There has been some debate here on ZDnet in the past few months over the energy efficiency profile of the cloud, especially since Greenpeace came out blasting the high-tech industry at large for not thinking through the power equation properly.
So, it is perhaps natural that one of the keynote presentatations during the opening day of the Uptime Institute’s Symposium 2010 here in New York focused on the “Power-Related Advantages of Cloud Computing.”
According to Jonathan Koomey, who is a consulting professor for Stanford University and a project scientist at the Lawrence Berkeley National Laboratory, there are four primary reasons why cloud computing (at least philosophically speaking) should be a more power-efficient approach than an in-house data center. This is the order in which Koomey lists them.
- Workload diversity: Because you will have many different sorts of users making use of the cloud resources – different applications, different feature set preferences and different usage volumes – this will improve hardware utilization and therefore make better use of power that you’re using anyway to keep a server up and running.
- Economies of economies of scale: There are certain fixed costs associated with setting up any physical data center. According to Koomey, implementing technical and organization changes is cheaper per computation for larger organizations than for IT small shops. And because you will have more people using the infrastructure, again, you can spread those costs more efficiently.
- Power-management flexibility: Koomey postulates that it’s easier to manage virtual servers than physical servers from a power perspective. If hardware fails, the load can automatically be deployed elsewhere. Likewise, in theory, you could move all virtual loads to certain servers when loads are light and power-down or idle those that aren’t being used.
- You can pick the most efficient site possible: So, for example, if you are a business based in a state that uses primarily coal-powered electricity, do you really want to site your data center there? “If you have a data center in a place that is all coal-powered, this is a big business risk,” Koomey says. In a future where there might actually be a tax on the carbon your company produces, that would certainly be a risk indeed.
The 451 Group, which is now part of the Uptime Institute, has published a separate report on IT and the greening of the cloud. The point being that none of you should forget about power considerations when you're evaluating a cloud service provider, even if you are "just" an IT manager.