Page 241 - Shaping smarter and more sustainable cities - Striving for sustainable development goals

Figure 12 – Rack mounted servers

2.1.1.7 Environmental control

The physical environment of a data center must be rigorously controlled. Air conditioning is used to
control the temperature and humidity in the data center. Some guidelines recommend a
temperature range of 18–27 °C (64–81 °F), a few point range of 5–15 °C (41–59 °F), and a maximum
relative humidity of 60% for data centers environments. The temperature in a data center will
naturally rise because the electrical power used heats the air. Unless the heat is removed, the
ambient temperature will rise, resulting in malfunctioning of the electronic equipment. By
controlling the air temperature, the server components at the board level are kept within the
manufacturer's specified temperature/humidity range. Air conditioning systems help control
humidity by cooling the return space air below the dew point. Too much humidity and water may
begin to condense on internal components. In case of a dry atmosphere, ancillary humidification
systems may add water vapour if the humidity is too low, which can result in static electricity
discharge problems which may damage components. Subterranean data centers may keep
computer equipment cool while expending less energy than conventional designs.

Figure 13 – Air conditioning equipment

ITU‐T's Technical Reports and Specifications 231