Patent Application
20160044910
This application is related to two other copending applications. All three applications were filed on the same day, Aug. 12, 2014; all three titles are listed below. All applications were invented by the same person; in addition, there are two additional named inventors of the last of the following listed applications.
The application numbers of the above were not available at the time of filing. The two copending applications are incorporated herein by reference in their entirety. All of the aforementioned Applications were filed identically except for the Titles, Paragraph [0021_] (e.g., [0021A]), Claims, and the ABSTRACT. The second of the aforementioned Applications includes additional Paragraphs [0002B] and [0003B]. The commonality of this approach was done to ease the examination process as they employ common BACKGROUND, SPECIFICATION and FIGURES sections which use many common features and descriptions, etc. (baring the noted exceptions).
This invention relates to reducing or eliminating harm to birds, when they otherwise would impact wind turbine blades found at wind turbine power units.
Wind turbine power units are commonly used in the United States and throughout the world to off-set electricity generation from fossil-fired power plants. Given the same consumption of electricity by the public, the use of wind turbines obviously reduces global greenhouse gas emissions. However, environmentalists and the general public are increasingly objecting to the destruction of birds when they fly into the rotating blades of wind turbines. In advocating the further use of wind turbine power units, the harm to birds must be reduced. In a very real manner, said reduction would have a positive impact on reducing greenhouse gas emissions, promoting the use of a renewable resource, and would make wind turbines more readily acceptable to the public. No inventor knows of any prior art related to the sustained prevention or sustained reduction of harm to birds caused by rotating wind turbine blades
A 2004 article written by a USDA Wildlife Services employee sates that the typical noise generator, intended to frighten birds, was shown not to have lasting affects unless drastic measures were taken (i.e., killing birds). The reference for this article is: Robert C. Beason, “What Can Birds Hear?”, Proceedings of the 21st Vertebrate Pest Control Conference, RM Timm & WP Gorenzel, Editors, Published at University of California, Davis 2004, pages 92-96. This article does not mention wind turbines; it does not mention solar thermal power plants; it does not mention any other power plant type. The relevance of the article lies only with its assurance that birds learn to ignore noise which being becomes common place to them; unless drastic measures are taken (i.e., killing birds) and when accompanied by an appropriate annoyance. This invention directly addresses this problem.
This invention teaches how to reduce the destruction of flying birds caused by power plant units using renewable energy resources; for example such as wind turbines. Three embodiments are presented. The first embodiment is an apparatus which employs a noise-making apparatus placed on one or more turbine blades to frighten birds away from the turbine. Its operation comprises using the air stream relative to the blade, the stream being created when the turbine blade rotates, a noise-making apparatus having an air intake, such as a whistle. Further, the apparatus is so constructed as to produce a variable frequency, varying as a function of both position on the turbine blade, its rotational speed, and the angle of attack relative to the wind velocity. The noise-making apparatus's outlet is directed ahead of the turbine to frighten birds. Note that as the local wind changes velocity the noise-making apparatus is designed to change frequency. The advantage of this embodiment is that it is passive: as the blade turns a noise is produced.
A second embodiment is a method comprising an active electronic system in which sonic, ultrasonic or radar waves are used to detect, then frighten away, one or more in-coming birds whose un-interrupted path would otherwise intersect with dangers associated with power plant units using renewable energy resources (i.e., blades on a wind turbine power plant unit, or the high energy flux produced at a solar thermal power plant unit). The said in-coming birds are “targets” to the electronic system. The target's course and speed would be identified, and action taken to divert paths. The action taken comprises directing noise or lights aimed at the targets to thus frighten them away from the power unit. The advantage of this embodiment is that it would only produce diverting noise or light signals when targets are identified, thus the produced noise and/or light image would have minimum impact on the local populace, they being used only intermediately. When applied at a wind turbine power unit, it is a system which does not interface with the blades proper. The apparatus is mounted near the central hub of the wind turbine, or near the solar flux, both in a static manner. For a wind turbine power unit, the “central hub” is sometimes referred to as the machine's nacelle. Given that functioning equipment associated with the power units is not impacted, the system is easily retro-fitted to existing wind turbine or solar thermal power units.
