On the second day of the 7x24 Exchange fall conference, here in San Antonio, John Pflueger, Tahir Cader, and David Sterlace sat down to talk about sustainability and efficiency in the data center.
The conversation centered on the continued need for energy management in the data center and the huge strides that have been made in the last few years, not least of which are the Green Grid’s many metrics for measuring and therefore, hopefully, managing energy consumption going forward. These include the well-known Power Usage Effectiveness (PUE) metric, Water Usage Effectiveness (WUE), Carbon Usage Effectiveness (CUE), and the Energy Reuse Effectiveness (ERE) metrics. We all know the value and importance of PUE in managing energy usage in a data center. It’s mentioned in every new build and drives nearly every major data center purchasing decision. But sustainability in the data center is not just about power. Less often discussed is WUE and its importance in light of today’s droughts around the country, especially in California. When considering technologies like evaporative cooling, a careful balance must be found between better energy efficiency and the effective use of water. While evaporative cooling does significantly help to reduce electricity consumption, and therefore improve PUE, it also uses considerably more water than a traditional chilled water system. All these factors have to be balanced and the resources weighed.
Cader also talked about liquid cooling, which is still a pretty radical idea in most data center circles. However, in the high performance computing arena, according to Cader, this is quite commonplace. National labs, in particular, are managing compute intensive workloads – like human genome mapping or weather modeling – that generate an immense amount of heat and require a new approach to cooling. He believes that the liquid cooling that is currently adopted at large and innovative data centers will trickle down to enterprise data centers in the next decade as more case studies are available to prove its viability as a safe and effective means to limit electricity costs.
Like the liquid cooling, power purchase agreements (PPA) for renewable power are another tactic used by very large data centers to reduce their carbon footprint currently, but is something that John Pflueger believes will be adopted by the mainstream data center eventually. Right now, the economics of a power purchase agreement only work out for data centers that use a huge amount of power. However, the cost for those PPAs is coming down and will eventually become more feasible for the rest of the market. In the future, we may also see companies pooling their power needs to enter into PPAs together.
DCIM and monitoring also play a role in all of this - these tools cannot just be for passively collecting metrics but need to be actively used to make a difference in power usage. ABB’s David Sterlace is currently seeing more adoption of DCIM software from the commercial side of the data center space than from brand-name customers. It seems that customers of data centers want to know more about where their servers are collocated or hosted and ensure that all the systems are working together efficiently to deliver the lowest PUE values.
While power use is still an important component of the sustainability picture, Pflueger, Cader, and Sterlace stressed that it’s about a lot more. Sustainability efforts need to incorporate water, carbon emissions, and labor efficiency as well. We look forward to hearing more from these three as their efforts to improve sustainability in data centers continue.