entering the data center and damaging valuable equipment is a factor in this solution. However, there are many solutions that filter the air for outdoor contaminants. Similarly, water-side economization uses outside air and evaporation techniques to cool liquid without chillers. Since ASHRAE has increased the allowable temperature for data centers, the free cooling method has been used more and more. This method allows organizations to save energy and money by using this more cost efficient cooling method.
Just as a general rule of thumb for cooling, make sure to face all equipment in the same direction so that the intake of one device is not inhaling the exhaust heat of another device. Overall, data center cooling methods are going to vary based on the conditions and circumstances of the data center location. It is important to select the solution that is going to meet the heat removal needs of your data center whether that is air cooling or liquid cooling. Removing heat from the data center is imperative to the life of your valuable equipment. You can prevent outages, downtime, and equipment failure with proper cooling techniques. And with free cooling, you can find the most cost effective and energy efficient ways to cool down your equipment.