Abstract: A counter-rotating fluid-propelling apparatus uses an oblong drive mechanism being oriented substantially orthogonal to the axes of rotation of a pair of counter-rotating impellers and which temporarily and simultaneously engages the edges of the impellers while they are in substantial contact. Each impellers can include a number of substantially rectangular planar panels, hingedly connected to one another along common edges to vertices. Each impeller has an axis of rotation that passes lengthwise through the middle of the impeller such that the axis is parallel to and equidistant from the panel edges. The impellers counter-rotate and remain in constant contact with respect to one another. During each revolution of the impellers, each of the panels of one impeller contacts its counterpart on the other impeller so that planar panels meet flat surface to flat surface and vertex to vertex. The impellers collapse so that constant contact is maintained.

Abstract: A fan assembly includes a first fan and a second fan mounted on the first fan. The first and second fans respectively include first and second frames. The first frame includes four pairs of first flakes on a top thereof. The first flakes of each pair are arranged face to face, and each protrudes a first hook towards the other one. The second frame includes four pairs of second flakes on a bottom thereof. The second flakes of each pair are arranged back to back, and each protrudes a second hook pointing away from the other one. The pair of second flakes are received between a corresponding pair of first flakes with the second hooks respectively engaging with the first hooks.

Abstract: A rotorcraft, such a helicopter or a tiltrotor aircraft, includes a light emitting device configured to provide light at a tip of a rotor blade. The light emitting device includes a light emitting diode arranged on the rotor blade, and a power source, wherein the power source is configured to power the light emitting diode due to a movement of the rotor blade. The power source may include a piezo-electric material configured to create a voltage due to movements of the rotor blade or an electrical generator including a stationary magnet assembly and a moveable coil assembly arranged on a shaft that rotates the rotor blade.

Abstract: A system for adjusting the pitch of a counter-rotating propeller has a propeller shaft, a forward propeller driven by the propeller shaft, and an aft propeller connected with the forward propeller. The forward propeller has a hub, blades mounted within the hub, and an actuator connected with an end of the blades. The aft propeller has a hub, blades mounted within the hub, and a cam assembly connected with an end of the blades. The actuator of the forward propeller has a forward end and an aft end, wherein the aft end is connected with the cam assembly of the aft propeller. Thus, when the actuator moves in an axial direction, the cam assembly moves relative to the actuator and the pitch of the forward propeller blades and the pitch of the aft propeller blades are simultaneously adjusted.

Abstract: A wind harnessing system comprises a substantially grooved shell disposed about a rigid frame. The grooved shell can be constructed of lightweight shell panels connected to one another and to the frame. Alternatively, the grooved shell can be constructed of inflatable shell sections.

Abstract: A vertically sectioned cylindrical accelerator for mounting pairs of wind turbines respectively on opposite sides thereof has a covering of twin-sheet thermoformed plastic panels which are smooth on the outside but carry a multiplicity of small cone-shaped projections on their interior surface. The panels are mounted on a structural member by a single central bolt for free expansion and contraction with variation in ambient temperature. The panels are manufactured in a twin-sheet thermoforming operation wherein one sheet is maintained with a smooth surface and the second sheet is provided with the cone-shaped projections, the two sheets being fused together to form an integral panel of lightweight and high strength characteristics.

Abstract: The wind turbine 20 has sail wings 92 that catch the wind and rotate the turbine wheel 22. The sail wings may be twisted about their longitudinal axis 94 to form pitch and twist in the said wings. A generator is movably positioned in an arc of movement of the turbine wheel and adjusts to the lateral movement of the turbine wheel. Air and liquid cooling is provided to the coils of the rotor and stator of the generator.

Abstract: Arrangements of turbines are described. The turbines are staggered or aligned in the downwind direction.

Abstract: One or more vertical axis wind turbines (VAWT), preferably of the Savonius type, are mounted in a relatively simple and inexpensive manner. For a single VAWT a center pole may be disposed within a hollow shaft of the VAWT with at least upper and lower bearings acting between the shaft and center pole. Alternatively, a short tower or platform may mount a lower bearing (e. g. about 4-14 feet off the ground) for the VAWT shaft, and an upper bearing for the shaft may be mounted by an outrigger. The outrigger is connected at a number of different points (e. g. different arms) by strands (such as steel cables) to stationary supports. Where multiple VAWTs are provided, them may be in a cluster. Each VAWT in the cluster has a structural support in common with at least one other VAWT of the cluster, and each VAWT is operatively connected to a separate useful driven mechanism (such as an electricity or fuel gas generator).

