Google's 7-Step Program to Slash Your PUE by a Third

Google's 7-Step Program to Slash Your PUE by a Third

For years, the IT industry (and those of us in the media focused on green IT) have been dying to get a look inside Google's data center operations.

Slowly but surely, the company began raising the curtain on its efforts: A look at its custom server design here, a peek at its PUE efforts there, a presentation at a conference, and so on.

But this week, Google lifted the veil on its green IT operations in a big way (I'll have a longer take on the overall news later today after an interview with Bill Wiehl), announcing its carbon footprint and touting some of its many strategies for greener operations, in the data center and far beyond.

One element of this massive data dump is of particular interest to IT professionals: Its white paper on data center best practices.

In the 10-page document, Google walks us through their "Points of Presence" (POPs) -- Tier 3 data centers that it says are "similar to millions of small and medium-sized data centers around the world."

The white paper discusses in detail a retrofit project for one of its POPs, laying out three overall best practices for data center energy management:

1) Measure performance (i.e. Know your PUE) 2) Optimize airflow (i.e. hot- and cold-aisle containment) 3) Turn up the heat (i.e. set your thermostats to 81 degrees)

Google's engineers also walk through the detailed steps of their first level of immediate fixes -- installing sensors, optimizing air flow tiles, and the like -- their cold-aisle containment process, and their upgrades to the CRAC units, with details on how each step reduced the PUE of the facility.

In the end, the five Google POPs that are included in this white paper saw significant PUE drops -- about one-third for each facility -- through the following list of improvements:

1. Added temperature monitoring
2. Optimized air vent tiles
3. Increased temperature and relative humidity settings on CRACs
4. Blocked off the ends of cold aisles with curtains
5. Put blanking plates and side panels to block cold air passing through empty rack spaces
6. Added 48" extensions to all CRAC air returns
7. Added a new CRAC controller

Even more importantly, Google saw extremely rapid returns on its investments. The chart below shows just how quickly each of these projects paid for itself:

figure 1

Google's sharing this kind of leadership with the IT industry goes a long way toward justifying their larger claims of making the world greener. But I'm curious to hear what your thoughts are on Google's 7-step program, or other ways you've squeezed more efficiency out of your data centers. Let me know in the comments below or by email.