Since its inception, a widespread criticism of Power Usage Effectiveness (PUE), The Green Grid metric that measures the efficiency by looking at the power delivered to the facility and then what of that that is passed on to compute equipment, has been that it doesn’t take into account geographical challenges with power. Critics have said this doesn’t allow a level global playing field when it comes to comparing data centers. As a result, governments have started looking at how they can develop national ratings that more fairly reflect energy efficiency and wider environmental concerns and conditions that apply to specific geographies.

Australia is one of those nations. Not shy about its goals for a more green economy, it is introducing the Carbon Reduction Tax this year, which will have a large effect on data center operators. In February, it also introduced NABERS (The National Australian Built Environment Rating System) for the data center.

We first reported on the development of NABERS (NABERS has been in wide use by those leasing and managing office space in Australia for some time now) back in June 2011. At the time, the New South Wales Office of Environment and Heritage environment manager Yma ten Hoedt, who was working on the development of the standard with the national government, said the aim was to identify what it was that made Australia’s data centers unique. Findings would be coupled with metrics like PUE, lessons used and learned from providers such as participating operators like Equinix and Fujitsu and initiatives being undertaken elsewhere around the world.

“NABERS tools traditionally measure the performance of a tenancy, a base building, or a whole building,” ten Hoedt said. “The NABERS Energy for Data Centers tool will work in a similar way, covering an IT Workload rating for tenancy data centers, Infrastructure rating for colocation data centers and a Whole Data Center rating which combines both.”

What NABERS is
The outcome is a six-star rating where a rating of 1 represents below-median market practice. “NABERS Energy for data centers converts the energy consumed by the data center to full fuel cycle greenhouse gas emissions (including the emissions from energy that is lost through transmission and distribution losses) and uses them to benchmark its energy performance,” NABERS says.

The government says operators can improve their rating by reducing energy consumption or by purchasing low or zero emission energy sources.

The rating uses three tools for assessment: An IT Equipment rating which benchmarks greenhouse gas emissions associated with energy consumed by the IT equipment in a data center over a one-month period; an Infrastructure rating for emissions associated with the supply of IT infrastructure services to IT equipment in a data center over 12 months; and a Whole Facility rating tool, which covers both.

NABERS says its IT equipment Rating tool is a world-first. “Experience in developing the NABERS Energy for Data Centers rating tools has shown that Australian data centers have limited energy monitoring and sustainability reporting. As a result, NABERS focussed on developing simple, measurable benchmarks based on the most readily accessible data,” NABERS says.

The rating focusses only on processing, storage and networking, and covers processing capacity – measuring the sum of the number of server cores multiplied by clock speed in gigahertz, and storage capacity, measuring the total unformatted storage capacity in terabytes.

It then predicts an industry median for greenhouse gas emissions for an amount of processing and storage capacity and rates the facility based on this.

The IT Infrastructure rating is quite straight forward – it is based on PUE. It focusses on the electricity consumption of IT equipment and infrastructure services energy consumption using readings form utility meters or validated non-utility meters.

For the Whole Facility rating, both IT equipment and infrastructure services have to be deemed energy efficient to provide a favourable outcome.

This article first appeared in FOCUS 28. You can sign up to our digital editions, and read the full publication, here. You can also have your say on the content in FOCUS, by taking part in our short survey here.