‘It was our Manhattan Project’

CNET, on Google’s server hardware:

Typical data centers rely on large, centralized machines called uninterruptible power supplies (UPS)–essentially giant batteries that kick in when the main supply fails and before generators have time to kick in. Building the power supply into the server is cheaper and means costs are matched directly to the number of servers, Jai said.

“This is much cheaper than huge centralized UPS,” he said. “Therefore no wasted capacity.”

Efficiency is another financial factor. 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.”

The Google server was 3.5 inches thick–2U, or 2 rack units, in data center parlance. It had two processors, two hard drives, and eight memory slots mounted on a motherboard built by Gigabyte. Google uses x86 processors from both AMD and Intel, Jai said, and Google uses the battery design on its network equipment, too.

Efficiency is important not just because improving it cuts power consumption costs, but also because inefficiencies typically produce waste heat that requires yet more expense in cooling.

That’s some pretty sweet engineering.