Abstract: A helical auger turbine and hydrokinetic device for use with electrical generators for producing electricity. The auger turbine includes a generally helical turbine blade rotatably mounted on a central shaft, which may be tapered at each end, and a flange extending perpendicularly to an edge of the turbine blade. At least one turbine blade support connection is included for connecting the central shaft to a support structure. An electrical generator may be powered by the helical auger turbine, that can be used in a tidal water flow. The helical auger turbine can operate a high pressure pump connected to a hydraulic accumulator for storing pressurized hydraulic fluid from the high pressure pump. An electrical generator can be operated by hydraulic fluid delivered from the hydraulic accumulator at times of slow water flow. A plurality of helical auger turbines can be horizontally oriented under water, tethered to legs of an ocean platform such as an oil rig secured to the seabed.

Abstract: A device for adjusting an angle-of-attack (?) of blades in a lift-type vertical axis turbine comprising a vertical rotating axis, a rotatable cantilever support wing fixed on the vertical rotating axis, a wind rotor comprising a plurality of blades mounted on the cantilever support wing, at least one cam disposed along an axial direction of the vertical rotating axis, the axial direction of the cam being parallel to the rotating axis, and for any point in a contour line of the cam, the angle of attack ? being set according to the following formula: ?=???, wherein ? is the angle of attack; ? is an azimuth angle; ? is a rotating angle for blades; and ?, ?, and ? are preset values.

Abstract: A counter-rotating fluid-propelling apparatus (800) comprises at least two identical interlocking counter-rotating bodies (801, 802) having a number of rectangular flat panels (811-814), each panel having planar surfaces, and each body having an axis of rotation that passes lengthwise through the middle of the body such that the axis is parallel to and equidistant from the longer edges of the panels. The operation of the apparatus begins with the bodies having a panel from each body abutting against each other. The bodies then counter-rotate with respect to each other driven by a motor (860), such that the panels separate while the vertices between panels remain in contact. This counter-rotating operation causes a displacement of ambient fluid residing beneath the apparatus in a downward motion due to the coming together of panels, and displacement of ambient fluid above the apparatus downward into a vacuum formed due to the separation of panels.

Abstract: In embodiments of the present invention improved capabilities are described for the efficiency with which fluid energy is converted into another form of energy, such as electrical energy, where an array of fluid energy conversion modules is contained in a scalable modular networked superstructure. In certain preferred embodiments, a plurality of turbines, such as for instance wind turbines, may be disposed in an array, where the plurality of arrays may be disposed in a suitable arrangement in proximity to each other and provided with geometry suitable for tight packing in an array with other parameters optimized to extract energy from the fluid flow. In addition, the turbines may be a more effective adaptation of a turbine, or an array of turbines, to varying conditions, including fluid conditions that may differ among different turbines in an array, or among different turbines in a set of arrays.

Abstract: A wind turbine for generating energy includes a first rotor having a first set of blades and a first shaft, and a second rotor having a second set of blades and a second shaft, wherein the first rotor is configured to rotate in a first direction, and the second rotor is configured to rotate in a second direction that is opposite to the first direction. A wind turbine for generating energy includes a first rotor having a first set of blades and a first shaft, and a second rotor having a second set of blades and a second shaft, wherein one of the first set of blades is oriented to receive wind for turning the first rotor, and wherein one of the second set of blades is oriented an at angle to receive wind that is deflected from one of the first set of blades for turning the second rotor.

Abstract: A drive device (D) for driving first and second lift rotors (2, 3) of a twin-rotor rotorcraft, includes link elements provided with first and second transmission shafts (5, 6) for synchronizing the first and second transmission members (74, 84) of first and second main gearboxes (7, 8), the first main gearbox (7) being provided with first power combiner element (73) firstly meshing with the first transmission member (74) and secondly mechanically linked with the first transmission shaft (5) and with the second transmission shaft (6), and the second main gearbox (8) being provided with second power combiner element (83) firstly meshing with the second transmission member (84), and secondly mechanically linked with the first transmission shaft (5) and with the second transmission shaft (6).

