Cooling has become a hot topic for data centers, and it will remain a major interest in the immediate future. According to a report from Global Market Insights (GMI), the data center cooling market is exploding, driven by the growth of data centers and the amount of information they store. From government centers to large enterprises, today’s tech-driven world demands an environment that can protect systems and processors from damage due to heat and humidity, while at the same time being cost effective and environmentally friendly.
In 2016, GMI reports, about $8 billion was spent worldwide on data center cooling. By 2024, that number is expected to reach $20 billion. With equipment power consumption accounting for about 40% of a data center’s energy usage, the need for cost-effective and energy-efficient solutions has never been more important. Optimum cooling is essential to prolonging the life of hardware and increasing performance, but the solution must also be financially viable for data center operators.
As cooling options become more important, some traditional methods such as the use of hot and cold aisles are being joined by newer cooling approaches. One is liquid or water cooling, which is quickly becoming a contender to replace costly mechanical air-based cooling.
Water Cooling Makes a Splash
Data centers have been reluctant to use water cooling for one primary reason: fear of spillage. When the need first arose for data center cooling, enterprises already had air-conditioning systems in place, so using air to handle the additional cooling needs of the computer room was a logical choice. But as rack power densities have increased, air cooling faces more challenges and, subsequently, becomes more expensive.
At the same time, the advantages of liquid cooling—which is already widely used in personal computers and servers—are becoming more apparent for data centers. As a result, companies such as cooling system manufacturer Asetek are betting the future on data centers.
In October, the Oslo-based company announced it had set its sights on the data center cooling market. Although 91% of its revenue is still tied to the desktop market, CEO Andre Ericksen told Bloomberg that he believed the company’s future was in data center cooling—specifically, liquid cooling.
Asetek is far from alone in that belief; Canada’s CoolIT Systems and California-based Chilldyne are also among the liquid-cooling players that are targeting the data center market.
Making the Case for Replacing Air
Traditional data center cooling strategies have been notoriously costly and inefficient. With raised floors as well as computer-room air-conditioning (CRAC) units and computer-room air handlers (CRAH), data centers have required a great deal of energy to chill. They must often be able to reduce the room temperature to less than the ambient temperature outside, which can become more challenging in warmer climates or during particularly hot times of the year.
Adding to the challenge is that the cooled air must travel a considerable distance from the cooling unit to the equipment that needs cooling. This requirement only adds to the expense and inefficiency of the system. Moreover, the air needs help displacing the heat, so rack and blade fans are necessary as well.
Pushing the cooled air through servers using server fans also requires a significant amount of effort and energy, and as rack densities increase and interconnect distances increase, air cooling faces even greater challenges in the modern data center. Although air can cool the data center space, liquid is better at absorbing the heat, which makes it more efficient.
Counting the Cost of Liquid Cooling
Today’s liquid-cooling equipment has eliminated the universal concern of water leaks, although not all leaders are completely convinced of its safety. Still, in recent years, hardware manufacturers have demonstrated that they’ve minimized risk while at the same time optimizing performance.
When comparing cost, it’s often an apples-to-oranges analysis because the two cooling approaches have different needs. For example, liquid cooling uses either water or a manufactured liquid, but the water must be filtered for contaminants. Certain maintenance costs, such as ongoing water treatment, must be factored into operation of liquid systems, but the energy costs are less and the liquid is more efficient and cools the air faster than air.
Since water and air have different densities, a line-by-line comparison is almost impossible. But more data centers are eyeing the advantages of liquid cooling as a way to reduce waste, costs and their carbon footprint. As both businesses and consumers increase data centers’ demand for energy, the concern about cooling costs will continue factoring into their decision about which methods can best serve them. Rising energy prices and government regulations will be also be of concern regarding how to best store and process data safely. On a global level, green strategies are becoming top of mind. The ability of liquid-based solutions to provide advanced, efficient cooling (while reducing carbon footprint) will continue to make them a better option than air cooling.
About the Author
Tiffany Bloomer is president of Aventis Systems, an informational technology company in Atlanta, Georgia. Tiffany has been proud to work in the IT field for over 10 years.