Running Servers around Zero Degrees

Data centers are a major consumer of electricity and a significant fraction of their energy use is devoted to cooling the data center. Recent prototype deployments have investigated the possibility of using outside air for cooling and have shown large potential savings in energy consumption. In this paper, we push this idea to the extreme, by running servers outside in Finnish winter. Our results show that commercial, off-the-shelf computer equipment can tolerate extreme conditions such as outside air temperatures below -20 C and still function correctly over extended periods of time. Our experiment improves upon the other recent results by confirming their findings and extending them to cover a wider range of intake air temperatures and humidity. This paper presents our experimentation methodology and setup, and our main findings and observations.