WO2013003737A2

WO2013003737A2 - Sun tracking solar power collection system designed for pole structures including wind turbine poles

Info

Publication number: WO2013003737A2
Application number: PCT/US2012/044960
Authority: WO
Inventors: Robert D. Lundahl; Robert W. Cutlip
Original assignee: Advanced Technology & Research Corp.
Priority date: 2011-06-29
Filing date: 2012-06-29
Publication date: 2013-01-03
Also published as: US20130000632A1; WO2013003737A3

Abstract

A unique design for a sun tracking, solar panel mounting system can be mounted onto utility light poles, wind turbine poles, and other pole-type structures. Rings are clamped around the pole and form a structural interface to support the tracking mount assembly and allow it to rotate around the centerline of the pole. An actuator powers rotation of the tracking structure to the right or left around the centerline of the pole. A secondary structure in the mount assembly supports solar panels on either side of the vertical mounting pole and an optional second actuator tilts the solar panels up and down in elevation. A control system reads the position of each actuator and periodically adjusts them to track the motion of the sun and optimize solar energy collection efficiency.

Description

SUN TRACKING SOLAR POWER COLLECTION SYSTEM DESIGNED FOR POLE STRUCTURES INCLUDING WIND TURBINE POLES

BACKGROUND

Field of the Invention:

This invention relates to solar energy electrical power collection systems, and specifically to the design of a solar panel mounting system that is mounted on pole structures and tracks the movement of the sun with a single or dual axis motion and programmable control. Brief Description of Prior Art

Pole mounting systems are prevalent in prior art. However, most are for static mounting. Patent # 4,265,422 shows a widely used approach for statically mounting a solar panel onto pole-type structures to power local electronic systems. The mounting technique uses "U" bolts to encircle the pole and attach the solar panel mounting structure. This mounting technique is easy to use on existing poles since it is not necessary to modify or drill into the structure of the pole and it is also not necessary to put it over the top of the pole, where there could be a variety of existing power cables or other appendages. This type of mounting system is static and does not move the solar panel to track the sun. The power generated by a non-tracking panel is 30 to 40% less than what can be gained from a sun tracking panel. Most of these applications are designed simply to power a local electronic system and the loss of efficiency is addressed by over-sizing the panels for the local requirement. This is not an effective approach for generating excess electrical power to be fed back into the electrical grid.

Tracking pole mounted systems are also found in prior art. However, these systems are designed to be mounted on top of a pole structure. Patent # 1,1 1 1,1 1 1 shows a common top-mounted tracking system and these are available in both single axis and dual axis tracking configurations.

These mounting systems incorporate the sun tracking function and generate more power than the non-tracking panels. However, the mechanical system providing the 2-axis motion must be mounted on top of the pole structure. This approach does not lend itself for retrofitting onto existing utility poles and it would also be impossible to use on a wind turbine pole where the top of the pole is occupied by the turbine itself. This design limits the potential installation sites.

These top mounted configurations cannot be easily mounted to the midsection of the pole where there is adequate area and access. The structure and drive mechanism of these top-mounted pole systems are not designed to encircle the pole. It would be difficult or impossible to slip the mechanism over the top of the pole and slide it down into a middle position.

These types of mounting systems can only be installed on the tops of the poles and this is not a convenient location for installation or maintenance and it would be impossible to use such a mounting system on a pole that is supporting a wind turbine.

SUMMARY

It is to be understood that both the following summary and the detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. Neither the summary nor the description that follows is intended to define or limit the scope of the invention to the particular features mentioned in the summary or in the description. Rather, the scope of the invention is defined by the appended claims.

In certain embodiments, the disclosed embodiments may include one or more of the features described herein.

Utility poles for lighting, power, communications, and wind turbines are prevalent in today's landscape. They are existing industrial structures that can be utilized to support solar panels and they also provide convenient access to the local power grid. These are attractive features for solar power collection systems as part of a distributed generation system. Using existing poles for a mounting structure greatly reduces the cost to install the solar panels and no additional real estate is required. Utilizing existing poles also provides an easy access to the electrical grid so that power produced by the solar panels does not need to be stored but can be "sold" back to the grid for others to use.

