Wind Turbine – Bird and bat conflicts
Wind Turbine – Bird and bat conflicts The first in a series, October 2015
Many of us live in states that promote wind turbine farms as a source of energy for the masses. Many states rely more and more on clean energy sources such as wind. With this technology, a conflict with birds and bats has occurred. It only makes sense that proper planning considers an overall environmentally sensitive approach; both for clean energy and for a coexistence and protection of wildlife.
This blog post addresses, in a broad brush approach, a few techniques being used in US states that allow a co-existence of manmade turbines with flying wildlife. Hopefully this generates additional discussion, illuminates techniques and inspires readers to encourage local providers to ensure care in planning, design and construction of these facilities. Please feel free to respond to this post with additional comments or questions. Experts on the subject matter (which I am definitely not) are welcome.
Additional information on this topic and others will surely be provided in subsequent posts from outtherealive.com.
In many cases, wind-wildlife conflict mitigation techniques have been derived after fields of turbines have been installed. And individual turbines are becoming larger (a future anticipated 1.5 acre per unit rotor swept area) for greater efficiency. One factor is that of turbine locations resulting in direct collisions with birds. Bats are also often a victim of direct collisions as well as rapid pressure changes, causing severe internal organ damage.
Turbines have been installed in major flight paths for migrating birds. Often in these situations, birds may fly lower than normal to avoid fog or a storm. Initial site analysis can result in an avoidance of these zones, in proper shutdown/slowdown mechanisms, in proper propeller sizing or a combination of these mitigation techniques. Proper planning may allow the removal of smaller turbines in lieu of fewer, larger turbines in locations outside of sensitive areas.
Map courtesy of birdnature.com
A few techniques that have been used and that will be explored in subsequent blogs include:
- BirdMap GIS-based mapping that uses US NEXRAD (WSR-88D) weather radar network to provide current and historical avian population density and seasonality data
- Auditory techniques including ultrasonic transmitters for bats and the ability to detect incoming bird flight paths from miles away to regulate turbine speed.
- Seasonal periodic shutdowns of turbines in certain areas
- Location analysis and removal of high risk turbines
- Keep cattle away from turbines, considering that their dung attracts insects that birds may pursue.
- Fewer new turbines that generate more electricity per unit of a size that puts them out of typical bird flight height range.
One bright spot of hope lies in the fact that there is a current trend for power providers to have facility monitoring programs in place
The following are the online sources utilized for this blog: