Solar energy collector with truncated pyramid configuration

Abstract

A solar energy collector for converting solar energy to electricity includes a hollow body having an internal structure of a truncated pyramid or conical frustum; a plurality of substantially vertically stacked photocells arranged on two or more faces of the internal structure; a concentrator having a conical or a pyramidal shape with a predetermined slant or tip angle; and a plurality of reflecting surfaces. The photocells may be mounted on alternating faces of the body. The faces of the body not having photocells may be at least partially open and allow sunlight therethrough. One or more reflecting surfaces, oriented toward an interior of the hollow body, is arranged within one or more of the at least partially open faces. The photocells may be inwardly tilted to an internal angle between 70 and 89.9⁰.  The concentrator may be configured for dynamic movement and angle adjustment relative to the body.

Description

SOLAR ENERGY COLLECTORWITH TRUNCATED PYRAMID CONFIGURATIONRELATED APPLICATIONSThis application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 614,695, filed December 26, 2023, entitled “Solar Energy Collector,” the contents of which are hereby incorporated by reference as if fully set forth herein. TECHNOLOGICAL FIELDThe invention generally concerns solar power generators and methods of use for generating electric power. BACKGROUNDPhotocells are commonly utilized in the domestic and the industrial arenas to convert solar radiation into electrical energy. While a great variety of novel systems and methodologies have been developed for minimizing the traditional deficiencies associated with conversion of solar radiation to electricity, some still exist which are mainly associated with the fact that solar radiation is a dynamic process that depends on the geographic location and atmospheric conditions. With performance and efficiency of existing radiation collectors changing with time, the need for an efficient system that is stable and which can adapt to varying radiation and atmospheric behaviors is still an unmet need.One challenge facing the solar energy sector is the need for efficient utilization of space. Typically, solar energy is harvested using arrays of photovoltaic panels. The photovoltaic panels are oriented at a standard angle relative to horizontal (for example, 27°). Some photovoltaic panels are equipped with the ability to track movement of the sun; nevertheless, for a substantial portion of the day, the panels are required to be positioned at an angle that is close to horizontal. As a result, the photovoltaic panels occupy a relatively large amount of space. This space comes at the expense of other uses of the land, such as planting of crops or grazing of livestock. While some systems for arranging for agricultural use of land underneath solar panels have been proposed, these systems have not yet achieved the desired efficiency to enable widespread implementation.One known solution for maximizing the solar energy obtained relative to surface area utilized is a solar energy collector. Solar energy collectors are substantially cylindrical or funnel-shaped bodies. The interiors of the bodies are lined with solar panels, and include a reflective concentrator at the center of the cylinder. The concentrator reflects incident light from the interior of the collector to the solar panels that form the body of the collector. This reflection of the incident light from the concentrator is directed to maximize the energy obtained from the incident sunlight. Some examples of solar energy collectors are described in the references cited below.References: IN2022 / 1064716, US2021 / 0257695, US2018 / 0278203, WO2014 / 133806. SUMMARY OF THE INVENTIONThe present disclosure introduces an improved solar energy collector. The improved solar energy collector has structural characteristics that maximize its ability to capture solar energy relative to both conventional solar fields and even to previously known models of solar energy collectors. In particular, the structural characteristics include the shape and orientation of the solar panels that comprise the walls of the solar energy collector, the strategic placement of openings among the walls of the solar energy collector, and the ability of the concentrator to track the sun.With respect to the shape and orientation of the solar panels, the disclosed collector comprises a body or an enclosure generally shaped as a polygonal cylinder, having a shape of a truncated pyramid or a conical frustum. As used in the present disclosure, the term “pyramid” refers to a polyhedron with a polygonal base and converging to an apex. A truncated pyramid is a pyramid that is cut by a plane parallel to the base, such that the top is a polygon having the same number of sides as the base. For the avoidance of doubt, the terms “pyramid” and “truncated pyramid” are not limited to pyramids having rectangular bases.The body has a polygonal structure with a plurality of faces (the number of which defining the particular polygonal structure used), which may be of the same or different lateral lengths. At least some of the faces include one or more photocells (e.g., a photoemissive surface, a photovoltaic surface, a photoconductive surface, etc.). At least some other of the faces are open, permitting sunlight therethrough. A concentrator is provided in said body and is configured to reflect incident light onto the panels. The concentrator is configured to be movably guided to maximize focusing of sunlight onto the photocells and allow conversion of the solar radiation to electric power.Having a shape that is generally conical