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Critical Facilities and Make-up Water
Critical Facilities and Make-up Water. Data Centers a categorized by tier levels and everything in the data centers infrastructure is checked and classified so that any particular data center can achieve a certain tier level based on the infrastructure in the data center.

Critical Facilities and Make-up Water

Data centers are always classified a critical facilities and need the proper infrastructure to maintain a critical level of performance to minimize any downtime that may occur as a result of a failure in one of the data centers systems or a failure of any utility serving a data center. HVAC Mechanical and electrical systems are redundant in most data center facilities and are scrutinized for dependability and reliability.

A data center can have two chiller plants (one redundant) but what happens if the data center relies only on one source for the make-up water for those chiller plants? Say a local municipality supplies the water used for make-up water. What happens if the main breaks in the middle of the summer when demand for make-up water is high? A redundant chiller plant is no good if the cooling towers do not have water to keep the condenser water cool. Data centers therefore typically have backup sources for make-up water like a well system or even make-up water tanks that will carry the data center a few days until the utility can be restored.

Critical Facilities and Make-up Water - Loss to Evaporation

When making a calculation for how much make-up water will be needed to sustain the data center in the event of a loss of utility an engineer has to assume the make-up water usage on the worst possible scenario or a day when the most make-up water will be used. They must determine how much will evaporate and need to be replaced so the chilled water system can remain functional.

Assuming 1000 kilowatts of cooling load (285 tons of refrigeration) requires 855 gallons per minute of flow they can then determine the average lost to evaporation and make a calculation of how much water the data center will need to sustain itself in the event of loss of water utility. It has been determined that the average loss of water is approximately 1.5% due to evaporation and drift or windage. That means in a 24 hour period a data center using 1000 kW cooling load will require 18,500 gallons of water to sustain itself through a loss of water utility.

To learn more about HVAC and chilled water systems click here.

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Critical Facilities and Make-up Water