The project is in the Texas Panhandle, 56 kilometres (35 miles) from Amarillo and uses Siemens 2.3MW turbines. It came online at the end of last year.
Spinning Spur was developed by EDF Energy. Google did not reveal the size of the equity stake, although it has tended to acquire minority stakes in projects.
In November, Google took its investment in the renewable energy sector to more than $990 million when it announced a $75 million equity investment in the 50MW Rippey wind farm in Greene County, Iowa.
Other Google wind project outlays include the $55 million investment in the Alta Wind Energy Center in California.
The internet giant is also a major investor in a $5billion Atlantic Wind Connection transmission project designed to connect offshore wind farms along the Atlantic coast.