The 310 megawatt facility at Lake Turkana in Kenya was initially set for completion in 2017, after which Google had committed to buy the stake.
Instead, it only becoming operational last year.
A spokesman for Vestas said the delay led Google to the cancellation of the deal and that the company is now in talks with other potential buyers.
Google was not immediately available for comment.
The wind farm is intended to reduce energy costs and move Kenya closer to its ambitious goal of 100% green energy by the end of next year.