As our world continues to move online, the Internet must make room and the web must stretch.

For Google, which hosts countless websites, emails, documents, videos and more, that means more storage capacity, which means more data centers.

The Internet search giant took a big step in that direction Friday, revealing plans to double its previous investment in Berkeley County by spending another $600 million on the data center complex there.

The promised investment is the biggest in the state since Michelin promised $750 million in April, and the biggest in Berkeley County since Google’s last $600 million announcement in 2007.

Eric Wages, site operations manager, made the announcement in a Google-themed tent pitched in the field where the expansion facilities will rise. The assembled elected and economic-development officials and Google employees stood and applauded.

“Thanks,” Wages said, “I thought everyone would like that.”

He said Google hopes to start construction on a new data center, which will be the third on the site, “pretty much as soon as possible” and continue “over the next few years.”

Google, which keeps several aspects of its data center operations secret for competitive reasons, did not lay out any particular timeline or plan for the building or future development.

Even Google technicians who attended Friday’s event said they didn’t know the details of the future facility.

“We just know it’s a building,” said Ryan Spindt, a 24-year-old Goose Creek resident.

Wages said no permitting applications had been filed yet, in order to preserve Friday’s surprise.

A Google spokeswoman declined to say whether Google has already spent the original $600 million.

Google did not say how many jobs the expansion will bring to 1669 Garrott Ave., just that the positions will include facilities managers, network engineers, computer technicians and security personnel.

But for the first time, the Mountain View, Calif.-based company revealed there are about 150 employees at its two existing data center buildings. Wages also announced for the first time Friday that the second data center is now handling web traffic.

Calling South Carolina “such a cool state,” Gov. Nikki Haley said “having Google is an absolute feather in our cap.” She credited the legislation passed last year that exempts data centers from taxes on their massive electricity usage and on their purchases of computer hardware and software.

“So this Googler,” Haley continued, referring to herself, “along with every Googler across this state should be proud. Remember that every time we jump on that computer, it happens because of places like this.”

The company’s interest in expanding South Carolina dates back more than seven years. A company linked to Google bought the more than 500 acres off U.S. Highway 52 for $17 million in December 2006.

In April 2007 the company announced it was building a data center complex there, with the major attractions being cheap water and power.

Google opened its first facility there in 2008 and recently opened the second one next door as part of a combined $600 million investment. The field to the south where the third facility will sit was also cleared in 2007.

The company was offered job development credits then but did not accept them, an S.C. Commerce Department spokeswoman confirmed Friday, in part because the site still hasn’t reached the minimum 200-job threshold.

Google did not seek additional discretionary incentives this go-round, according to the company and Amy Love, the Commerce spokeswoman. Berkeley County officials did not respond to calls about what incentives Google received on the local level.

Joe Kava, Google’s senior director of data-center construction and operations, had hinted at the expansion in November as part of a campaign to lift the veil on the company’s secretive server farms.

“We do have a lot of flat open space there, which makes it a great site for continued growth,” he told The Post and Courier two months ago. “When we invest a lot of energy in finding the next Google data center campus, we want this to be something we can count on for a long time.”

The local data center complex, along with a dozen others around the world, houses high-tech hardware, wiring and other electronic components to support services such as Google search, Gmail, Google+ and YouTube.

Virtual bits of data like e-mails, videos and programs are saved on servers at the site.

Data centers have recently faced criticism for being inefficient in their use of power and water, but Wages emphasized Friday the Berkeley County site’s focus on being energy-efficient and environmentally friendly.

That includes experimenting with using rainwater to help cool the servers inside. The stormwater collection pond, which sits to the north of the first data center, is home to a four-foot alligator named Allie.

Media were not allowed inside the buildings Friday, but according to previous Post and Courier accounts and photos Google has published, they are mostly filled with servers, with only a small portion allotted to colorful office space.

Security is tight outside, too, where nearly seven miles of fencing surrounds the site, and guards control access and patrol the roads.

Google has been more open in sharing its tech savvy and money with the local community. The company has hosted training events for local small businesses and nonprofits and sponsored free wireless Internet in part of Goose Creek and in Marion Square in downtown Charleston.

Asked what the expansion would mean, Catherine Yu, another data center technician, answered nontraditionally.

“Hopefully more dogs,” said Yu, a 29-year-old North Charleston resident, holding her pug mix, Sparky.

“With expansion comes more dogs,” Spindt added authoritatively.

Reach Brendan Kearney at 937-5906 and follow him on Twitter at @kearney_ brendan.