GB2623650A

GB2623650A - Floating solar apparatus

Info

Publication number: GB2623650A
Application number: GB2316222.5A
Authority: GB
Inventors: Cojoc-Wisernig Eduard
Original assignee: Wiser Marine Tech Ltd
Current assignee: Wiser Marine Tech Ltd
Priority date: 2022-10-21
Filing date: 2023-10-23
Publication date: 2024-04-24
Also published as: GB202316222D0; GB202215672D0; CA3217537A1

Abstract

An apparatus for solar power generation comprising a floating platform having a tensegrity structure, a solar panel, and attachment means connecting the solar panel to the floating platform. The floating platform may have a plurality of frames vertically spaced apart from each other and connected by cables. The plurality of frames may comprise a lower floating frame, a middle frame concentric with and set inward from the floating frame, and a top frame having said attachment means. The frames may be triangular, and a first set of cables may connect vertices of one of the frames to the vertices of another of the frames. A midpoint cable may be from vertices of one triangular frame to the midpoint of the next triangular frame. The plurality of frames may be concentrically arranged in plan-view. A floating solar farm comprising a plurality of said apparatus, electrically and physically connected as an array.

Description

TITLE: Floating Solar Apparatus

RELATED INVENTIONS

[0001] The present invention claims priority to UK patent application GB GB2215672.3 filed 21 October 2022.

FIELD OF THE INVENTION

[0002] The invention relates generally to solar apparatus, in particular, solar apparatus deployed in coastal areas.

BACKGROUND OF THE INVENTION

[0003] Solar panels have become an increasingly popular form of renewable energy over the past few decades due to their ability to generate electricity from the sun's rays. The development of solar panels can be traced back to the 19th century when French physicist Alexandre-Edmond Becquerel discovered the photovoltaic effect, which is the process by which a material produces an electric current when exposed to light.

[0004] Throughout the 1980s and 1990s, advancements in materials science and manufacturing techniques led to the development of more efficient and cost-effective solar panels. Today, solar panels are used in a wide range of applications, from powering homes and businesses to providing electricity to remote areas without access to the power grid.

[0005] As the demand for renewable energy continues to grow, there is a need for further innovation in the field of solar panels. They are ideally placed near to the communities that use the power and therefore need to be installed in a position and attitude for maximum solar exposure. Typically, solar panels are placed in large open fields, on buildings, or other rigged bases.

[0006] The inventor has appreciated that coastal communities, which may be remote from the power grid, have an abundance of space in their harbours. While harbours have the advantage of sun exposure, the disadvantage is exposure to waves. The motion of the waves is likely to affect the position and attitude of any solar panel or indeed the motion may break such a solar installation.

SUMMARY OF THE INVENTION

[0007] In accordance with a first aspect of the invention there is provided apparatus for solar power generation comprising: a floating platform having a tensegrity structure; a solar panel; and attachment means connecting the solar panel to the floating platform.* [0008] The floating platform may have a plurality of frames vertically spaced apart from each other and connected by cables. The plurality of frames may comprise a lower floating frame, a middle frame concentric with and set inward from the floating frame, and a top frame having said attachment means. The frames may be triangular and a first set of cables may connect vertices of one of the frames to the vertices of another of the frames.

[0009] A midpoint cable from vertices of one triangular frame may connect to the midpoint of the next triangular frame. The plurality of frames may be concentrically arranged in plan view.

[0010] The apparatus may comprise a battery system for storing power from the solar panel.

[0011] The apparatus may comprise an actuator connected to the solar panel and arranged to change the attitude of the solar panel relative to the floating platform.

[0012] A floating solar farm may be formed from a plurality of the apparatus modules of being electrically and physically connected together as an array.

[0013] The whole arrangement floats in protected harbours and is capable of maintaining the solar panel at an optimal angle for power generation, despite waves moving the lower one of the frames.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Various objects, features and advantages of the invention will be apparent from the following description of embodiments of the invention, as illustrated in the accompanying drawings. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of various embodiments of the invention. -2 -

FIG. 1 is the upright triangular frame and single-axis solar panel tilt assembly details.

FIG. 2 is the inner triangular frame assembly details.

FIG. 3 is the full tensegrity solar power system assembly details.

FIG. 4 is a sideview of the solar power system.

The figures are provided with reference numerals using the following key:

Item no. Description

1 Inner frame body 2 Vertical triangular frame 3 Corner plates 4 Midway attachment plates Attachment hardware 6 Upper frame extrusion 7 Solar panel array assembly 8 Actuator extension bracket 9 Lower frame extrusion Stainless shrouds 11 Actuator brackets 12 Electric linear actuator 13 Floats 14 Flexible keel (3D bridled dead weight) Outer frame body

DETAILED DESCRIPTION OF THE INVENTION

[0015] With reference to the attached drawings, preferred embodiments of the present provide apparatus for mounting a solar panel on a floating frame intended for placement on a body of water. Ideally the body of water is a protected body, such as a harbour. The apparatus includes a tensegrity structure to mount the solar panels in a self-balancing way, which provides the advantage of keeping the solar panel facing the sun despite the motion of the waves on the floats.