Utilizing wind turbine poles in particular provides a hybrid energy collection system that utilizes both wind and solar energy and can provide power more often than either source alone.

This invention presents a detailed approach for the design of sun tracking solar panel mounting system that is easily attached to different poles, including light poles, wind turbine support poles, and standard utility poles. This system is unique in its ability to be mounted at an intermediate position on the pole and it can be retrofitted onto a wide variety of existing poles. The design of this tracking system allows it to share a pole with a wind turbine, streetlight, or overhead wiring.

Powered actuator(s) and a control system may be integrated within the mount structure to actively rotate the solar panels around the vertical axis of the pole to track the sun and maximize daily power production. A simple single-axis tracking system may be configured where the solar panels are held at a fixed inclination and the entire array is rotated around the vertical axis of the pole to track the sun in azimuth. An even more efficient dual-axis tracking system may be configured, where the inclination of the solar array is also changed during the day, to track the sun in azimuth and elevation.

One application for this invention is to configure highly efficient power generation systems on existing light poles, wind turbine poles, utility poles, and other common outdoor pole structures. However, it should be obvious to one skilled in the art that this tracking mount system could be used on any pole-type structure, as well as utilized for a variety of other tracking or pointing applications of other antennas, cameras, etc.

A new sun tracking mount module for a solar power generation system is designed to be mounted on vertical poles. Two rings are installed on a pole and support upper and lower bearing races for the powered tracking module. The bearing races themselves may be incorporated into the rings or they may be separate sections and attached to the rings which are affixed to the pole. The tracking module incorporates another bearing surface or rollers to interface with the bearing races of the rings and allow the tracking module to smoothly rotate around the center line of the pole. The tracking module may be constructed in two halves, so that the module can opened up, positioned around the pole, and then closed to capture the rings around the pole. The bearing surfaces or rollers in the tracking module match the bearing races attached to the pole, providing a smooth rotational interface between the tracking module and the pole structure. The diameter of the bearing races around the pole can be designed to be tight to the pole diameter or larger than the pole diameter, to provide additional space inside between the tracking module (other than the rings) and the pole itself. The tracking module incorporates a horizontal structure to support an array of solar panel(s) on either side of the pole.

In various embodiments, the rings may be considered part of the sun tracking mount module or separate from it, and may be removably attachable to the remainder of the mount module or integral with it. If removable therefrom, the rings can be used to interface with and secure to a pole or other central structure a variety of different types of mounts. Even if the bearing races are not integral with the rings, the rings and bearing races together may be referred to as split ring bearings.

The basic tracking module may be configured as a 1-axis tracking system or a 2-axis tracking system.

For single-axis tracking, a primary first-axis drive motor is positioned on the tracking module and connected by a drive chain to a sprocket that is fixed around the pole. When this motor is activated it rotates the entire tracking module around the center-line of the mounting pole, providing a single rotational axis. This is called single-axis motion, and it is used to rotate the solar array and track the sun's position in Azimuth only. For single-axis configurations, the inclination of the solar panels is fixed.

For two-axis tracking, a second drive motor is added to actively change the inclination of the solar panels. This motion, combined with the rotational movement of the tracker module, allows the complete tracking of the sun in azimuth and in elevation for the maximum power generation efficiency.

The solar panels may be positioned on either side of the support pole, providing them unrestricted freedom of motion to rotate around the pole and change elevation to perfectly track the sun's position. The shadow from the pole is always between the panels and will not degrade their performance.

The tracking module may support the solar panels in a balanced position to minimize any moment loads to the mounting pole structure. Panels are positioned on either side of the pole as a balanced load. The panels themselves are connected to the horizontal cross arm structure, close to their center of gravity, so they maintain a balanced configuration as they change their pointing elevation as they track the path of the sun.

The solar panels may generate DC voltage. A small amount of power is used by the positioning motor(s) and some energy is stored for end-of-day repositioning. The majority of the energy produced may be converted to AC power and fed back to the utility electrical grid with a "grid tied" inverter. A grid tied inverter matches the frequency of the generated AC power with the frequency of the local electrical grid, so that excess power can be fed directly to the local power grid for credit or outright sale as independently produced power.