or of a truncated pyramid, wherein walls of the body are inwardly tilted (to an internal angle that is smaller than 90⁰, e.g., is between 70 and 89.9⁰), causes solar radiation entering the body of the collector to become trapped and internally reflected. This trapping of the incident light maximizes reflection of light onto the photocell assembly and increases energy production. In addition, the truncated pyramid shape provides the solar panel collector with mechanical stability. This mechanical stability helps protect from damage from high winds, for example.In particularly advantageous embodiments, the photocells are arranged on alternating faces of the body. The faces of the body that do not have photocells are open, to permit sunlight therethrough. The number of faces in total may be any number, typically from 4 to 16, and the number of openings for light may be correspondingly half that number, e.g., from 2 to 8. The relatively large number of openings helps ensure that light may enter from multiple angles. In addition, the openings serve an additional function of dissipating heat from the solar energy collector.The combination of the openings for sunlight, the substantially conical or pyramidal shape, and the concentrator enables capture of sunlight when the sun is at low angles relative to the solar energy collector. This sunlight enters the collector via the openings, and is reflected by the concentrator onto the inwardly tilted walls of photocells. In addition, the opening at the top of the soler energy collector enables collection of solar energy from above.The open faces may optionally include, at least in part, reflective surfaces. These reflective surfaces may further assist in the trapping of solar energy within the solar energy collector.Thus, in one embodiment, the solar energy collector comprises: a hollow body having an internal structure of a truncated pyramid or frustum; a plurality of substantially vertically stacked photocells arranged on two or more faces of the internal structure; a concentrator having a conical or pyramidal shape with a predetermined slant or tip angle; and a plurality of reflecting surfaces.The internal structure of the body may be a polygonal structure with a number of walls between 2 and 16. In such embodiments, the photocells may be arranged along at least two alternating, non-adjacent faces of the polygonal internal structure, such that each of the at least two non-adjacent faces comprise vertically stacked photocells, each facing the concentrator, and optionally one or more additional reflective faces. In some configurations described herein, each of the plurality of photocells mounted on the at least two non-adjacent internal faces of the collector may be separated by a face of the polygon that is at least partially open, to allow sunlight therethrough. The at least partially open faces may include one or more reflecting surfaces, oriented toward an interior of the hollow body. As the body of the collector is generally inwardly angled (to provide the generally conical shape), the vertical stacking refers to photocells that are aligned one above the other along the long axis of the body internal walls and at an angle that is substantially the same as the angle of the body walls.The internal angle of the hollow body defined by the stacked photocells may be between 70 to 89.9°. In some configurations, the stacked photocells are fixed in place. In other configurations, the stacked photocells may optionally be independently and individually be addressable to maximize a photocell reorientation or repositioning with respect to incoming solar radiation.The base end is provided or mounted with a concentrator. The concentrator is a circular-base conical or pyramidal concentrator having a slant angle or a tip angle that is selected to effectively focus incident light onto one or more regions of the photocells.In some configurations, the slant / tip angle may be selected such that the height of the concentrator is at least one half of the height of a top-end of the highest photocell mounted in the assembly. In other configurations, the concentrator height may be approximately 10-30% the height of the highest photocell in the assembly. The height of the concentrator may be determined, inter alia, based on the slant height of the body and the size and shape of the openings within the body. Irrespective of the concentrator height, the concentrator may have an external surface (namely the surface that is to focus or reflect the solar radiation) that is continuous or that is formed of a plurality of independent elements, wherein each of the independent elements may be individually addressable. The surface of the concentrator or each of the elements making up the external surface thereof is formed of a reflective material. The reflective material of the concentrator surface may or may not be the same as the material of the reflecting surfaces mounted on some of the internal walls of the assembly body.In exemplary embodiments, the concentrator is movable. Specifically, the concentrator may be configured for dynamic movement and angle adjustment relative to the body. The movement of the concentrator may be specifically programmed in order to track movement of the sun.The concentrator may be mounted on a movable surface or a lift such that at least one of its positional vectors may be varied. The positional vectors may be any one or more of:-a position of the concentrator within the collector assembly relative to the center of the collector base,-a tilt angle of the concentrator with respect to a vertical axis of the collector’s body, and-a distance between the base of the collector to the tip end of