Understanding Data Center Power Usage Effectiveness

DAMAC FasTrak

PUE is a measure of how much energy is actually used by computing equipment versus cooling and other overhead.

The concept of power usage effectiveness (PUE) has been in the news lately since a Welsh data center claimed to achieve a perfect score of 1.0. The claim is something of a marketing gimmick, which has many data center wonks crying foul. But the story begs the question of what is PUE and how does one go about achieving that perfect 1.0.

PUE is a measure of how much energy is actually used by computing equipment versus cooling and other overhead. It is calculated by dividing the total energy a data center consumes by the amount used by the computing equipment. If the two numbers are equivalent — meaning that all energy goes to computing equipment — then the ratio will be 1.0.

Is that even possible?

The Next Generation Data (NGD) facility in Walesicenc says that it has achieved a “contractual” PUE of 1.0 by using solar power. The facility has installed 4,000 photovoltaic solar panels on its large, flat roof, and NGD estimates that over the course of a year those panels will produce enough energy to offset any power consumed by non-IT equipment. Because solar power is sustainable and comes at no cost to the data center’s customers, NGD feels justified in claiming a PUE of 1.0.

There’s no question that the NGD facility is highly efficient — calculated in the conventional way, its PUE is 1.18. That’s close to the energy efficiency of industry leaders such as Google and Facebook, whose facilities have PUEs approaching 1.0.

DAMAC Rack Airflow

DAMAC Racks feature patented designs that allow for maximum airflow to cool equipment.

The typical data center, by contrast, is highly inefficient. A February 2014 survey by Digital Reality found that the average data center has a PUE of 2.9, with 20 percent reporting a PUE below 2.0 and 9 percent reporting a PUE of 4.0 or more. Digital Reality believes its statistic represents the PUE of the typical data center, and that the Uptime Institute’s 2013 estimate of 1.8 to 1.89 is unrealistic.

Older, inefficient equipment and underutilized resources can contribute to a high PUE, but data center design is a key factor. That’s why four out of five respondents to the Digital Reality survey said they are taking steps to prevent hot exhaust air from mixing with cold air in the data center environment, and 85 percent are using some type of data center infrastructure management (DCIM) software.

DAMAC can help organizations reduce their PUE ratio. Our racks and cabinets feature patented designs that allow for maximum airflow to cool equipment. Our aisle-containment systems can quadruple cooling efficiency by isolating hot and cold air. That’s why you’ll find DAMAC products inside some of the world’s most advanced facilities.

While we can’t promise you a PUE 1.0, we can help you increase your energy efficiency.

Contact us to learn how you can put the design practices of industry leaders to work in your environment.