Abstract: A system and method for orienting first and second reaction turbines relative to an axis of rotation responds to a fluid flow having a flow orientation axis. The fluid flow is received in a casement. The casement has first and second endplates situated parallel and spaced apart along the axis of rotation. A first half of the fluid flow drives the first reaction turbine to rotate with a first spin orientation in a plane perpendicular to the axis of rotation to produce a first torque about the axis of rotation. The second half of the fluid flow drives the second reaction turbine, offset from the casement plane relative to the first reaction turbine, with a second spin orientation opposite the first spin orientation to produce a second torque about the axis of rotation. The casement is oriented about the axis of rotation in response to the first and second torques.

Abstract: The Wind Mill Tower is a new concept of catching the wind force with more efficiency using the wind force at different levels the Wind Mill Tower consist in the superimposition of several nucleus connected by a main shaft to form a Tower of the vertical Wind Mill, because the atmosphere is compose of various layers of wind, as higher as more strong wind you get, that is the reason of multi modules. Each unit rotate as its own by two ratchets, one on top and one in the bottom also a friction ball bearing underneath each unit to eliminate a friction between them. If the wind dies or is less powerful in certain level, that particular section of the tower idles because the ratchet, it will not make any resistance to the shaft, while the others keep pushing in a rotation motion the shaft generating constant power.

Abstract: A banded turbine configuration has an integral outer band support structure capable of providing two point simple support for a multiplicity of blades. A large scale vertical array has a set of twelve 23 m-diameter banded turbines with up to nine blades and resting on an Open Web Steel Joist (OWSJ) platform. The banded turbine configuration is supported off of a main shaft hub assembly, which is supported by forward and aft pillow block bearing assemblies. The banded turbine allows for a protective screen for bird- and bat-kill prevention. Each banded turbine employs DC alternators to provide a switchable output which is subsequently fed to a dedicated set of high efficiency grid-compatible solid state invertors or, alternatively, to energy storage.

Abstract: A wind turbine arrangement is disclosed that includes a substantially vertical tower mounted to a ground surface, a horizontally-extending hub rotatably fixed in a substantially horizontal plane to an upper end of the tower, at least one radial support arm rotatably fixed with a distal end of the hub, each support arm including a turbine mounting means at a distal end thereof, and at least one electricity-generating turbine selectively mountable with the turbine mounting means of the any of the support arms. An elevator means adapted to raise and lower each of the turbines between an upper loading position adjacent to a lower loading position of each support arm, and a lower loading position adjacent to the ground surface. In use, each support arm may be rotated to the loading position for receiving one of the turbines thereon. The support arm is then rotated about the hub into an operating position.

Abstract: A low pressure turbine for a gas turbine engine includes inner and outer counter-rotating rotor sets, with both said rotor sets driving a common shaft.

Abstract: A vertical axis wind turbine (10) comprises two turbine rotors (12) and (13) with a plurality of curved blades (14) and (15) and coupled together by gears underneath their shafts and rotating synchronously in opposite directions, a multi-function center enhance (16) with three sections namely, the front deflector (21), the upwind blade cavity (22) and the turbulence reducer (23) and together with the two side deflectors (17) and (18) contribute to the efficient flow of the wind stream to the downwind moving blades (28) and (29) of the two turbine rotors. The center enhance separates the two turbine rotors on opposite sides. The wind turbine (10) has a cylindrical housing structure (11) with two levels of horizontal platform (19) and (20) housing various components of the machine, and a yaw drive mechanism that orients properly the machine into the wind.

Abstract: A fan array fan section in an air-handling system includes a plurality of fan units arranged in a fan array and positioned within an air-handling compartment. One preferred embodiment may include an array controller programmed to operate the plurality of fan units at peak efficiency. The plurality of fan units may be arranged in a true array configuration, a spaced pattern array configuration, a checker board array configuration, rows slightly offset array configuration, columns slightly offset array configuration, or a staggered array configuration.

Abstract: A linear wind powered electric generator (LWPEG), which is particularly adapted for installation at geographical sites subject to lower wind intensities. More specifically, there are provided design concepts for an LWPEG, possessing reasonable economic parameters for utilization at the lower-intensity wind sites. Moreover, the linear wind powered electric generator is based on a track based wind power generator, incorporating aerodynamic designs, which are adapted to reduce mechanical complexities presently encountered in this technology, while being cost-effective both in construction and in connection with the operation thereof.

