Shadow Flicker

From Open Energy Information

A row of GE Wind 1.5-MW turbines at the Klondike wind Farm in Oregon. Photo from Paul Woodin, NREL 11920

Shadow flicker occurs when wind turbine blades cast shadows that move across the ground and nearby structures. People who experience shadow flicker for long periods of time are likely to find it annoying. However, shadow flicker is easily modeled and can generally be avoided with proper planning and siting. Because shadow flicker can be predicted and mitigated, many localities specifically address shadow flicker in local ordinances.[1] Wind developers have techniques to model the potential shadow flicker to neighboring homes and can site wind turbine towers to reduce the impact.[2]


Allen, M. (February 10, 2011). Understanding the Current Science, Regulation, and Mitigation of Shadow Flicker: Community Concerns and Mitigation Methods. Saratoga Associates. Accessed June 20, 2018.
This presentation discusses shadow flicker, its impacts to communities, and mitigation methods.

Lampeter, R. (February 10, 2011). Shadow Flicker Regulations and Guidance: New England and Beyond. Epsilon Associates, Inc. Accessed June 20, 2018.
This presentation provides an overview of shadow flicker limits, modeling requirements and guidance, and compliance.


  1.  "American Planning Association. Planning for Wind Energy"
  2.  "U.S. Department of Energy. Wind Vision: A New Era for Wind Power in the United States"