20 April 2010
ASHRAE standard is too prescriptive says Google
GOOGLE and other data centre owners have objected to a proposed ASHRAE efficiency standard.
ASHRAE Standard 90.1 defines the energy efficiency for most types of buildings and has recently been extended to include data centres.
The data companies, which include Google, Microsoft, Nokia and Amazon, object to proposed amendments in the standard requiring air or water economisers as part of the standard data centre design
In an open letter posted on the internet by Urs Hoelzle, senior vice president, operations and Google fellow and five co-signees, the group maintains that efficiency standards should be performance-based and accuses the ASHRAE standard of being 'too prescriptive'.
'Instead of setting a required level of efficiency for the cooling system as a whole, the standard dictates which types of cooling methods must be used,' the letters says.
'For example, the standard requires data centres to use economizers -- systems that use ambient air for cooling. In many cases, economizers are a great way to cool a data centre, but simply requiring their use doesn't guarantee an efficient system, and they may not be the best choice. Future cooling methods may achieve the same or better results without the use of economizers altogether. An efficiency standard should not prohibit such innovation.'
In response, ASHRAE has maintained that there are eight exceptions to the mandatory usage of economizers. 'The addendum does not change the portion of the standard that already allows, through the Energy Cost Budget method, for data centres to be designed without economizers if other energy saving methodologies, including power usage effectiveness is employed,' it added.
The stance of the data centre owners was supported by UK cooling equipment manufacturer Airedale. Director of engineering Bill Coates said 'I agree with this stance as many applications are location specific and would support open innovation solutions always.'