Wind turbines overall kill some 573,000 birds per year including 83,000 birds of prey. (1) Yet in December 2013, the Obama Administration announced an extension of the existing five-year eagle take permit. Effective immediately, the new rule issued by the Department of Interior will grant 30-year permits allowing wind farms to 'accidentally kill federally protected eagles,' The 'rule' is in direct violation of the Bald and Golden Eagle Protection Act passed by Congress in 1940. As Marita Noon says, “once again, executive action trumps the law.” (2)
The Audubon Society and other wildlife advocates are furious, depicting the move by the Department of Interior as a license for indiscriminate killing. The irony is that the Audubon Society and other bird advocates have previously supported so-called 'take permits' for wind farms and other companies that might harm eagles, albeit for a five year period, not 30 years. The problem is that the earlier system had no teeth. The only incentive for energy companies to participate was to escape prosecution under the Bald and Golden Eagle Protection Act. Only one wind farm operator, Duke Energy of Wyoming, was ever prosecuted. The company recently agreed to pay $1 million for killing 14 eagles and149 other birds at two Wyoming wind farms, reports Peter Fimrite. (3)
Bats also suffer. Wind turbines killed almost 900,000 bats last year alone, a species that the US Geological Society (USGS) estimates provide about $23 billion in benefits to America's agricultural industry each year. (4)
Some who work directly with the wind industry to reduce bird and bat deaths at wind facilities have described the industry's response as 'mixed' and unsustainable.' One might ask how come someone hasn't developed bird safer wind turbines?
Turns out there is some work being done. Altamont Pass, which has one of the largest concentrations of wind farms in the country, is in the middle of a decommission of 4,000 old turbines that use 1970's and 80's technology; nearly all will have to be removed or replaced by 2018. The world's most heavily studied area for wildlife impacts could also be the proving ground for a new type of turbine that county officials and ecologists hope will be less deadly. The replacement will be a new 'shrouded' wind turbine design. Compared with more familiar wind turbine designs, the shroud offers a visual and physical obstacle to discourage birds from flying into the rotor blades. The key is the shroud—two concentric covers around the blades—which supposedly not only makes them more efficient than older turbines, but also less accessible to approaching birds and bats. At less than 200 feet, they're shorter and smaller than turbines which can reach almost 500 feet, reports Jeremy Thomas. (5)
Besides this, there are reportedly a number of different kinds of other 'animal friendly' wind turbines that operate on a slightly different working principle than long blades to achieve an efficient energy yield.
Here are some of the alternative designs:
INVELOX- SheerWind Inc. has patented INVELOX, a system that takes the spinning blades of a turbine out of the sky and puts them safely at or below ground level, eliminating the risk for harming eagles or any wildlife. It also puts an end to the issues from low frequency airborne vibration from the large turbine blades that have a negative influence on humans, wildlife, and livestock. (6)
According to SheerWind's publicity, INVELOX technology has been reviewed and validated by a technical advisory board, and a team of experts from major research universities and agencies. Prototypes were tested under controlled laboratory conditions, and test results were used to build and validate full-scale computational fluid dynamic models. Field data collected to date have validated results. (6)
SheerWind claims that its INVELOX is six times more efficient than regular turbines. As Ryan Whitwam observes, “the company is trying to prove its case but it's currently doing so with internal testing, so keep that in mind.” (7)
EWICON- Dutch researchers have created a bladeless wind turbine with no moving parts that produces electricity using charged water droplets. While most wind turbines generate electricity by converting kinetic energy into mechanical energy of the blades rotating, which in turn generates electrical energy, the EWICON (Electrostatic WInd energy CONverter) creates electrical energy directly from wind energy.
The EWICON's advantages include the facts that it can come in may different shapes and sizes and it has no moving parts, meaning much less mechanical wear and tear and thereby maintenance costs. Thanks to the lack of moving parts, it is also much quieter and creates fewer vibrations, making it suitable for urban settings. So far, researchers at Delft University have only made a few small-scale working prototypes of EWICON, however, the team is seeking funding to build a larger model. (8)
Compressed Air Enclosed Wind Turbine- World War II veteran Raymond Green, an 89 year old resident of Jackson, CA, has created a working prototype of a 'bladeless' wind turbine which is claimed to be bird and bat-friendly, and very quiet in operation. Green's design utilizes no exposed turbine blades, but instead a form of air compression cone technology. (9)
Though still in development at present, Green intends his design to be produced in various sizes, from smaller personal versions to much larger turbines which could be implemented in wind farms.
Pete Danko questions this design and quotes Paul Gipe, a respected writer on wind power who said this about the design, “It's not original. It's not new. It's not significant in any way. It will be gone in a few years.” (10)
The Screw Turbine- TESNIC's screw type turbine has screw shaped blades that harvest most of the wind, while the air inside the screw boosts its spinning power. The spinning screw turbine appears as a fuzzy wall, so it is quite unlikely that animals would try to poke their noses into it as it operates. They also won't fly into something that looks like a solid obstruction. (11)
The Parabolic Dish Turbine- Developed by Saphon Energy, the wind turbine is shaped like a parabolic dish. It uses 'sails' that make up the body of the wind turbine. As the wind blows, the sail is moved back and forth, following a path that allows the conversion of kinetic energy using pistons. Because it does not have any blade of some sort, it is perfectly safe for flying animals. (11)
So, a lot of folks have been working this issue, but to date, it isn't obvious that a successful full-scale design has been found.
A number of reviewers have criticized some of these designs with interesting comments;
- Too bad that physics says that the longer the turbine blades are the more efficient the wind turbine gets.
- If people really cared about bird strikes, they'd get serious about painting turbines purple, which makes them stealthy to insects, and thus not worth the risk for hunting birds.
One last note- my thanks to Alice Ansfield for suggesting this topic and providing a number of references.
References
- Robert Bryce, “Fighting climate change by killing eagles,” The Wall Street Journal, October 11, 2013
- Marita Noon, “Death by Renewables,” Canada Free Press, December 16, 2013
- Peter Fimrite, “Eagle deaths split wind-farm debate,” San Francisco Chronicle, December 10, 2013
- Travis Fisher and Alex Fitzsimmons, “All trick, no treat: how wind turbines kill bats and hurt farmers,” Canada Free Press, October 30, 2013
- Jeremy Thomas, “Researchers, companies seek safer turbines,” Bay Area News Group, January 2, 2014
- “SheerWind's wind towers won't harm eagles,” sheerwind.com, December 7, 2013
- Ryan Whitwam, “Bladeless, funnel-based wind turbine claims huge efficiency gains,” geek.com/science, May 12, 2013
- Olivia Solon, “Bladeless wind turbine produces energy with no moving parts,” wired.co.uk, April 3, 2013
- Nicholas Brown, “Bird-safe wind turbines may soon take flight,” cleantechica.com, September 4, 2012
- Pete Danko, “Why 'breakthrough' wind turbines are usually bunk,” earthtechling.com, September 5, 2012
- Christian Crisostomo, “Bird and bat-friendly wind turbines,” theenvironmentalblog.org, September 9, 2013