A new tracking mount device includes one or more split clamping rings having central openings, each having two or more bearing sections, fastening structures configured to secure the split clamping rings to a central object, and a tracking mount configured to rotatably mate with the split clamping ring bearing sections to secure the tracking mount to the central object without being installed over either end of the central object. If the bearing sections are not integral with the clamping rings, they may need to be secured to one another separately from the clamping rings being secured to the central object. The tracking mount is configured to rotate around the central object on the split clamping ring bearing sections. A solar panel mounting structure may be attached to the tracking mount and configured to attach to one or more solar panels. A linear actuator may be configured to rotate the solar panel mounting structure about an axis perpendicular to the major axis of the central object.

A motor may be configured to rotate the tracking mount around the central object on the split clamping ring bearing sections. A control system may be configured to control rotation of the tracking mount around the central object. Each split clamping ring's bearing sections may include one or more bearing surfaces and the tracking mount may include rollers configured to rotatably mate with the bearing surfaces. One or more inserts may be configured to be secured to one or more of the split clamping rings in the central openings to reduce the effective internal diameter or change the shape of the central openings to accommodate smaller diameter or differently- shaped central objects. The control system may be configured to periodically update the position of solar panels attached to the tracking mount to track the sun by rotating the tracking mount around the central object. The control system may be configured to periodically update the position of solar panels attached to the tracking mount to track the sun by rotating the solar panels about an axis perpendicular to the major axis of the central object. A new solar energy collection system includes a tracking mount device and one or more solar panels attached to the tracking mount. The solar panels may be positioned such that they are not between the pole and the sun. A control system may be configured to detect unsafe forces on the solar panels based on sensor inputs and rotate the solar panels into a stow position. Batteries may be configured to store excess electrical power. A grid tie inverter may be configured to convert excess electrical power to AC power and feed it back into an electrical grid.

A control system may be configured to provide excess electrical power to an energy storage device. The solar panels may be mounted at a fixed elevation angle. The solar panels may be configured to pivot to relieve excessive wind load forces. A surface of the solar panels or a support frame may include graphics for promotional purposes. The pole may be a vertical support pole for a wind power turbine. The solar panels may be mounted on a support structure in an offset pattern, providing gaps between solar panel sections to reduce wind loading.

In a solar energy collection method, a split clamping ring is placed around a central object, the split clamping ring is clamped to the central object to form a split ring bearing around the central object, and a tracking mount is rotatably mated with the split ring bearing and the tracking mount is secured to the central object without installing the tracking mount over either end of the central object.

These and further and other objects and features of the invention are apparent in the disclosure, which includes the above and ongoing written specification, with the drawings.

OBJECTS OF THE INVENTION

This application presents a design for a sun tracking solar panel mount designed to be easily installed on a variety of pole structures used for street lighting, wind turbines, and power

transmission, signage, and other supports.

A further object of this design is to provide a mounting system that can easily accommodate differently sized and shaped poles.

A further object of this design is to provide a mounting system that can easily be retrofitted onto existing poles.

A further object of this design is to provide a mounting system that can be used specifically for wind turbine poles where access to the top of the poles for installation is not possible.

A further object of this design is to provide a means for a cost-effective solar installation. A further object of this design is to provide an installation location for solar panels that is easily accessible to an existing electrical grid.

A further object of this design is to provide an installation location for solar panels that is easily accessible by service personnel and equipment.

A further object of this design is to provide a pointing control system that is based on microprocessor control.

A further object of this design is to provide an automated method to coordinate the movement of the device to correctly track the sun from any geographical location.

A further object of this design is to provide a means to reduce wind load from installed PV panels.

BRIEF DESCRIPTION OF DRA WINGS

The accompanying drawings, which are incorporated herein and form a part of the specification, illustrate exemplary embodiments and, together with the description, further serve to enable a person skilled in the pertinent art to make and use these embodiments and others that will be apparent to those skilled in the art. The invention will be more particularly described in conjunction with the following drawings:

Figure (1) Pole mounted sun tracking solar panel mount- This illustration shows an overview of a sun tracking mount, in an embodiment, installed on a light pole.

Figure (2) Split bearing interface with the mounting pole - This illustration shows split bearing clamps used to attach a tracking mount to a mounting pole.

