Google built a data center in Hamina, Finland, using Baltic Sea water to cool systems instead of chillers. Last October, Facebook announced that it had begun construction of a data center in Lulea, Sweden , near the Arctic Circle, to take advantage of the cool air. Hewlett-Packard built a facility that relies on cold sea air just off the North Sea coast in the U.K.
One project that is carbon free is a data center built by Verne Global in Keflavik, Iceland. The power supply comes from a combination of hydro and geothermal sources.
The cool temperatures in Keflavik allow the data center to make use of outside air for cooling. The company has two modes of operation; one is direct free cooling, which means air is taken directly from the outside and put into the data center. The company can "remix" the returning hot air to have "tight temperature controls," said Tate Cantrell, the chief technology officer. The air is also filtered.
The data center also has the ability to switch to a recirculation mode where no outside air goes into the data center. Instead, a heat exchanger with a cold coil and a hot coil is used. The cold coil cools the air in the data center air stream, and the hot coil is cooled by the direct outside air, Cantrell said.
The Keflavik data center will use the heat exchanger in two situations. The first is to conserve moisture in the air when the dew point is low, meaning there is a low percentage of water in the airstream. The data center also has humidifiers. Below a certain level of humidity there is a possibility of introducing static into an environment. The other reason for switching to a heat exchanger is to protect the filters in the event that a strong storm kicks up a lot of dust, said Cantrell.
The groundbreaking of the Berkeley facility last week included Steve Chu, the U.S. energy secretary and a former Berkeley Lab director. He said the computational facility, "is very representative of what we have that's best in the United States in research, in innovation." Computation will be "a key element in helping further the innovation and the industrial competitiveness of the United States," he said.
Read more about data center in Computerworld's Data Center Topic Center.