That’s always been the case. It’s a higher urgency topic, however, due to the explosion of data center demand.
In June, the the Department of Energy’s Lawrence Berkeley National Laboratory released estimates that said that in 2014 — the latest year for which figures have been analyzed — data centers used 70 billion kWh, which was about 1.8 percent of total consumption of electricity in the United States. The lab estimates increases of 4 percent each from 2010 to 2014 and from 2014 to 2020.
This is being driven to a great extent by spending in the increasingly sophisticated public cloud sector. At the beginning of this year, IDC reported that worldwide spending on such services — all of which leverage data centers — would experience a compound annual growth rate (CAGR) of 19.4 percent from last year to 2019. That will double spending from $70 billion to $141 billion over the term of the research.
The silver lining obscured by the gaudy numbers is that the rate of energy use increases is slowing dramatically. Data center energy is estimated to have increased by 90 percent from 2000 to 2005 and by 24 percent from 2005 to 2010. To get down to 4 percent increases — especially when they are juxtaposed against significant increases in demand — is a significant achievement.
The slowing of the increase in data center energy use no doubt is due to increases in efficiency both of server and switch gear and the equipment and approaches used to cool it.
One of the most intriguing emerging approaches to data center cooling is liquid immersion. As the name implies, this is the use of a flow of water, dielectric fluid, mineral oil or refrigerant to cool equipment, according to Saahil Tumber, senior associate and lead mechanical engineer at Environmental System Design. In addition to the choice of different types of coolant, his story at Consulting-Specifying Engineer points out that there are a choice of ways in which these systems can be engineered.
There are many issues of which to be aware when choosing this option. Great care is justified: Cooling is just about the most important element in a data center. If it fails, the results almost certainly will be dire. One example of how a simple mechanical decision — one that may not even reach the level of top engineering and planning executives — can make a big difference:
Similarly, the use of inert pipe materials, such as stainless steel and copper, and use of mechanical joints in lieu of welding, soldering, or brazing should be discussed with the technology provider. Any contamination of liquid due to incompatibility with materials of construction can have serious repercussions and can lead to catastrophic failure of the ITE.
The benefits clearly outweigh the challenges and liquid immersion data center cool is growing. Last week, Technavio released research that said that the global market for the technology will grow by a CAGR of 54 percent from this year through 2020.
Clearly, the high growth rate is to some extent due to the immaturity of the market sector. Despite that caveat, however, it still is significant growth. Technavio says that liquid immersion systems consume as much as 90 percent less energy than air-based computer room air conditioner (CRAC) systems. The top vendors, the reseach says, are Allied Control, Asetek, CoolIT, Green Revolution Cooling, Iceotope, LiquidCool Solutions and Midas Green Technologies.
High Performance Computing, in an article that mentions Chinese firm Sugon’s liquid immersion cooling technology, makes a very important point. As cooling efficiency increases, devices can be placed more closely together. This can be create a second benefit: Not only does the technology hold out the possibility of decreasing cost for cooling, but it also can mitigate real estate costs by squeezing a given amount of data center capacity into a smaller space. This also reduces non-cooling overhead costs.