Abstract: Improvements to wind farms and wind generators for harnessing wind energy or generating electricity from wind. Secondary wind turbines are provided at particular locations within a wind farm to generate additional electricity, in some embodiments, using a common electrical power collection system. Enclosures or venturis may surround wind turbines to facilitate mounting close to the ground. Venturis may accelerate wind speed through the turbine and may have a particular shape, may be made of particular materials arranged in particular ways, or both. In different embodiments, wind turbines may be axial-flow horizontal-axis turbines, or may be Savonius turbines, as examples. And in some embodiments, wind turbines may be combined with other power production equipment, such as solar power equipment, for instance.

Abstract: A modular multi-turbine unit of fixed toroidal support structures having a rail system designed to allow each of the plurality of turbines to rotate to a most efficient position relative to the wind for generating power, a computer control system capable of positioning each of the plurality of turbines to most effectively generate power from the wind, preventing damage to the turbines, and providing a wind predictive model based on the wind characteristics for the area in which the wind turbine is located.

Abstract: A power generating turbine is disclosed having a vertical axis, a generator connected to the vertical axis, and coupled blades connected to the vertical axis. The coupled blades are a horizontal axis; one or more blades, comprising a first set of blades, attached near one end of the horizontal axis; and one or more blades, comprising a second set of blades, attached near the opposing end of the horizontal axis wherein the broad sides of the second set of blades are orthogonal to the broad sides of the first set of blades, the broad sides of the blades are parallel to the horizontal axis, and the blades pivot on a vertical path. The middle portion of the horizontal axis is pivotably connected to the vertical axis. Solar cells can be attached to various parts of a turbine for generating power.

Abstract: A system for arranging and operating an array of wind machines to protect crops from damaging weather conditions, such as freezing frost, rain and heat. The method includes a wind machine positioned to force air across the crop. The wind machine is preferably a propeller/tower configuration. The operational method of the wind machine array includes the steps of sensing ambient meteorological and the hardiness of the crop to withstand a particular adverse weather condition and operating the wind machines in response to these factors. Multiples of wind machines are employed in the preferred embodiment of the method, the siting of the wind machines preferably based upon topographic and historical meteorological conditions. The operation of the wind machines can be automatically and remotely operated with the aid of satellite communications including internet links.

Abstract: A blower includes two contrarotating axial fans located to be rotated reversely with each other in accordance with rotations of its rotation shafts arranged on an axial line. In the blower, a rotation drive shaft of a motor is coupled to the rotation shafts of the axial fans through a gear portion, and the gear portion is housed in a gear box. Each of the axial fans includes a boss portion having a recess shape opened in an axial direction of the axial fan, and a plurality of blades located radial outside of the boss portion. Furthermore, the axial fans are located such that the recess shapes of the boss portions are opposite to each other, and the gear box is located between the boss portions of the axial fans, and is covered by the boss portions from two sides in an air flow direction of the axial fans.

Abstract: A floating power generation assembly comprises at least three floating units (900) floating on a body of water, and at least three anchors (916) secured to a solid surface beneath the body of water, each of the floating units (900) being provided with a power generator, the floating units (900) being arranged substantially at the vertices of at least one equilateral triangle. Ship borne apparatus for deploying the floating units of such a power generation assembly and a novel multiple wind turbine assembly are also described.

Abstract: A rotor system (12) for a helicopter (10) includes a rotating shaft (82). A gimbaled hub assembly (56) is coupled to the rotating shaft (82). Rotating blades (24) and non-rotating blades (33) are coupled to the gimbaled hub assembly (56). The non-rotating blades (33) provide lift for the helicopter (10) in forward flight unloading the rotating blades. The rotating and non-rotating blades (24, 33) provide equal and opposite rolling moments for lift offset operation.

Abstract: A wind power plant includes four main elements: a foundation (29), at least one supporting structure (21), a carrying construction (23) having a vertical axis (25) and being rotatable around the vertical axis, and at least one rotor (45), (49), (52) positioned on the carrying construction. The rotors can have horizontal, vertical, and inclined axes of rotation in different combinations. Each rotor has at least two blades (53) arranged along its axis of rotation. Since the rotors used in the invention have a small diameter, the wind power plant can produce energy under high and low wind speeds, consequently producing more energy per year than known wind turbines. Also, because the rotors have rectilinear blades for their manufacture expensive composite materials and complicated expensive equipment are not required. For these reasons the wind power plant of this invention will produce energy at lower cost.

