Given that Google's proprietary server designs are key element to their business, its not all that surprising that the details would be a secret. What is surprising, is that they finally spilled the beans.

Google Finally Declassifies Some Key Server Design Secrets

Speaking at the Google "Data Center Efficiency Summit" yesterday, server designer Ben Jai showed off one of their data centers and custom web servers. To the audience's surprise, each server features a 12V battery as a backup should any problem occur with a main power source. They also learned that their data centers are housed in standard shipping containers packed with 1,160 servers and a power consumption that can reach 250 kilowatts.

Google Finally Declassifies Some Key Server Design Secrets

Essentially, the major advantage with Google's servers are that they are way ahead of the curve when it comes to energy efficiency. Jai notes:

Large UPSs can reach 92 to 95 percent efficiency, meaning that a large amount of power is squandered. The server-mounted batteries do better, Jai said: "We were able to measure our actual usage to greater than 99.9 percent efficiency."

To put that in perspective, right now Google is reaching levels of efficiency that the EPA hopes will be attainable in 2011 using "advanced technology." That's pretty extraordinary, but one has to wonder why Google is unveiling this now. Officially they feel that opening up will help other businesses in a dire economy focus more on efficiency—although Jai noted that Google was already on it's 6th or 7th generation of the server design, so my guess is that they are confident that they will remain ahead of the curve. Check out CNET for the full details. [CNET]