IBM's in Hot Water to Cool Servers
IBM researchers and the Swiss Federal Institute of Technology Zurich (ETH Zurich) have launched Aquasar, a supercomputer with a new cooling system that isn't all that cool. Rather than chill the system down to refrigerator temperatures, IBM lets things get hot. Very hot. The latest idea in supercomputer cooling is to let the machines operate at something warmer than meat locker temperatures.
Aquasar is a supercomputer that uses water to cool its blade servers' processors, in lieu of using a heat sink and fan. But instead of chilling the water down to the 50-60 degree Fahrenheit mark, Aquasar uses water that's up to 140 degrees Fahrenheit (60 Celsius). That's because the safe operating temperature for IBM's processors is up to 185 degrees (85C), so in this case, "cooling" becomes relative.
By eliminating the cost of chilling the water, customers can save up to 40 percent of their energy costs over air-cooled systems that use air conditioning and a lot of fans. The boiling hot water is carried away from the servers and used to heat homes around the ETH Zurich facilities. By the time it circulates back to the computer center, it has cooled down.
It's not the first time cooling has defied the conventional wisdom of making the system as cold as possible. In 2008, Intel conducted experiments in a New Mexico data center in the desert and found ambient temperatures were safe for data center systems. It may not be comfortable for the people working around the machines, but the machines can certainly take it.
The overall Aquasar compute cluster is a combination of IBM BladeCenter blade systems using the hot water cooling system as well as some that use air cooling. All told, Aquasar has three BladeCenter H chassis with a total of 33 BladeCenter QS22 servers that use IBM's PowerXCell 8i processors, a derivative of the Cell Broadband Engine used in the Sony PlayStation 3. It also includes nine BladeCenter HS22 systems that contain a pair of Intel Xeon 5500-series processors chips.
IBM estimates that the heated water coming out of the computer sends about 9 kilowatts of thermal power into the university building's heating system, thus cutting down not only on all the power needed to cool the Aquasar, but also the power needed to heat the facility.
"With Aquasar, we achieved an important milestone on the way to CO2-neutral data centers," Bruno Michel, manager of Advanced Thermal Packaging at IBM Research-Zurich, said in a statement. "The next step in our research is to focus on the performance and characteristics of the cooling system, which will be measured with an extensive system of sensors, in order to optimize it further."
The idea of turning up the temperature in data centers is slowly gaining ground, but caution remains on the part of data center administrators, said Jed Scaramella, senior research analyst for IDC's Enterprise Platforms and Datacenter Trends.
The idea of turning up the temperature in data centers is slowly gaining ground, but there is caution on the part of data center administrators, said Jed Scaramella, senior research analyst for IDC's Enterprise Platforms and Datacenter Trends. While some industry groups like The Uptime Institute have been saying it's OK to let your server room temperatures rise, data center managers are taking it slow "because data center managers are risk-averse. Their first priority is to keep the systems up and running," he told InternetNews.com.
He added that companies that build data center cooling and air conditioning gear like Emerson, American Power Conversion and Liebert are starting to get the message to server vendors like IBM that system internals, such as the CPU temperature, are more important than the room temperature in the data center room. "If you walk into the room and the room is cold, that doesn't tell you much," Scaramella added.