Figure (3) Clamping ring inserts - This illustration shows clamping ring inserts

Figure (4) Alternate bearing race attachment - This illustration shows a mounting pole adapted for mounting bearing races.

Figure (5) Captured tracking mount - This illustration shows a mount structure attached to a mounting pole and capturing a bearing interface.

Figure (6) Tracking mount installed on mounting pole - This illustration shows a tracking mount installed on a mounting pole and how the actuators mechanically provide the axis of motion for the solar panels.

Figure (7) Position control system - This illustration shows one embodiment of a microprocessor-based position controls system for sun tracking.

Figure (8) Utility Grid Interface -This illustration shows one embodiment of how the generated power can be interfaced with a utility grid.

Figure (9) General daily motion profile - This illustration shows a general motion profile for movement of a tracking mount and solar panels.

Figure (10) Fixed mount wind load reduction - This illustration show a method to mount solar panels to reduce wind loading for most wind directions.

Figure (11) Passive compliant wind load reduction - This illustration shows panels mounted with a spring-loaded pivot to allow relief of excessive wind pressure.

Figure (12) Active wind load reduction - This illustration shows how the orientation of the solar panels can be changed to reduce anticipated wind loading from a variety of information sources.

Figure (13) Active wind load reduction - This illustration shows different ways that the surface area of the solar panels can be utilized for advertising graphics.

Figure (14) Tracking mount installed on wind turbine pole - This illustrations shows an overview of a sun tracking mount, in an embodiment, installed on a wind turbine pole to form a hybrid power generation system.

DETAILED DESCRIPTION

A sun tracking solar power collection system designed for pole structures including wind turbine poles will now be disclosed in terms of various exemplary embodiments. This specification discloses one or more embodiments that incorporate features of the invention. The embodiment(s) described, and references in the specification to "one embodiment", "an embodiment", "an example embodiment", etc., indicate that the embodiment(s) described may include a particular feature, structure, or characteristic. Such phrases are not necessarily referring to the same embodiment. When a particular feature, structure, or characteristic is described in connection with an embodiment, persons skilled in the art may effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

In the several figures, like reference numerals may be used for like elements having like functions even in different drawings. The embodiments described, and their detailed construction and elements, are merely provided to assist in a comprehensive understanding of the invention. Thus, it is apparent that the present invention can be carried out in a variety of ways, and does not require any of the specific features described herein. Also, well-known functions or constructions are not described in detail since they would obscure the invention with unnecessary detail.

The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The following sections describe mounting a solar panel tracking system onto light poles and wind turbine support poles. It should be obvious that this simple and robust method can also be utilized for building a sun tracking solar collection system on practically any pole structure, including a single-purpose pole dedicated to the mounting of the solar panel. Similarly this invention could also be applied to a variety of different pointing applications, for example for antennas or other optical systems.

Figure (1) Pole mounted sun tracking solar panel mount - This illustration shows a pole- mounted sun tracking solar panel mount installed on a utility light pole. Using an existing light pole provides a cost-effective approach for mounting a solar power collection system. The abundance of existing lighting fixtures provides immediately available installation sites. Existing utility light polls provide easy access to the local electrical power grid, since they are already connected and currently serviced by service personnel and equipment.

In this illustration, the tracking mount (100) is shown mounted to the mid-section of a conventional light pole (200). Connecting arms (300) on either side of the tracking mount (100) connect to solar panels (400). To track the sun, the tracking mount (100) provides the solar panels (400) with either one or two axis of motion. For East- to- West tracking, the tracking mount (100) itself rotates about the center- line of the light pole (200) in the horizontal plane of rotation (500) for single- axis tracking. To track the sun in elevation above the horizon, the connecting arms (300) of the tracking mount (100) rotate around their center- line and in the vertical plane of rotation (600), providing a second axis of tracking.

Figure (2) Split bearing interface with mounting pole - This illustration shows how a split clamping ring (700) is used to encircle the pole (800) and provide a bearing surface (1000) for a tracking mount to rotate around the pole. The split clamping ring approach allows this mounting interface to be clamped around an existing pole where it may not be practical to access the top of the pole or otherwise attach a mounting structure. In the illustration, the split clamping rings (700) are secured around the pole structure (800) with screws (900) or other fasteners to clamp the sections securely around the mounting pole diameter. Some larger-diameter poles may utilize several separate clamping ring (700) sections to encircle the pole- in other words there may be, for example, three or four ring sections making up each clamping ring, rather than two. An upper and lower bearing surface (1000) may be installed on the pole structure to provide a structural interface for a solar panel structure.