Abstract: A fan array fan section in an air-handling system includes a plurality of fan units arranged in a fan array and positioned within an air-handling compartment. One preferred embodiment may include an array controller programmed to operate the plurality of fan units at peak efficiency. The plurality of fan units may be arranged in a true array configuration, a spaced pattern array configuration, a checker board array configuration, rows slightly offset array configuration, columns slightly offset array configuration, or a staggered array configuration.

Abstract: A windmill 10 includes a frame 11 and a rotor 12 provided rotatively around the vertical shaft center. The rotor includes bosses 23, 24 located above and below, plural transversal blades 25 extending radially from the bosses, longitudinal blades 26 held by the front edges of the transversal blades 25 of both above and below bosses. The frame includes bearing 19, 20 supporting the bosses 23, 24 of the rotor rotatively around the vertical shaft center, spokes 17 provided radially supporting the bearing, and legs 15 holding the spoke 17 away from the ground. In the lower bearing 20, a generator connected to the boss 24 of the rotor 12 is accommodated.

Abstract: A fan array fan section in an air-handling system includes a plurality of fan units arranged in a fan array and positioned within an air-handling compartment. One preferred embodiment may include an array controller programmed to operate the plurality of fan units at peak efficiency. The plurality of fan units may be arranged in a true array configuration, a spaced pattern array configuration, a checker board array configuration, rows slightly offset array configuration, columns slightly offset array configuration, or a staggered array configuration.

Abstract: A sky turbine, having impeller blades with a plurality of panels that can telescope inward and outward. The pitch of the panels can be adjusted, and the pitch of each panel on a blade, passing from the innermost panel to the outermost panel, differs from the pitch of the previous panel by a certain adjustable amount. The sky turbine is preferably mounted above a city at a sufficiently high elevation that air current will be generally faster than just above the ground. In the preferred embodiments, a wing with two pods is pivotally mounted on a tower. Each pod has front and rear shafts, from which four blades extend. Servomotors cause the wing to turn so that its center of symmetry is parallel to the direction the sky is moving, cause the pitch of the panels of the blades to change, and cause the panels of the blades to telescope.

Abstract: A propulsion linearizing mechanism is provided for linearizing a fluid flow. The mechanism includes a frame having a cylindrical outer baffle which rotatably supports a plurality of propeller elements thereon. Each propeller element defines a respective sweep area as the propeller element is rotated which overlaps sweep areas of adjacent propeller elements. The outer baffle circumscribes an outer periphery of the collective sweep areas of the respective propeller elements. The propeller elements rotate in the same direction whereby forces of curvature flow of adjacent propeller elements substantially cancel one another to linearize fluid flow through the mechanism. Additional baffles and infills within the areas of non blade sweep may be provided for particular applications of the mechanism.

Abstract: An automotive engine-cooling fan assembly uses pairs of overlapping fans to improve flow uniformity through the heat exchanger cores and to maximize the amount of fan power that can be achieved with limited motor sizes. One fan of each pair has upstream supports and the other has downstream supports, and these supports are so configured to minimize the axial dimension of the assembly. The use of banded fans maximizes fan performance, and blade skew minimizes fan noise.

Abstract: A propeller-turbine engine includes a gas generator engine with a gearbox and a propeller hub, wherein two propellers are arranged axially offset relative to each other on the propeller hub which rotate in the same direction.

Abstract: A wind turbine with an array of rotors arranged at various heights. Each rotor is optimized for the height at which it is located. Optimization of each rotor could include selection of rated power, solidity, tip speed, blade twist, blade taper, or rotor diameter. Each rotor can also be operated in a manner that is optimized for the wind speed it experiences. Optimized operation parameters could include blade pitch angle or rotor speed.

Abstract: A high torque accumulator wind machine comprising a rotor means that comprise a plurality of blade assemblies that have ratchet bearings, an electric generator and a tower means that expose a plurality of blade assemblies to the wind to capture large amounts of wind enrgy in low wind velocity areas as well as in high wind velocity areas wherein the torque elements produced by the blade assemblies are delivered by the torque transporter means to the high torque accumulator shaft that combines the delivered torque elements into a single big force for rotating said electric generator thereby enabling said high torque accumulator wind machine to produce more electricity than conventional means at lower expenses.

Abstract: A flowing water actuatable turbine system, wherein the turbine system is mounted for operational co-operation with water current by means of an upstanding column/pile in such manner as to be axially displaceable length ways of the column/pile. The turbine system is preferably arranged to be rotatably about the longitudinal axis of the column. Floatation means can be provided for operationally supporting the turbines which can include blade pitch control.

