The past few years have seen the increasing perception that the “cloud” is a far more sustainable approach to computing than on-premises IT infrastructure. Now, like most things—i.e., a switch to electronic media, etc.—the race toward the clouds is not being predominantly driven by “green” concerns, but rather by issues of cost and convenience. That there are elements of cloud computing that are more sustainable than terrestrial computing (a term I just made up to refer to the alternative, since “single-tenant architecture” sounds like a studio apartment) is a happy accident. For the uninitiated, the “cloud” refers, basically, to storage, applications, files, etc., all stored in a centralized location online rather than on individual workstations. Sometimes the term “software as a service” crops up.  The advantages of using the cloud include cost savings on dedicated in-house (or “on premises”) IT infrastructure, as well as the ability to access data and files from any device, an important concern as more and more people use mobile devices of one sort or another, and copying files back and forth from a tablet to a proper computer to a smartphone is needlessly repetitive and time-consuming. There’s no doubt that the cloud saves time, money, and resources, but attempts at quantifying the environmental benefits of cloud computing have been a bit blunt instrument-like. But a new white paper commissioned by Salesforce.com—one of the “pioneers” of cloud computing—goes a long way toward identifying some of the nuances of the cloud’s sustainability claims. Part of the problem is that not all clouds are created equal. In addition to terrestrial computing, there are private clouds (bringing to mind the Rolling Stones’ “Hey, you, get off of my cloud”) and public multi-tenant clouds. Think of Apple’s iCloud, Amazon’s Cloud services, Google, etc., as the exemplars of multi-tenant cloud computing. The white paper, Salesforce.com and the Environment: Reducing Carbon in the Cloud (link opens PDF), commissioned from WSP, looked at Salesforce.com’s multi-tenant cloud and found:
  • A salesforce.com transaction is on average 95% more carbon efficient than when processed in an equivalent on-premises deployment;
  • A salesforce.com transaction is on average 64% more carbon efficient than when processed in an equivalent private cloud deployment; and
  • Salesforce.com’s estimated total customer carbon emissions footprint for 2010 is at least 19 times smaller than an equivalent on-premises deployment, and is 3 times smaller than an equivalent private cloud deployment.
Furthermore:
Salesforce.com’s cloud platform enables much higher utilization of servers; uses elastic provisioning to better match server capacity to demand; and applies multitenancy to serve thousands of organizations with one set of shared infrastructure. Further, salesforce appears to be leading the way in designing, building and operating cloud service hubs that minimize energy use for a given amount of computing power (not only at an operational level). Further, they can employ energy-saving innovations at a scale that only the largest on premises or virtualized data center owner / operators could feasibly manage.
Le secret, as this GreenBiz article points out, is looking at carbon emissions per transaction, which provides a standardized way of comparing the various clouds and terrestrial infrastructures. It’s a welcome relief that the sustainability of electronic media is finally starting to take center stage, rather than everyone just assuming there’s nothing wrong with them at all, and improved methodologies will only create a better understanding of the real environmental impacts of evolving technology trends, and identify where there is room for improvement. After all, we’re going there anyway—it behooves us to understand what the consequences are. UPDATE: Meanwhile, in today's Environmental Leader: "Salesforce Worst of ‘Dirty’ Cloud Companies, Greenpeace says." Conflating these two stories, I'm reminded of the old joke about the two women in the restaurant: one says to the other, "The food here is terrible." "Yes, and such small portions."