A third embodiment comprises a method and apparatus of an illumination system applicable to wind turbine power units. This system comprises of light sources which are directed to mirrors mounted near the ends of turbine blades with the result of creating various patterns of light visible ahead of the turbine. Such patterns of light are chosen to frighten birds away from the blades. Each blade has a unique source of light, said light source is mounted on the turbine's rotating hub. The emitted light would be reflected through mirrors to a point(s) ahead of the turbine. The resultant light pattern may remain static in the axial plan, presenting only rotating rays from each blade. If the light pattern is not visible enough to birds, a mist of water may be injected into the illuminated space thus accenting the light by diffusion. The advantage of an illumination system is that it makes no noise and may be turned on only when targets present themselves, thus reducing light pollution.
Teaching the implementations of the present invention is presented as one of three embodiments, all of which are discussed in the following paragraphs. Paragraph [0021] identifies the claimed Preferred Embodiment. The first embodiment, although simple to install, represents a ready solution, and an inexpensive solution, to the problem of birds flying into turbine blades associated with a wind turbine power unit. This embodiment is a noise-making apparatus mounted on the blade whose intake is derived from the air stream created when a turbine blade rotates. Its intake is parallel to the air's direction relative to its placement on the blade. For example if the noise-making apparatus is mounted on the blade's tip, it maybe mounted at an angle relative to the cord of the blade to achieve parallel flow with the air's flow as it is shed from the blade's tip. If mounted on the leading edge of the blade, the noise-making apparatus can be directed at an angle from the rotating axis such that the relative air velocity impacts the noise-making's intake as a parallel flow for maximum effect. Thus such mounting alters the noise-making apparatus's angle of attack relative to the wind velocity. The outlet horn of the noise-making apparatus is directed towards the front of the turbine; i.e., towards the bird's potential flight path. In general, noise-making apparatus of this embodiment consist of mechanical devices without moving parts other than a possible reed. Noise-making apparatus of this embodiment comprise: whistles, devices using reeds, devices using various lengths and sizes of outlet horns, and similar devices.
Since birds may become accustomed to certain frequencies, the noise-making apparatus and blade configuration of the first embodiment has an ability to produce various frequencies while remaining a passive device. This is intrinsically accomplished given that wind turbines often rotate at varying speeds and at different angles of attack relative to the wind velocity. Thus when a turbine encounters s variable wind velocity, the noise-making apparatus as attached to each blade produces variable frequencies.
The second embodiment comprises a method for producing a wave form (e.g., sonic, ultrasonic, radar waves, or like waves), a computer used to analyze return signals from said waves, and a method of activating an annoyance noise directed towards the birds which frightens birds thus diverting their course away from a power plant unit using renewable energy resources. As targets of the said waves, a bird or flock approaching the power plant unit, is detected via return waves as to the target's course and speed. Such technology is considered well established and known to one skilled in the art; it has been practiced and improved since the 1940s. The computer would analyze the input signals based on programming then make a decision as to potential collision with the power plant unit, and, if so, produce an output signal which would actuate a disruptive noise and/or light images which would frighten birds away from the power unit.
In addition, for the second embodiment, the computer may determine the most likely method to use for redirecting the bird or flock based on detected size, speed and/or flight pattern. The computer may have a data storage mechanism which aids in determining which disruption is best suited to frighten a given type of bird. Such data storage may be a function of bird size, type and/or flight formation patterns; e.g., geese tend to fly in “V” formations, ducks fly faster than geese, etc. The computer may also have the ability to decide if the action which was taken was successful, if not, then additional measures could be activated. It is a system which would not interface with any component associated with the power plant unit; it would be mounted in front of the power unit. The second embodiment has no moving parts. Given such static placement the system could be retro-fitted to existing power plant units.