Abstract: A wind energy conversion apparatus comprising a supporting structure including a number of spokes, which is rotatably journalled on a horizontal main shaft, wherein auxilliary rotors having an at least substantially circular plane of inflow are mounted on the ends of the spokes, wherein each of the auxilliary rotors has a plane of inflow which includes an acute angle with the central axis of the main shaft and which intersects the central axis upstream of the main shaft, and wherein the auxilliary rotors are made up of rotors including rotor blades or of conical bodies having a large apex angle, whose base is directed towards the oncoming wind.

Abstract: A wind turbine with an array of rotors arranged at various heights. Each rotor is optimized for the height at which it is located. Optimization of each rotor could include selection of rated power, solidity, tip speed, blade twist, blade taper, or rotor diameter. Each rotor can also be operated in a manner that is optimized for the wind speed it experiences. Optimized operation parameters could include blade pitch angle or rotor speed.

Abstract: An axial flow hair dryer comprises a generally circular main housing with a transitional portion that smoothly reduces the housing diameter to an outlet. A first fan stage in the main housing generates an axial air flow through the housing. An outer duct has two axial extensions secured to the housing near the beginning of the transitional portion, and the housing air outlet introduces air exiting the housing into the outer duct. The housing and the outer duct form two additional ambient air intakes extending between the axial extensions in a smooth arc toward the main housing outlet. A second fan stage includes a second axial flow impeller in the outer duct for generating air flow through the ambient air intake. The second axial flow impeller includes inner and outer blades separated by an annular shroud that forms an extension of the main housing flow passage. A guide duct in the outer duct forms a further extension of the extended air flow passage, and the guide duct includes stator vanes at its outlet.

Abstract: Improved wind-engine, comprising a frame (1) and several wind devices (2) mounted on different stages, one above the other on transversal parts (4) of this frame (1) with at least one separation wall (5, 6) mounted on the frame (1), between the wind devices (2) situated one above the other.

Abstract: An electric fan including a hood having a plurality of tubular members in each of which there is a cylindrical member, a plurality of bell-shaped members each mounted on each of said tubular members, and a plurality of protecting covers each mounted on an outlet of each of said tubular members, and a base portion mounted under said hood and having a motor provided with an output gear engaged with a plurality of fan gears each fixedly mounted on an axle extending from said base portion upwardly into said cylindrical member, and a plurality of impellers each mounted on the top end of said axle, whereby the electric fan can make air currents in a range of 360 degrees.

Abstract: A refrigeration system where the refrigerant starts out as a liquid at ambient temperatures and pressures and is expanded to a very low pressure and temperature through the use of a special design ejector and pump assembly. The preferred design uses a new type of centrifugal pump which is designed to produce a high velocity discharge rather than pressure. The refrigerant in expanding to a gas extracts BTU's from its surroundings.

Abstract: In a preferred embodiment, a tail rotor assembly for a helicopter, which includes: a first rotor disposed on a first side of the distal end of a tail boom of the helicopter and rotatable in a first geometric plane; and a second rotor disposed on a second side of the distal end of the tail boom, the second rotor being rotatable in a second geometric plane.

Abstract: A self-contained fan turret unit for use with a tower air recirculating system includes a housing positionable for attachment to the tower system. The housing includes an extendable column assembly bearing a turret assembly to which are attached one or more fans, inlet bells and discharge cones with the turret assembly being movable from a position within the housing to one above the housing by the column assembly. The turret is supported by an air spring isolator and, when extended, is connected to the housing and the tower unit by flex joint isolators. A cowling is also provided for releasable attachment to the turret. The turret is rotatable and extendable arms are provided to interconnect the column assembly and the fans for selective removal thereof from the turret.

Abstract: A windmill installation (10) includes a windmill (12) supported on a tower (18) that includes three legs (20, 22, and 24). The connections of the legs (20, 22, and 24) to their respective bases (36, 37, and 38) are provided by compliance members (30, 32, and 34) that are compliant enough that the natural frequency of axial bending of the windmill installation is less than the frequency with which blades (14) of the windmill (12) pass behind the tower (18). Also, a windmill compliance assembly (28) provides the connection between the windmill (12) and the tower (18) and has enough compliance that the natural frequency of pivotal bending is also below that frequency. As a result, vibration at a resonant frequency of the structure is avoided during normal operation.