Digital Realty Trust has published the industry's first energy efficiency data about its datacentre facilities. Digital Realty Trust will use the Power Usage Effectiveness (PUE) metric as the methodology for measuring and reporting energy efficiency in its portfolio of facilities in North America and Europe.

PUE is an emerging standard promoted by The Green Grid and others in the datacenter industry to provide a simple and consistent method of measuring the ratio of power delivered to IT equipment to the total amount of power used by the datacentre facility. PUE provides reliable information about the energy efficiency of datacenter facilities by calculating how much power is devoted to driving the actual computing/IT components (servers, for example) versus the ancillary support elements such as cooling and lighting.

"Significant gains in energy efficiency can be achieved by designing, building and operating datacenters in ways that reduce the overall power needs of the datacenter. This translates into minimizing the amount of power required by non-IT equipment and maximizing the ratio of power used by computing systems like servers," said Jim Smith, Vice President of Engineering at Digital Realty Trust. "Digital Realty Trust has been a leading voice on this issue since well before it gained the prominence it has today, and has achieved a number of important industry milestones related to green datacenters. However, I believe that reporting the PUE metric for our datacenter facilities is the most significant milestone yet because it will provide a model and benchmarks that can be used industry-wide to achieve dramatic increases in energy efficiency and can be used by customers to compare the energy efficiency of different datacenter facilities."