the concentrator.Movement of the concentrator may allow to move the concentrator along any axis of the body, i.e., along the x-axis or y-axis (changing the concentrator position relative to the center of the body), the z-axis (changing the distance measured from the internal base to the concentrator tip) and the angular orientation (changing the tilt angle of the concentrator, whereby an axis extending from the base of the concentrator to its tip is not perpendicular to the collector’s base but rather is tilted in a direction of the reflecting surfaces or the photocells). In other words, the concentrator may be configured to rotate, tilt, or change position so as to change or modify a deflection angle of the concentrator in relation to the internal polygonal structure. The movement of the concentrator may be limited only by a control system based on a selected or changing operating conditions or operating protocols.The dimensions of the solar energy collector of the invention may vary. Typically, the collector is a polygonal structure of the convex form having at least five sides or faces, at least two of the polygonal internal faces having a grid-like structure defining a plurality of spaces or frames for receiving and holding a plurality of photocells. The grid-like structure allows for stacking the photocells in a vertical orientation to any height. Typically, the height of the collector body allows for vertically stacking at least three (or between 3 and 20) stacks of photocells. Theoretically, there is no limit to the number of photocells in each stack, subject to engineering limitations.As will be further disclosed herein, the collector has demonstrated superiority in maximizing solar power generation using sunlight that is directly incident to the photocells, and by sunlight that is reflected by the reflecting surfaces or the concentrator. The collector of the invention is configured and operable to increase solar energy capture efficiency, dynamic adaptability to changing sunlight angles, and provides an aesthetically pleasing structure suitable for diverse environments.The photocells may be any one or more of the solid-state devices known in the art to convert light into electrical energy by producing a voltage. In some embodiments, the photocells may be in a form of a photoemissive surface, a photovoltaic surface, or a photoconductive surface of any type (including standard and bi-facial photocells). In some configurations, the collector may comprise a plurality of different photocells, each selected based on its sensitivity, size, material composition, etc.In preferred embodiments, the photocells are bifacial. The bifacial photocells have a more efficient face and a less efficient face. The more efficient face is oriented toward an outside of the body, and the less efficient face is oriented toward an inside of the body. Advantageously, in such embodiments, the more efficient face of each bifacial photocell receives direct sunlight. The less efficient face receives reflected sunlight via the concentrator. Utilized in this way, each face of the bifacial photocells receives maximal sunlight, and the bifacial photocells generate a comparatively high output of energy relative to surface area.Irrespective of the type of photocells used, the photocells are typically stacked one above the other to any height, or to fully or at least partially cover two or more internal walls of the polygonal structure. Typically, the photocells are mounted on alternating walls of the structure. A reflective surface may be provided on a wall separating any two walls with mounted photocells. Typically, the polygonal structure has an even number of walls, e.g., hexagonal or octagonal structure, so that any two walls mounted with the photocells are separated by a reflective wall, in an alternating manner. Nevertheless, the number of walls may be at least 5, at least two of which being mounted with photocells. In some embodiments, the polygonal structure is a 6-, 7-, 8-, or 9-or greater number (up to 16) sided polygon.In some configurations, each of the polygonal walls may be mounted with the photocells, wherein a top lateral region of the collector, optionally provided immediately below a top end of the collector is provided with an array of reflective surfaces which improve reflection of solar radiation inwardly. In addition or in the alternative, a bottom lateral region of the body of the collector may be provided with reflective surfaces. In still another alternative, the bottom surface of the collector, surrounding the concentrator, may be provided with a reflective surface.In further configurations, reflective surfaces may be provided in certain predesigned regions of the collector and may vary based on the condition of collector assembly.Each of the photocells may include static placement or may be individually addressable so that their orientation or angle with respect to the concentrator may be adjusted. Each photocell may be mounted on a frame of a grid structure, wherein the frame provides the photocell with stability with an optional tilt or reorientation mechanism. The frames may be interconnected frames, each provided with a fixing means for locking the photocells within. The size of each frame may depend on the size of the photocell to be used, which may vary and is unlimited.The photocells may be grouped based on their type or based on their position in the collector. For example, the photocells may be divided into a number of groups corresponding to the number of walls mounted thereby, wherein each group comprises a plurality of vertically stacked cells. Each such group may be equipped with dedicated wiring and other electric units. All