Google Leads Criticism Of Green Data Centre Rules

A bid to impose efficiency standards on data centres has been met with resistance from a group of industry leaders, led by Google, who claim to represent most of the world’s most advanced data centre operators.

Google, Microsoft and Nokia have all signed a blog post, which complains that a bid to extend a building efficiency standard to data centres will cause problems because it is “too prescriptive”.  The ASHRAE 90.1 standard from building efficiency, from the American Society of Heating, Refrigerating and Air-Conditioning Engineers,  is to be applied to data centres – but the operators believe it will push specific technologies, instead of rewarding better results.

Free-air cooling could be mandatory?

The ASHRAE standard – which could be applied by local building regulation enforcers – recommends the use of free-air cooling, delivered by so-called “economisers”. While Google and its allies believe free-air cooling is a good thing and use it widely, they do not want to have it set in stone, as this might prevent future improvements in efficiency measures.

“We believe that for data centres, where the energy used to perform a function (e.g., cooling) is easily measured, efficiency standards should be performance-based, not prescriptive,” says the blog post. “In other words, the standard should set the required efficiency without prescribing the specific technologies to accomplish that goal.”

Results-based measurements include Power Usage Effectiveness (PUE) – a simple measure promoted by the Green Grid, which was adopted by several international bodies including the European Union earlier this month. This is a simple ratio, comparing the power delivered to the servers, with the total power used by the data centre.

ASHRAE has defended its standard in an email sent to the Data Center Knowledge site, which points out that the standard actually includes an option to use schemes like PUE. “The addendum includes eight exceptions to requirements for the use of economizers in data centers,” said the email. “The addendum does not change the portion of the standard that already allows, through the Energy Cost Budget method (an alternate method of compliance), for data centers to be designed without economizers if other energy saving methodologies, including power usage effectiveness (PUE), are employed.”

The Google-led group has not withdrawn its objection, however, The group believes that including a specific technology, even if an opt-out is allowed, is likely to cause trouble. “A key concern is how the standard will be interpreted by local building officials, who may not always be well versed in alternate compliance methods,” explains Data Center Knowledge.

The PUE measure has gained global acceptance, with data centre operators publishing impressive results, driving down from today’s not-very-good levels of 2.0, towards an ideal level nearer 1.0. Most seem willing to use the standard, although it has been criticised for ignoring the full lifecycle of a data centre, and the Green Grid has warned that it should not be used to compare data centres.