Centres de données: technologies de refroidissement et tendances

Dans les dix ans à venir, l'usage d'unités de conditionneurs d'air traditionnels de salles d'ordinateurs est amené à diminuer nettement dans la mesure où les centres de données adoptent des solutions combinant le froid naturel, le refroidissement liquide et le refroidissement par eau glacée.
A newly published market study from BSRIA (IIR partner in economic data) shows that large hyper data centres are changing the market for precision cooling. Over the next five to ten years, the use of traditional computer room air-conditioning (CRAC) units is expected to drop dramatically as data centres opt for a combination of free cooling, liquid cooling and chilled-water cooling.

Hyper scale data centers such as those of Apple, Google, Facebook, Amazon, AWS, Yahoo, etc. are open to deploying “new” technologies, e.g. modular, outdoor AHU’s/evaporative cooling.

Data centre capacity is growing with the increasing number of IP connections, increasing traffic and need for storage. The precision cooling products installed in data centres are estimated at USD 1.9bn covering the 10 largest markets worldwide in 2014. Furthermore, these markets are expected to show healthy growth up to 2017.

The largest market is North America, accounting for around 40% of the global data centre cooling market. China accounts for just under a third and the UK 8%. Other countries include Russia, Germany, France, Australia and Brazil. Germany is by far the largest, accounting alone for 6% of the global market.

The USD 1.9bn does not include precision cooling products installed in non-IT sectors such as healthcare and laboratories, manufacturing, industrial, semi-conductors, education (close control applications in universities and school laboratories). Though smaller than the data centre market, this market is nevertheless substantial.

Case study: data center cooled cost-free 90% of the year in China
In September 2015, a data center was built by Aliyun (cloud division of Chinese Alibaba giant e-commerce) located near the Qiandao Lake in eastern China and using lake water as a cooling agent. The 17°C water is piped up from 35m below the surface, where the temperature is stable and does not fluctuate. Alibaba states that lake water cooling allows the 30,000 m2 data center to cool 50,000 servers cost-free 90% of the year, and is expected to reduce cooling bills by around 80%. The data center also uses renewable energy in the form of solar and hydroelectric power.

Compared to a comparable data center that relies on mechanical cooling, the Aliyun data center is expected to save tens of millions of kilowatt hours of energy annually, according to Alibaba.