Google is spending $600 million on a new data center in Iowa.

The facility, already under construction, is expected to open in the first half of 2009.

So far, Google is planning on two buildings to house its server farms at the Iowa site but has acquired more land for potential future growth. The search giant said it has no definite plans for expansion in the future though.

Google is interested in placing data centers in the middle of the country because it is a "busy crossroads of Internet activity," it said in a statement.

It recently said it would make the same size investment each in similar new data centers in Oklahoma and North Carolina. All the facilities will employ around 200 workers.

Early last year, Google began scoping out potential locations in "states from the Appalachians to the Rocky Mountains" for new data centers, it said.

As companies like Google offer an increasing number of Web-based applications, they need to build more server farms to support the services. Google is notoriously secretive about locations it may choose for its data centers and about the precise contents of the facilities. It has said that it often builds its own servers to save on the expense of buying branded off-the-shelf machines.