Glossary
acre-foot
A unit of volume used to measure water; the amount of water needed to cover one acre of land (43560 square feet) to a depth of one foot. One acre-foot is equivalent to about 1,233 m³.
air cooling
A data center cooling method that uses exclusively air conditioning systems to circulate cool air over hardware to dissipate heat.
chiller
A machine that removes heat from a liquid coolant through vapor-compression, adsorption refrigeration, or absorption refrigeration cycles.
colocation center
Sometimes shortened to colo, a type of data center that rents out equipment, space, and bandwidth to retail customers, as opposed to single-tenant hyperscale data centers.
cooling tower
A device that rejects heat to the atmosphere by cooling a coolant stream (usually water) to a lower temperature, using either evaporation or air to cool the fluid.
CRAH
Computer Room Air Handler; an HVAC unit that provides precise cooling and humidity control for data centers and server rooms by circulating cold air, often through connection to an external chilling system.
evaporative cooling
A data center cooling method that passes hot air over a water-saturated pad or through a heat exchanger, causing water to evaporate and drawing heat from the air to cool the data center.
facility power
The total amount of electricity required by a given data center to run all of its equipment, including IT infrastructure and support systems like cooling and lighting; used to calculate PUE.power usage effectiveness.
free cooling
A data center cooling method used in cool climates that circulates naturally cool air or water to reduce reliance on mechanical refrigeration.
hyperscale data center
An extremely large facility that houses vast numbers of servers and storage systems, designed for extreme scalability and efficiency to meet the data demands of "hyperscale" businesses like large cloud service providers and social media companies.