[0016] The tensegrity structure has three triangles suspended in three-dimensional space using stainless-steel cabling which is attached between each of the adjacent vertices. The upright triangular frame (Fig. 1) provides a horizontal attachment point to which the solar panels can be mounted and distributes the loading to each of the wires attached at the -3 -vertices. The stainless-steel cable provides the structure with significant load capacity as the loads imparted on the inner triangular frame (Fig. 2) are converted into tensile loads. The preloading characteristics of the stainless cables vary depending on the environment it will be used in. The stainless-steel cable also provides flexibility to the structure due to the elasticity of the cables. This flexibility increases the expected lifetime of the structure as it serves to dampen the effects of cyclical loading on the frame due to wave action and wind loading. This structure is extremely resistant to loads that attempt to skew, translate, or rotate the inner triangular frame with respect to the outer triangular frame (Fig. 3).

[0017] Tensegrity consists of a system of isolated rigid members under pure compression inside a network of continuous pure tension. True tensegrity structures are arranged such that the compressed members (typically struts) do not touch each other while the tensioned members (cables) separate the system spatially. Due to the pure tension and compression present in a tensegrity structure, there are no bending moments or shear stress within the system. This allows these structures to be lightweight, extremely strong, and rigid.

[0018] The balanced platform is created by the interaction of the tension and compression forces in the structure. The tensioned cables (Fig. 2, 7-11) or rods provide a continuous and even distribution of forces throughout the structure. This allows the struts to remain in a state of tension, which in turn provides a stable and self-balancing platform. The tension in the cables or rods provides a counterbalance to the compression forces in the struts, allowing the structure to maintain its shape and stability even when exposed to external forces, such as waves.

[0019] The tensegrity structure is also able to distribute loads efficiently across the structure. This is due to the tensioned cables or rods, which can absorb and distribute loads in a way that is more efficient than traditional compression-based structures. Thus using a tensegrity structure for the solar platform provides a balanced and self-stabilizing platform that is efficient and effective in distributing loads across a structure.

[0020] Utilizing two-dimensional triangular compression members in a tensegrity network provides a suitable frame to which solar panels can be attached. The attachment of the -4 -triangles to each other is performed using the same methods used for Marconi rigging in sailboats using stainless cable and turnbuckles.

[0021] The inner triangular frame (Fig. 2, 1) and upright triangular frame (Fig. 1, 1) are fully constrained within the plane due to the presence of tensioned stainless-steel cabling attached from the midpoint of each the inner frame length to the outer frame (Fig. 3, 2) vertices. This provides rigidity and resistance to movement between the two frames within the plane but also allows the inner triangle to rotate freely in or out of the plane. Using this type of system serves to reduce the torsional and bending effects of large waves on the inner frame.

[0022] An optional single mass is suspended below the inner frame from stainless-steel cables which are attached to each of the vertices of the inner frame. At each of the inner frame vertices there is floatation which counteracts any moment or rotation into or out of the plane. The suspended mass provides a method to strategically reduce loading on specific areas of the structure during large waves when the inner frame would begin to rotate. When a float begins to submerge, the mass increases tension on the cables which are not submerging, while reducing all tension loading on the semi-submerged float. The mass is selected such that its gravitational force in water is equal to the buoyancy force of a single float (each float takes 1/3 mass). The inner triangular frame can freely rotate in and out of the plane up to a limit of approximately 300 angular displacement. The skilled person may see this as a vertical 3D bridle, like the bridles 2D horizontal you find on a tug and barge towing line.

[0023] This structure provides a large weight distribution over a large area while also minimizing the amount of tensegrity compression members to three. Compared to other tensegrity structures, preferred embodiments provide convenient attachment points for both the solar panels and the floatation due to the orthogonal geometry. The tensegrity structure also provides wave-damping in the form of two co-planar triangles suspended using stainless-steel cabling. The larger outer frame provides an anchoring point for the system and provides inertia to the system due to its large mass, providing stability during harsh environmental conditions. -5 -

[0024] The linear actuator features a potentiometer that is read by the microcontroller. The microcontroller energizes the linear actuator based on a PID controller to achieve the desired position of the actuator (based on inputs from the panel orientation sensor) [0025] The solar panel module is mounted on the tensegrity structure and to controllable actuators that allow the solar panel to change its position with respect to the sun.

[0026] A control module monitors the position of the sun and adjusts the attitude of the solar panel accordingly. The control module operates based on a set of algorithms that optimize the efficiency of the solar panel system, ensuring that the solar panel is always positioned to receive the maximum amount of sunlight. In high latitude locations, the sun is often low on the horizon, so the solar panel should face much lower than typical solar collectors, which generally face upwards. Otherwise very little electricity will be generated. Locations such as Canada, Scotland, Norway are exemplary in that the sun is low, there are many protected harbours, and their coastal communities may be off-grid.

[0027] The control module can be connected to a user interface module that allows users to monitor the performance of the system in real-time, adjust settings, and receive alerts in the event of a malfunction or system failure.

