The Story Behind Google's Huge Appetite for Energy

Google this week dumped a massive amount of data about how much energy it uses (a lot), and how efficiently the company uses it (quite).

As per usual with Google, the news came out via a blog post, this one from Urs Hoelzle, Google's Senior Vice President of Technical Infrastructure, who writes in part that, "For the last decade, energy use has been an obsession."

Hoelzle's post, lifting the curtain on a broad new Google Green site, followed an earlier report this week that spelled out how using Gmail is 80 times less carbon-intensive than using other email services, because of how efficiently Google runs its data centers.

To follow on that peek inside its data centers, Google published a comprehensive and downright pretty (especially from a company that has been criticized as letting its visual design live or die "strictly by the sword of data") website that digs into the company's overall footprint, and breaks it down by each of the company's main areas of activity: Search, services (YouTube & Gmail) and the corporate campus.

In short: Google uses 2.6 million megawatt-hours of electricity, or enough to power 200,000 homes.

That's about 1 percent of all the energy used by all data centers in the world, or .01 percent of all the world's energy use. A small number, but that's still a lot of energy for one company to be responsible for.

And Google defends its massive carbon footprint -- 1.46 million metric tons of carbon dioxide emissions in 2010 -- by saying that 1) its data centers use half as much energy as competitors, because of Google's singleminded focus on energy efficiency; and 2) it's making all of its users (i.e. everyone) greener, again by way of that focus on efficiency, as well as replacing other carbon-intensive needs.

For example, watching 72 hours of YouTube has the same carbon footprint as the entire lifecycle of a DVD -- which, unless you're watching one of the Lord of the Rings DVDs one time, or watching any other video many, many times, means streaming video is a net positive.

Similarly, a year's worth of Gmail usage has a smaller carbon footprint than the entire lifecycle of a bottle of wine -- from growing the grapes to drinking the wine to, as Bill Wiehl, Google's Energy Czar, explained in an interview today, sending off a message in the now-empty bottle.

I asked Wiehl if there were any surprises that he and his team found in creating the new site, and he said that the act of making those kinds of data visualizations together was one of the big surprises.

"I've believed for a long time that taking activities that we have typically done in the past phyiscally, like mail or shopping, doing those online can save an enormous amount of energy," Wiehl said, "but actually quantifying it was very eye-opening."

Next page: Is a Google CSR report the next step?