When Infosys, one of the world's largest IT companies, was looking for ways to reduce the energy consumed by its 130-plus facilities, it wanted to explore radiant cooling, a technique that uses circulating water in embedded pipes to chill rooms.

At first, Infosys couldn't find any engineers in its home country of India willing to try it because they said it wouldn't work in the country's climate. To prove them wrong, Infosys took a building and split it in half so that one side was cooled by air conditioning and the other by radiant cooling.

The radiant cooling side, said Rohan Parikh, Infosys' head of green initiatives and infrastructure, ended up costing 40 percent less to operate. "We've now proven to everybody," he said, "that there is a technology that is better."

Radiant cooling is just one of the unconventional tactics Infosys has used on its way toward an ambitious goal to be carbon neutral by 2018.

Infosys' efforts also have included backing untested or expensive technologies to make them more mainstream, and it soon hopes to share the details of its efforts with other companies.

To meet its carbon-neutral goal, Infosys has three main paths: energy efficiency in buildings, renewable energy for what can't be reduced and carbon offsets for travel emissions.

Infosys started metering all of its buildings so it could get a solid grasp on where it was using the most energy. It first moved from getting monthly data on energy use to getting daily data, and then began submetering to see how much energy its computing, lighting, air conditioning and other systems were using.

"I think that was the best thing we did, because we ended up with very granular data," Parikh said.

The company found that buildings are its biggest carbon culprits. While all of the computing that Infosys does uses 40 percent of its energy, air conditioning also uses 40 percent and lighting accounts for an added 15 percent.

Infosys, which boasts revenue near $7 billion, has approximately 150,000 employees and adds more than 20,000 new hires a year. "To manage our growth, we need to add a lot of campuses," Parikh said.

In late 2007, he said, the company decided to act as a leader on greener buildings, a goal helped by the fact that Infosys owns -- rather than leases -- all of its facilities, meaning that it has full control over their design and operation.

"If we can do the right thing, we can put peer pressure on others and make then do the right things and make the right commitments," Parikh said.

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