The announcement came little more than six years after the California-based Internet search giant broke ground at its 215-acre site in the North Carolina foothills. At the time, the company said it hoped to expand on its initial $600 million investment. North Carolina Gov. Pat McCrory and other officials on hand for Friday's groundbreaking said the construction of a third building on the campus underscores Google's long-term commitment to western N.C.
"It's great news for Caldwell County and our state," McCrory said.
Officials said the news solidifies the area's reputation as the epicenter of the state's growing data center corridor. Apple has a data center in Maiden, N.C., and Facebook has one in Forest City, N.C.
Jeff Branch, chairman of the Caldwell County commissioners' board, said Google's growing presence shows how the area once known for furniture and manufacturing can now count itself a player in the fast-growing digital sector.
"In a county like ours, Google can make a big difference," he said.
Added Lenoir Mayor Pro Tem T.J. Rohr: "Suddenly working in technology isn't just something a guidance counselor talks about. It's a career you can have and stay here in Lenoir."
The expansion is part of a renewable energy program from Charlotte, N.C.-based Duke Energy for large customers.
Duke plans to make a regulatory filing with the N.C. Utilities Commission within 90 days, seeking approval for a new rate structure that would encourage large consumers like Google to use renewable energy, said Paul Newton, Duke Energy state president.
Google and other data companies use vast networks of computer servers in their data centers, all of which require massive amounts of power. Google's Caldwell County center houses systems that support Google search, Gmail, the Google+ social network and YouTube.
"As more of the world moves online, demand for Google's services continues to grow," said Gary Demasi, director of Google's global infrastructure team. "We want our renewable energy options to grow with it."
Owners of power-hungry data centers have been under growing pressure from environmental groups to use clean energy.
The New York Times reported in 2011 that Google's data centers sucked in almost 260 million watts, or about a quarter of the output of a nuclear power plant, to run its searches and other Internet services.
Google said in a news release that it operates some of the world's most efficient data centers, consuming 50 percent less energy than typical centers. It has announced a goal of becoming a "carbon neutral" firm, and seeks ways to maximize its use of renewable energy sources.
Apple says its data center in Maiden, 30 miles northwest of Charlotte, makes enough renewable energy to displace all the facility's power usage. The energy it produces goes onto the electric grid.
The company completed a 20-megawatt solar farm next to the center in 2012 and expects a second 20-megawatt farm to go online late this year.
Apple also built a 10-megawatt fuel cell installation that runs on natural gas. In all, the company says its renewable facilities in Maiden produce enough energy to power 17,600 homes for a year.
Greenpeace, a critic of data centers and of Duke, said Friday's announcement "shows what forward-thinking companies can accomplish when they are serious about powering their operations with clean energy."
"It's good news that Duke is beginning to heed their major new customers' demand for renewable energy sources," Gary Cook, a Greenpeace IT analyst, said in a statement. "Done right, this Renewable Tariff program could help North Carolina finally begin to realize the benefits of a clean energy revolution, which Duke has blocked in the past."