Managing 14 separate, inefficiently designed datacenters spread throughout a city is difficult and costly enough. Add to that an unreliable primary energy supply that drops off frequently and abruptly, and you've got a huge headache.

Those were the problems plaguing Hewlett-Packard's datacenter test labs in Bangalore, India, where the power delivery from the local utility is spotty at best. The norm, in fact, is for buildings to have backup diesel generators that fire up periodically. "The diesel engines come on a lot. We want to minimize that. We want the diesel truck to come as few times as possible," said HP Fellow Chandrakant Patel.

[ Discover the techniques used by other 2008 Green 15 winners to make their IT more sustainable. ]

The solution: First, Patel directed the consolidation of the 14 far-flung Bangalore facilities into a single, efficiently laid-out 70,000-square-foot space, containing a heterogeneous environment of older equipment and newer server racks and blades. Next, his team installed a 7,500-sensor smart cooling system. The sensors monitor the temperatures of the machines on rack-by-rack basis and adjust cooling to meet local needs.

Less power, less cost -- and no jackets required
This approach eliminates the need to blast air conditioning throughout an entire datacenter. That's key because blast cooling not only results in a meat-locker-like climate but is a significant, wasteful cost. When the new cooling system went online, the datacenter's energy consumption dropped 20 percent, Patel said, and has approached 40 percent after further optimization -- for an annual savings of around 8,400MWh, or about $2 million.

The benefits of the project don't stop at energy savings, either. The atmosphere is spared a large chunk of carbon emissions. Another benefit: Since the project's completion, downtime has dropped significantly when the facility is forced to switch to backup generators as the local utility comes on and offline. That's because the new cooling system's lower power usage has reduced the loads when the generators kick in, so they don't trip as they used to.

Remote management reduces travel
The nature of the sensor-based system yields another key benefit: Patel and his team can monitor and manage the Bangalore cooling system from HP's headquarters in Palo Alto, Calif., as they receive the data from the sensors in real time. That means they don't need to hire and teach someone the advanced skills to do it in India -- reverse outsourcing, Patel called it.

In fact, he said they were able to turn the system on remotely and commence optimization without anyone having to travel overseas. (That's not only convenient, but reducing air travel adds yet another green layer to the project.) "Our original plan was to send the whole team to India, but flying back and forth seemed like an expensive proposition. So we did it remotely," he said.