Designing data centres for energy efficiency

Stephen Withers
Wednesday, 19 May 2010 11:04

Business IT - Technology

Changes to the way Microsoft builds its data centres are expected to pay dividends in terms of cutting energy consumption.

Microsoft has already achieved a PUE of 1.25 at its Dublin data centre, but the next generation will be even more efficient.

PUE stands for power utilisation efficiency, and is calculated by dividing the amount of power entering a data centre by the amount of delivered to the IT and communications equipment. The lower the PUE, the less power is being 'wasted' on air conditioning, power conditioning, and so on.

One of reasons why data centres needed to be kept within a relatively narrow temperature and humidity range was to accommodate magnetic tape. While large swings in temperature or humidity are still bad for equipment - especially hard drives - most vendors specify a working range of 10 to 35C (50 to 95F), and that allows for more economical air conditioning.

For example, a data centre In the northwest of the US can be kept at 24C (75F) for 99% of the year simply by blending exhaust air on cold days and using evaporative cooling at the air intake on hot days.

Daniel Costello, director, data centre research and engineering at Microsoft, says that 'generation 4' of Microsoft's data centres (which should come online this year) will have a PUE of 1.05 to 1.2.

How does Microsoft plan to approach data centre design? See page 2.