Figure 3 Clamping ring inserts - Clamping rings can be manufactured with a wide variety of bore sizes and inside diameter configurations to match the size and profile of the installation poles and maintain a consistent bearing surface for a tracking mount interface. Figure 3 shows how a separate insert (1010) may be used inside a clamp ring (1020) to accommodate a differently-shaped or sized pole, such as a square pole, and in this way increase the adaptability of the split bearings to an even wider range of utility poles. Figure 4 Alternate bearing race attachment - As an alternate approach to clamping rings, a structure can be attached or incorporated into the pole itself to provide a mounting structure and attachment points for the bearing races. This figure shows an example where a flat ring (1030) is permanently attached to the pole (1040) by welding or other means, providing a mounting structure for the bearing races (1050). This same mounting structure can also be utilized to attach a drive sprocket (1060). In this example, common fasteners (1070) are used to attach both the bearing races and a drive sprocket onto the attached flat ring (1030) structure. Bearing races may also be attached directly to the pole itself, provided threaded mounting points or other attachment means in the pole.

Figure (5) Captured tracking mount - This illustration shows how the front panel (1 100) of a tracking mount (1200) my be removable and installed from the opposite side of the mounting pole (1300). Rollers (1400) or other bearing features mounted on the front panel (1 100) and within the tracking mount (1200) interface with the split bearings (1500) and provide a structural and rotational interface between the tracking mount (1200) and the mounting pole (1300). Many different roller and bearing configurations can be envisioned to provide the structural and rotational interfaces required within the spirit of this invention. Wheels, straight rollers, "V" groove rollers, and low friction plastic bearings etc. used in different quantities, geometries, and orientations are all possible approaches to provide this bearing interface. The front panel (1 100) overlaps the body of the mount (1200) on the sides, and they may be connected at the overlap by any convenient fastening mechanism, such as screws, clips, or rivets. Once the bearings (1500) are secured to the pole, the front panel (1 100) and mount body (1200) may be positioned over the bearings (1500) with rollers (1400) or similar engaged with the bearings (1500) and then secured to each other. Solar panels may then be mounted to a rotating horizontal sleeve (2300) to complete an installation.

Figure (6) Tracking mount installed on pole - This illustration shows the tracking mount as installed on a mounting pole. The tracking mount (1600) encircles and captures the mounting pole (1700). In this embodiment, an array of rollers (1800) mounted inside the front cover (1900) and main body of the tracking mount (1600) interfaces with the bearing surface (2000) of the split bearings (2100,2600). If full two-axis tracking is used, a linear actuator (2200) is installed between the structure of the tracking mount and the rotating horizontal sleeve (2300). Extension or retraction of the linear actuator (2200) will rotate the sleeve member (2300) that supports the solar panels and thereby adjust the pointing elevation of the solar panel. The conventional single-axis tracking is performed by the azimuth drive motor (2400) which is attached to the tracking mount (1600) and powers a belt drive (2500) or other similar drive train connected to the lower split bearing (2600). Activation of the azimuth drive motor (2400) causes the tracking mount (1600) to rotate horizontally about the mounting pole (1700). Many different actuator and drive configurations for the azimuth and elevations drives are possible and anticipated by this invention. Chain drives, direct gear drives, worm drives, and cable drives are other common approaches that would be appropriate for the Azimuth axis. Mechanical ball screws and hydraulic cylinders are popular methods for the push and pull activation required for the elevation axis. The embodiment described here is one approach that is simple and low-cost using off-the-shelf components. A control system (not shown) may be located in any convenient location, inside or outside of the tracking mount (1600) and electrically connected with motor (2400) and/or linear actuator (2200).

