The Pros and Cons of Data Center’s Liquid Cooling  

We are living in the era of big data, especially with the development of AI technology, the amount of data is increasing by geometric multiples. Data centers that undertake these data operations and storage also have a trend of high-density and high-power. One problem brought about by such development is heat dissipation. The traditional air-cooling and cooling system has gradually become overwhelmed, and liquid-cooling technology has emerged due to its higher efficiency and lower energy consumption.

The so-called liquid cooling is not simply water. It refers to the high specific heat capacity of the liquid as a transmission medium, taking away the heat generated by the IT equipment or the server. In fact, as early as the 1960s, IBM began to use the predecessor of liquid cooling technology, that is, water cooling technology. Today's liquid cooling technology is mainly used in the field of high performance computing due to cost issues.

What are the coolants for liquid cooling technology?

Water

The most direct and the least expensive coolant is water. However, since water is not an insulator, it can only be used for indirect contact liquid cooling. In addition, security protection is very important. It will do great damage to IT equipment if a leak occurs.

mineral oil

In addition to water, mineral oil is also an inexpensive coolant. Single-phase mineral oil is non-toxic, odorless and non-volatile. However, due to the high viscosity, it is easy to form a residue on the surface of the device.

Fluoride

The biggest characteristics of fluoride are insulation and incombustibility. It is the safest type of data center liquid cooling technology and is currently the most widely used. But its high price has made many manufacturers who are interested in liquid cooling technology disappointed.

Thanks to higher heat dissipation efficiency, lower dependence on buildings, quiet and safety, those data centers with higher site and power requirements will gradually consider liquid cooling technology. In addition to the traditional large-scale data center, with the advent of the edge computing era, about 20% of the future edge computing data centers will use liquid cooling technology.

Constraints

1. Lack of corresponding standard support

At present, immersed liquid cooling has not formed a trend in the industry, and there is no case of large-scale application. And some countries or industry's specifications for its technology are also vacant.

2. The cost of reconstruction is too high

Data centers using liquid-cooled technology are designed differently from traditional air-cooled data centers. Such as the weight of the stairs, the height of the machine room and so on. If the cooling method is changed rashly, in addition to the impact on space utilization, personnel maintenance and re-construction costs will also cost a lot.

3. Corrosion risk

As mentioned above, water is electrically conductive, while mineral oil and fluoride will be contaminated by other substances after contacting with air, posing a risk of corrosion to IT equipment such as servers. The cost of prevention for this is high.

However, although there are still many problems in liquid cooling technology, thanks to its obvious advantages, it will certainly be useful in the future construction of data centers.