[0028] The solar panel system can be designed to operate in a single-axis or dual-axis configuration. In the single-axis configuration shown, the solar panel is able to pitch around a single axis (from horizon to upwards) to follow the path of the sun over the seasons. In a dual-axis configuration, the solar panel is able to rotate around two axes to track the sun's position in both the horizontal and vertical planes. Once the modules are assembled into a floating array with several modules, the array has thrusters that provide horizontal axis movement. Individual module horizontal control is possible, but likely financially unfeasible due to high costs for thrusters. In a preferred embodiment, each solar power module has a single, vertical-axis control and the horizontal axis control for the whole array uses one or more thrusters.

[0029] Depending on the application (sheltered bay vs. open ocean), the float attachments are variable. For a sheltered bay, the floats are heavy-duty plastic drums filled with marine-resistant foam; they are designed to be attached in the corners of both -6 -of the inside and the outside triangles. The triangle's corners are subdivided into much smaller triangles that fit around the drums, holding them in place. They are attached to the triangles using heavy-duty marine lashing, to reduce strain on the drum and to increase flexibility.

[0030] Depending on the configuration, either each module is anchored to the sea bed, or the modules are assembled in a large floating platform that is anchored in just one point with a swivel, and the assembly can perform horizontal axis tracking using a thruster.

[0031] Passive stabilization is achieved using a flexible keel, with a dead weight that moves its downward force to the most elevated corner of the triangle.

[0032] The apparatus may transfer electricity to shore via power cables or store the electricity onboard in batteries. The apparatus itself may even have devices that are the sink for the electricity generated thereon. For example, there may be motors powering propellers in the water for moving and orienting the apparatus. The apparatus may have lighting that draws power from the co-located solar panels. As known to the skilled person the apparatus will have battery management systems or power management systems (PMS), as appropriate, to control the supply and demand of electricity.

[0033] The apparatus utilizes the PMS for managing the power generated by the solar panel. The solar panel may be connected to a power inverter module, which converts the DC electricity generated by the solar panel module into AC electricity suitable for use in commercial or residential buildings.

[0034] The power management system includes a monitoring module that monitors the output of the solar panel module, as well as the energy consumption of the power sink. The monitoring module is connected to the batteries, which can store excess energy generated by the solar panel module for later use. The power storage module can be a battery bank or other energy storage system, such as a flywheel or a supercapacitor.

[0035] The power management system includes a control module that regulates the flow of electricity between the solar panel module, the power inverter module, and the power storage module. The control module operates based on a set of predetermined algorithms -7 -that optimize the efficiency of the system and ensure that the electricity demand always has a reliable source of electricity.

[0036] The system also includes a user interface module that allows users to monitor the performance of the system in real-time, adjust settings, and receive alerts in the event of a malfunction or system failure.

[0037] Each solar module may have its own power system that includes: linear actuator; tilt/orientation sensor; microcontroller with networking capabilities; small battery; battery management system. Every module is preferably autonomous, and will control the attitude (e.g. tracking sun altitude) of the solar panels. The microcontroller reads the current tilt of the panels and moves the linear actuators until the desired new tilt is achieved. Each module may charge its own small battery backup directly from the solar panels and does not require external power.

[0038] After connectivity is lost for a certain amount of time, the modules go into failsafe mode, tilting the panels horizontally, to significantly reduce wind drag.

[0039] An array assembly of plural solar modules may have additional features: an Internet connection; astronomical information processing server for determining sun's position for a given day/time; a large battery bank (i.e larger than the battery of each module's battery); large-capacity battery management system; central fuse panel / solar panel input hookups. A remote astronomical server broadcasts information regarding the desired angles for the array or a solar panel for a given day.

[0040] While the invention is described herein in the simplest form of a single solar panel on a single floating frame, the skilled person will appreciate that this can be scaled up by having plural solar panels per floating apparatus and/or connecting plural floating apparatus as a network. Then the network can share batteries, power controllers, anchors, and power cables to the demand for electricity. -8 -

Claims

CLAIMS: 1 An apparatus for solar power generation comprising: a) a floating platform having a tensegrity structure; b) a solar panel; and attachment means connecting the solar panel to the floating platform.
2. The apparatus of claim 1, wherein the floating platform has a plurality of frames vertically spaced apart from each other and connected by cables.
3. The apparatus of claim 2, wherein the plurality of frames comprises a lower floating frame, a middle frame concentric with and set inward from the floating frame, and a top frame having said attachment means.
4 The apparatus of claim 2, wherein the frames are triangular and a first set of cables connect vertices of one of the frames to the vertices of another of the frames.
5. The apparatus of claim 4, further comprising a midpoint cable from vertices of one triangular frame to the midpoint of the next triangular frame.
6. The apparatus of claim 2, wherein the plurality of frames are concentrically arranged in plan view.
7 The apparatus of claim 1, further comprising a battery system for storing power from the solar panel.
8 The apparatus of claim 1, further comprising an actuator connected to the solar panel and arranged to change the attitude of the solar panel relative to the floating platform.
9. A floating solar farm comprising a plurality of the apparatus of claim 1 electrically and physically connected together as an array. -9 -