For over 15 years The Green Grid’s Power Usage Effectiveness (PUE) metric has been the go-to method of benchmarking a data centre’s energy efficiency and identifying ways to improve it. Getting as close to the figure of 1.0 has become something of an industry obsession, which has led to some data centre operators making spurious claims about low PUE ratings by ‘reinterpreting’ the way that it is calculated.

Sadly, despite the good intentions behind it, in many respects the PUE metric has been so misunderstood, misapplied and abused that its credibility has been severely dented. Furthermore, it only measures the energy used for the IT rather than the entire facility and doesn’t consider how the electricity is sourced, the heat generated or the amount of water used for cooling.

Nvidia has now thrown its views into the mix, stating that in the era of artificial intelligence (AI), the calculations offered by the PUE metric are no longer sufficient and that a new way of measuring and improving energy efficiency is needed. So, is it time to move on? In this issue’s Question Time we’ve asked a specially selected panel of industry representatives to answer that and suggest the best way for data centre operators to accurately assess their energy performance and efficiency.

Edge data centres continue to offer numerous benefits including reduced latency by processing data closer to the source, which improves performance for real-time applications. We take an in-depth look at the latest developments in this area and Chad McCarthy of nLighten examines how edge data centres are fuelling the energy transition and bringing carbon free heat closer to customers. Chad is joined by Chris Coward of BCS, who discusses how edge solutions promise to benefit a wide range of sectors, while Mark Lewis of Pulsant explains how adopting an edge architecture can help to implement the lessons of the CrowdStrike outage.

We also have a special feature dedicated to sustainable network infrastructures with two excellent articles. First up, our old friend Brian Duval looks back at nearly two decades of being involved in Siemon’s environmental efforts and offers his view of how long-term sustainability goals can truly be achieved. Dean Boyle of EkkoSense then goes on to explain why establishing clear accountability around data centre sustainability reporting is so important.

Rob Shepherd
Editor