This report draws on a survey of wind industry professionals to clarify trends in the expected useful life of land-based wind power plants in the United States. Researchers at DOE’s Lawrence Berkeley National Laboratory found that most wind project developers, sponsors, and long-term owners have increased project-life assumptions over time, from a typical term of ~20 years in the early 2000s to ~25 years by the mid-2010s and ~30 years more recently. Current assumptions range from 25 to 40 years, with an average of 29.6 years.