Scientists at the University of Calgary have found a way to reduce bat deaths from wind turbines by up to 60 percent without significantly reducing the energy generated from the wind farm. The research, recently published in the Journal of Wildlife Management, demonstrates that slowing turbine blades to near motionless in low-wind periods significantly reduces bat mortality.
"Biologically, this makes sense as bats are more likely to fly when wind speeds are relatively low. When it's really windy, which is when the turbines are reaping the most energy, bats don't like to fly. There is a potential for biology and economics to mesh nicely," says U of C biology professor Robert Barclay, who co-authored the paper with PhD student Erin Baerwald of the U of C as well as with Jason Edworthy and Matt Holder of TransAlta Corporation.
Last year, a groundbreaking Barclay-Baerwald study shed new light about the reasons for bat deaths under wind turbines in the Pincher Creek area. Researchers found that the majority of migratory bats in this southern Alberta location were killed because a sudden drop in air pressure near the blades caused injuries to the bats' lungs known as barotrauma. Although the respiratory systems in birds can withstand such drops, the physiology of bats' lungs does not allow for the sudden change of pressure.
The next step was to find a way to mitigate the deaths. TransAlta, Canada's largest publicly traded provider of renewable energy, initiated a follow-up study at the same site to determine what could be done.
"Wind power has come of age, so further minimizing the impact of wind farms on the surrounding ecology is always important to our industry," says Jason Edworthy, director of Community Relations for TransAlta. "Working with the university during the course of this four-year study has given TransAlta the opportunity to test real world strategies that benefit affected bat populations and make economic sense."
Until recently, wildlife concerns regarding wind energy focused primarily on bird fatalities. But bat fatalities now outnumber those of birds due, in part, to efforts to mitigate bird deaths by wind turbines.
Most bats killed at wind energy facilities across North America are migratory tree bats, including hoary and silver-haired bats. The deaths occur during autumn migration from Canada and the Northern U.S. to the southern U.S. or Mexico.
"Given that more bat fatalities occur in low wind speeds and the relative ease of manipulating operation of turbines, we examined whether reducing the amount that turbine rotors turn in low wind speeds would reduce bat fatalities," says Baerwald.
Over the one-month experiment total revenue lost from the 15 turbines was estimated between $3,000 and $4,000.
TransAlta has already applied the low wind mitigation strategy to the 38 turbines identified in the study area. "The findings from the study area are promising and this new mode of operation is now in place and will be applied to new wind farms," says Edworthy.
"Although these are promising mitigation techniques, further experiments are needed to assess costs and benefits at other locations," says Barclay.
The journal article, A Large-Scale Mitigation Experiment to Reduce Bat Fatalities at Wind energy Facilities, can be found online at: http://www.wildlifejournals.org/
Related U of C story: http://www.ucalgary.ca/news/aug2008/batdeaths
Related Calgary Herald Story: http://www2.canada.com/calgaryherald/news/city/story.html?id=69b0a3a8-a833-4de3-a925-b135f837ded6
MEDIA CONTACT:Leanne Yohemas
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
23.03.2018 | Event News
19.03.2018 | Event News
16.03.2018 | Event News
23.03.2018 | Materials Sciences
23.03.2018 | Agricultural and Forestry Science
23.03.2018 | Physics and Astronomy