Figure (7) Position control system - This illustration shows a position control system for the tracking panel mount with two-axis tracking (azimuth and elevation). Single-axis tracking may be used to save cost and complexity, in which case only the azimuth pointing axis would be controlled. A microprocessor (2700) is used to control the elevation motor (2800) and the azimuth motor (2900) by providing them with DC voltages through elevation relay (3000) and azimuth relay (3100) respectively. Voltages can be reversed to enable bi-directional movement. Both motors incorporate position feedback. The elevation motor encoder (3200) and the azimuth motor encoder (3300) communicate their positions to the microprocessor (2700).

A Global Position System (GPS) (3400) and GPS antenna (3500) determine the Latitude and

Longitude of the current tracking panel mount position and also communicate the current date and time.

Sun tracking is accomplished by the microprocessor (2700) calculating the relative position of the sun and coordinating the positions of both the elevation motor (2800) and the azimuth motor (2900).

The position of the solar panels is updated on a pre-set time interval. The interval is chosen to optimize the overall efficiency that is a function of pointing accuracy and the power required for the frequency of re-positioning.

Many different approaches can be used to accomplish the actual positioning function and they are anticipated by this invention. The preferred embodiment described above presents an automated solution where the sun positions are calculated based on Date, time of day, and the latitude and longitude of the installation location and the solar panels are positioned accordingly to maximize efficiency. However, a much simpler solution may be used where the positions are "pre-programmed" and stored in a look up table for each of the update intervals.

For simplicity, it is assumed that installers would correctly orient the system North and South and these positions would be used for initialization. A more automated approach may be used where an electronic compass is used to determine the North and South orientation of the unit after it is installed, and the internal coordinates of the control system are updated automatically upon initialization.

The Solar panel (3600) generates DC voltage for the Grid Tie inverter (3700) that converts it to AC voltage for delivery back to a utility power grid (3800). A small portion of the power generated is used to trickle charge an on board battery or other power storage device (3900). This battery or power storage device (3900) provides power to operate the azimuth and elevation (if used) drive motors as well as the microprocessor (2700) and the GPS unit (3400) during periods of no sunlight or at the end of the day when the solar panels (3600) are repositioned from the direction of the setting sun to the direction of the rising sun for the following sunrise.

Figure (8) shows how the generated power can be provided to the grid - Providing excess electrical power to the grid for others to use is one purpose of this system. Figure 8 shows one of the basic configurations for delivering electrical power to the grid. Other variations are anticipated and within the scope of this invention, including powering electrical equipment directly, supplying energy to other energy storage devices, and hybrid systems that include energy storage, direct energy usage, and automatic grid-tied and off-grid operations. The tracking solar panel system (4000) is shown attached to a utility light pole (4100) that is connected to a Utility Pole AC Power (4200) line.

Generated solar panel DC power (4300) is delivered to a grid tied inverter (4400) where it is converted to AC power that is in sync with the utility pole AC power (4200).

Many different "Grid Tied" inverters are commercially available and incorporate different features. The basic functionality of an inverter is to convert DC power into AC power. The grid tied inverters are a special configuration that will "sense" the phase of the utility line and match the phase of the converted AC power so that it can be directly connected. As a safety provision grid tied inverters will stop producing AC power if the utility line loses power or frequency.

Synchronous AC power can be provided to the AC power grid through a separate metering system (4500) to log how much power has been provided to the grid for the purposes of reverse billing.

Several commercially available grid tie inverters (4400) also provide data over the utility AC power (4200) for a smart grid interface (4600) component to report on solar panel health, power output and other performance metrics. The smart grid interface (4600) devices can be connected to the internet (4700) to report solar performance metrics into a database that is accessible over the internet for a variety of monitoring and control functions that can be performed remotely over the world wide web. This type of utility may be used to supervise, monitor, and manage a large installed base of solar panel systems (4000) spread out over a large geographic area.

Figure (9) shows a general daily motion profile of a two-axis system - Many different motion profiles can be programmed for the daily sun tracking function and stow positions can be incorporated for nighttime, high wind, snow, or other conditions. Both single and dual-axis systems can be configured. In the morning, a dual axis system may position the solar panels to the sunrise position (4800) before the sun rises. Here, the solar panels (4900) are positioned close to vertical and turned to face the sunrise position. As the sun travels along its path (5000), both the azimuth and elevation of the solar panels (4900) are periodically adjusted to face the sun. At the mid day position (5100) the solar panels (4900) have their maximum vertical elevation of the day and they are facing due south. At the end of the day position (5200) the solar panels (4900) are once again nearly vertical and facing the sunset in the West. For nighttime storage, the panels are re-positioned to face the rising sun for the next day and then the cycle will repeat itself. Other storage positions are possible for the night or adverse weather conditions. It may be desirable to stow the panels in the horizontal position to avoid excess wind loading that can occur overnight.

