Google Data Centers Use A Lot Of Hot Air

Google likes a lot of hot air.

This is not a sophomoric rejoinder at the speaking proclivities of Google’s marketing staff or its legal team. Rather, its a literal statement.

When heated by the Sun, hot air rises, and in its place, cooler air will blow in to fill the void, which is where we get wind. And wind is something with which Google is making a great deal of use to power the needs of its data centers and offices. Nowhere was this more evident than yesterday’s announcement of Google’s commitment to purchase 240 megawatts (MW) of power generated by the Happy Hereford wind farm near Amarillo, TX.

The wind farm will feed into the Southwest Power Pool, the grid that serves Google’s Mayes County, OK data center, according to Matt Pfile, Senior Manager, Data Center Energy and Location Strategy.

In the announcement, Pfile mentioned that with this agreement, which is expected to start producing energy for Google in 2014, Google consumes “more than 570 MW of wind energy, which is enough energy to power approximately 170,000 U.S. households.”

That’s a lot of houses, to be sure. That’s about half of the households in my state capital of Indianapolis, and 0.15% of the total U.S. household number.

But out of curiosity, how many servers would that much energy power?

Coincidentally, XKCD artist Randall Munroe just happened to do the legwork that could help answer this question in this week’s installment of What If? XKCD. The site takes on the answers to such questions as how long would it take to drain the oceans, what would happen to a Sunless Earth and when the Sun finally set on the British Empire.

This week, Munroe answered the question of how many data punchcards would be needed to match the amount of data Google stores. Among his educated guesses, Munroe needed to answer the question of how many servers Google has, and he did so by figuring out Google’s known energy consumption and using a base figure for per-server power consumption: 215 W.

Presuming Munroe’s assumptions are correct—and they would seem to be very much in the ball park—then that means that if Google uses all of that wind power for servers in its data center, then it would be powering 2.65 million servers on wind energy alone.

Which is a lot of hot air.