The third embodiment is a method and apparatus comprising an illumination system which produces a light pattern ahead of the blades of a wind turbine power plant unit which disrupts a bird's flight pattern and thus reduces and/or prevents blade impact. This illumination system comprise a light source which is attached to the central hub (nose) of the wind turbine producing a light which is directed to a mirror also attached to the central hub. This mirror is termed the “hub mirror”. For every turbine blade there is a light source and hub mirror; the light source and hub mirror rotate in unison with each turbine blade. The light source and hub mirror combination are herein termed a “light sub-assembly” (the light source and hub mirror combination is detailed in
The fixed blade mirror of the third embodiment is positioned in a fixed manner relative to the blade. From the fixed blade mirror, the light then is reflected ahead of the turbine (e.g., to the vertex of a cone of light). The light source comprises a laser, or light in the visible spectrum, or a strobe light, or a source having similar functionality, or use of the sun's light. The fixed blade mirror has a fixed position on the blade to reduce the cost of blade manufacture, to eliminate the need for re-alignment or movement mechanisms. The hub mirror may be in a stationary position, both axially and rotationally. The hub mirror (or the entire light sub-assembly) may also move in the axial direction, that is closer or nearer to the turbine blade; if so moved, to then maintain light ray alignment with the fixed blade mirror, the hub mirror must be allowed to rotate (see
Further, the illumination system of the third embodiment may comprise a system in which all light sub-assemblies move in unison: back and forth relative to the turbine blade, but maintaining the same aiming points on the fixed blade mirrors. This requires the hub mirror (or light source) to tilt such that the fixed blade mirror is always hit with a ray from the light sub-assembly. This variation allows, for example, if the light shape is a solid cone, for the cone's vertex to move back and forth. As the light sub-assemblies are moved closer to the turbine blade, the cone's vertex moves away from the turbine. This action creates an image of an oscillating cone.
The third embodiment's use of a light sub-assembly, as described in the above paragraphs, also includes a light source aimed directly towards the fixed blade mirror. This variation thus eliminates the hub mirror, but also means that the light source, to maintain light ray alignment with the fixed blade mirror, must be allowed to rotate in a manner similar to that required if using a hub mirror (see
Further still, the illumination system of the third embodiment may comprise fixed light sub-assemblies, but for each blade the light sub-assemblies are fixed at different, staggered positions. Such staggered positioning will create a screw-like image ahead of the turbine which appears to rotate—a rotating screw. The advantage of this refinement is that, after alignment, it requires no moving parts, other than the moving turbine blades and each of their attached, and fixed, light sub-assemblies. As being moved with the rotational speed of the turbine, and especially if more than three blades are being used, this refinement results in an oscillatory rotating screw-like image which would scare a pterodactyl.
In summary, the Preferred Embodiment submitted for these inventions is the third embodiment which is herein claimed in CLAIMS and describes a method and apparatus comprising an illumination system which produces a light pattern ahead of the turbine blades which disrupts a bird's flight pattern and thus reduces and/or prevents blade impact. This third and the Preferred Embodiment comprises:
Further, for the third embodiment, if the light sub-assemblies 300 are mounted in a staggered and uniformly spaced fashion along 305 (i.e., along the axial direction), one placement for each blade, fixed in place, and rotated with the blades, then a screw-like visual projection will result ahead of the wind turbine. Although certainly not required, use of uniformly spaced light sub-assemblies 300 in the axial direction results in a variable “thread pitch” for the projected screw, adding visual confusion. Further, this refinement demonstrates that by allowing movement in the axial direction of one or more light sub-assemblies 300, coupled with appropriate timing of said movement, that essentially any three-dimensional image could be created which would visually appear to rotate, or not rotate, about 335. Such images could include a predator bird with moving winds; such an image could be accompanied by hunting sounds of a predator if more efficient at frightening birds away from the wind turbine.
