cooling
FINDING THE CURE
‘ Treat the cause , not the symptom ’ is a phrase often used by alternative medicine practitioners . The saying is particularly relevant when applied to cutting the cost of cooling data centres , explains Bob Cantrell , senior application engineer at Ericsson Power Modules .
Cooling the computers that drive our data centres costs money . Operators are keen to minimise the utility costs associated with running the cooling fans and air conditioning systems that do the lion ’ s share of the work . In hot weather , the extra loading on these systems can add as much as 50 per cent to a data centre ’ s electricity bill .
A number of responses have been tried , seeking to minimise the energy consumed by cooling systems , which , it can be argued , simply adds to operating costs without directly increasing value for customers . These solutions can be put broadly into two categories : those that attempt to move the goalposts and those that treat the symptom .
Move the goalposts The capital and operating costs of cooling systems can be reduced by accepting higher equipment operating temperatures . There has been a great deal of research into establishing and reevaluating acceptable operating temperatures to ensure acceptable reliability . ‘ Cooler is better ’ is a well known mantra throughout the electronics industry , and this has applied in data centres as well .
When the cost of data centre cooling is taken into account , ‘ cooler is better ’ becomes less tenable : an acceptable limit is more desirable . A typically accepted ambient temperature range for data centres has been in the region of 68-72 ° F . Some have operated at significantly lower temperatures , in the region of 55 ° F , and water chillers are often used in data centres to help keep the temperatures down . These are expensive to run .
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