The motion profiles for a single-axis system are much simpler as the panels are at a fixed inclination and the mount is only rotated throughout the day to the azimuth of the sun.

Figure (10) Passive wind load reduction - This illustration shows how solar panels are mounted on a support structure with an offset pattern designed to reduce wind loading by providing gaps between panel sections. A tubular support structure (5300) provides a mating connection to a rotating mount and supports the side frames (5400) where the solar panels (5500) are attached. The solar panels (5500) are attached to the side frames (5400) with a staggered pattern that creates open panel gaps (5600) between each of the panel sections. These gaps provide a wind relief passage to decrease the overall wind loading on the panel and mounting structure. Many different gap configurations are possible and anticipated by this invention. Examples of these configurations include simple stair step gaps, reverse stair steps, gaps of increasing dimensions, non-linear gaps, gaps with shaped edges, and combinations thereof.

Figure (1 1) Compliant wind load reduction - This illustration shows how a mounting structure can provide passive compliance for each of the panels to relieve overpressure and decrease overall wind loading forces. With this approach, the mounting frame (5700) supports pivot rods (5800) for each of the solar panels (5900). The hinged pivot rods (5800) are located off-center on the solar panels (5900) (here, at the top) and are spring loaded so that they seek a center of rotation where all of the panels lay flat in the same plane as the mounting frame (5700).

Wind causes pressure on the solar panels (5900) with a center of force that is offset from the centerline of the pivot rod (5800). At low wind levels (6000) the force on the solar panels (5900) is not sufficient to cause them to rotate against the spring loaded pivot rods (5800). However, excessive wind speeds (6100) create sufficient force to overcome the spring loaded pivot rod (5800), causing rotation about the pivot rod (6200). This rotation of the solar panel (5900) will decrease its apparent surface area and limit the force of the wind on the panel array to an acceptable level.

Figure (12) Active wind load reduction - This illustration shows how a 2 axis tracking mount may actively re-orient the panels to a horizontal position to reduce wind loading effects. When the solar panels are in a normal position (6300) their surface area may be perpendicular to the apparent wind direction (6400). In this position, the wind forces may be significant. To reduce these forces the solar panels may be re-positioned into a horizontal stow position (6500), where there is very little surface area exposed to the apparent wind direction (6400) and wind loading is greatly reduced. Positioning of the solar panels is performed by the microprocessor-based controller and many different control inputs are possible and anticipated to signal the microprocessor to re -position the solar panels into a horizontal or "stow" position (6500). Strain gauges, pressure sensors, wind speed gauges, or external RF may all be used to trigger the mounting system to move the panels into a safe position.

Figure (13) Utilization of available surface area for advertising - This illustration shows how the available surface area may be used for advertising to help offset the costs of the solar power generation system. Solar power generation has a marginal economic rate of return with current technology and associated costs. Utilization of the available surface area for advertising provides an attractive source of additional revenue. The solar panels may have underside graphics (6600) applied to form an interesting visual display for a variety of commercial enterprises.

To accommodate the needs of different advertising customers, graphic panels (6700) may be inserted into holder frames (6800) that may be easily changed out for periodic updates.

Front surface graphics (6900) may also be applied directly to the face of the solar panels using standard techniques for "see through" images, however care would be required to minimize any associated decrease in solar panel performance.

Figure (14) Wind Turbine Pole mounted sun tracking solar panel mount - This illustration shows a sun tracking solar panel mount installed on a wind turbine pole. Co-locating a tracking solar panel on a wind turbine pole provides a cost effective "hybrid" system that can effectively harvest two different sources of energy, wind and solar. Power generated by both of these systems can be combined for use or storage.

In this illustration, the sun tracking mount and solar panels (7000) are shown mounted to the mid-section of a wind turbine mounting pole (7100). The wind turbine (7200) is positioned at the top of the support tower.

The invention is not limited to the particular embodiments illustrated in the drawings and described above in detail. Those skilled in the art will recognize that other arrangements could be devised, for example, using various fastening mechanisms, solar panel mounting shapes and structures, solar panel support panels, solar panel sizes and shapes, bearing structures, actuators, tracking profiles, and sensors. The invention encompasses every possible combination of the various features of each embodiment disclosed. One or more of the elements described herein with respect to various embodiments can be implemented in a more separated or integrated manner than explicitly described, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. While the invention has been described with reference to specific illustrative embodiments, modifications and variations of the invention may be constructed without departing from the spirit and scope of the invention as set forth in the following claims.

Claims

What is claimed:

1. A tracking mount device, comprising:

one or more split clamping rings having central openings, each comprising two or more bearing sections;

fastening structures configured to secure the split clamping rings to a central object; and a tracking mount configured to rotatably mate with the split clamping ring bearing sections to secure the tracking mount to the central object without being installed over either end of the central object;

wherein the tracking mount is configured to rotate around the central object on the split clamping ring bearing sections.

2. The tracking mount device of claim 1, wherein the tracking mount further comprising a solar panel mounting structure attached to the tracking mount and configured to attach to one or more solar panels.

3. The tracking mount device of claim 2, further comprising a linear actuator configured to rotate the solar panel mounting structure about an axis perpendicular to the major axis of the central object.

4. The tracking mount device of claim 1, further comprising a motor configured to rotate the tracking mount around the central object on the split clamping ring bearing sections.

5. The tracking mount device of claim 1, further comprising a control system configured to control rotation of the tracking mount around the central object.

6. The tracking mount device of claim 1, wherein each split clamping ring's bearing sections comprises one or more bearing surfaces and the tracking mount comprises rollers configured to rotatably mate with the bearing surfaces.

7. The tracking mount device of claim 1, further comprising one or more inserts configured to be secured to one or more of the split clamping rings in the central openings to reduce the effective internal diameter of the split clamping rings or change the shape of the central openings to accommodate smaller diameter or differently-shaped central objects.

8. The tracking mount device of claim 5, wherein the control system is configured to periodically update the position of solar panels attached to the tracking mount to track the sun by rotating the tracking mount around the central object.

9. The tracking mount device of claim 8, wherein the control system is configured to periodically update the position of solar panels attached to the tracking mount to track the sun by rotating the solar panels about an axis perpendicular to the major axis of the central object.

10. A solar energy collection system, comprising the tracking mount device of one of claims 1 to 9 and further comprising one or more solar panels attached to the tracking mount.

1 1. The solar energy collection system of claim 10, wherein the solar panels are positioned such that they are not between the pole and the sun.

12. The solar energy collection system of claim 10, wherein a control system is configured to detect unsafe forces on the solar panels based on sensor inputs and rotate the solar panels into a stow position.

13. The solar energy collection system of claim 10, further comprising batteries configured to store excess electrical power.

14. The solar energy collection system of claim 10, further comprising a grid tie inverter configured to convert excess electrical power to AC power and feed it back into an electrical grid.

15. The solar energy collection system of claim 10, wherein a control system is configured to provide excess electrical power to an energy storage device.

16. The solar energy collection system of claim 10, wherein the solar panels are mounted at a fixed elevation angle

17. The solar energy collection system of claim 10, wherein the solar panels are configured to pivot to relieve excessive wind load forces.

18. The solar energy collection system of claim 10, wherein a surface of the solar panels or a support frame comprises graphics for promotional purposes.

19. The solar energy collection system of claim 10, wherein the pole is a vertical support pole for a wind power turbine.

20. The solar energy collection system of claim 10, wherein the solar panels are mounted on a support structure in an offset pattern, providing gaps between solar panel sections to reduce wind loading.

21. A solar energy collection method, comprising:

placing a split clamping ring having bearing sections around a central object;

clamping the split clamping rings to the central object to form a split ring bearing around the central object; and

rotatably mating a tracking mount with the split ring bearing and securing the tracking mount to the central object without installing the tracking mount over either end of the central object.