photocells in a group may be wired in series (wherein the positive of one photocell is connected to the negative of another photocell). In such a configuration, each group of photocells may have a positive and a negative terminal. Alternatively, the photocells may be connected in parallel.In some configurations, the photocells are wired directly to a central power management system, which allows wiring according to a preferred design, e.g., allowing a parallel connection, a connection in series, and further optionally central control and management including disconnection-connection and control output optimization.As discussed, positioned within the collector is a light concentrator which may be conically shaped and is designed to focus and direct sunlight onto the photocells. The conical shape facilitates the concentration of sunlight, enhancing energy conversion efficiency, which is further enhanced by a mechanism allowing for movement and angle adjustments. The movement of the concentrator may be governed by a sun tracking system that is configured and operable to automate the adjustment process, or may be programmed based on the location of the collector, its height, season and other variable factors.The mechanism for causing movement of the concentrator is not limited and any known mechanism can be employed. The driving means may be motors, and a motor such as a stepping motor which can control a rotation angle constitutes an embodiment. Each driving means may be electrically connected to the sun tracking system, and is operated in response to signals output from the tracking system.An energy storage system, such as batteries, may be integrated to store excess energy for use during low sunlight conditions. A power conversion system may be integrated to convert the direct current (DC) electricity generated by the photocells into alternating current (AC), suitable for common electrical applications. The collector may also have a distribution system to transmit the generated electricity to desired locations or an electrical grid.The collector may further include sensors and monitoring systems to track proper performance of the photocells, the concentrator movement, and environmental conditions. A control system may be in place to manage the automated adjustments of the photocells and the concentrator for optimal operational efficiency.As stated herein, the collector may be erected such that one of its ends defines a base end and another defines a top opening. Light enters the collector from its top opening, as well as from its side openings, for the amplification of any light projected to any inner photocell and mirrors arrangements. Light also contacts the exterior faces of the solar panels, in the case of bifacial panels.To prevent collection of dirt that may affect light transmission, the solar tower may be provided with an automatic cleaning member such as an arcuate wiper or a cleaning robot. The solar tower may include any automatic cleaning system such as angular spray, moving robotic cleaning wipes etc. The cleaning member may be automatically operated and may involve sensors and a monitoring system.Optionally, a dome structure is provided at a top end of the tower. The dome may be formed of a shape of a hemisphere or half a geodesic faceted structure. The dome may be formed of a transparent material that exhibits a minimal light reflection or absorption and maximizes light entry to the collector. The dome may be equipped with an automated cleaning member configured and operable to maintain maximal transmission of light through the dome.The invention further provides a solar field or a solar array provided with a plurality of solar collectors according to the invention.In another aspect, there is provided a movable concentrator having a continuous light reflective surface or a reflective surface formed of a plurality of reflective members, wherein each or a plurality of the reflective members are addressable (individually or as a group) to maximize light incidence onto the reflective members; the concentrator having a base provided with a means for moving the concentrator vertically or laterally and / or for adjusting its angle with respect to its base.In some embodiments, the concentrator is configured for assembly or use in a solar tower or a solar light collector. BRIEF DESCRIPTION OF THE DRAWINGSIn order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:Fig. 1 schematically illustrates a solar collector, according to embodiments of the present disclosure;Fig. 2schematically illustrates another embodiment of a solar collector, according to some embodiments of the present disclosure;Fig. 3 further schematically illustrates a solar collector, according to some embodiments of the present disclosure;Fig. 4schematically illustrates a concentrator, according to some embodiments of the present disclosure; andFig. 5 illustrates schematically a comparison of energy collection over a day using the solar energy collector of the present disclosure, as opposed to typical solar panels. DETAILED DESCRIPTION OF EMBODIMENTSThe invention disclosed herein will now be exemplified, in a first embodiment, by reference to FIG. 1.Referring to FIG. 1, solar energy collector 100 comprises a body 110. The body 110, in the illustrated embodiment, is a tower. The tower is shaped as a truncated pyramid. The octagon is made of four wide faces 111a, 111b, 111c, 111d, each of which contains photocells 114, supported by framing member 112. The octagon further includes four narrow faces 118, which are open, permitting light to enter therethrough. Optionally, the narrow faces are at least partially covered with reflecting surfaces that are directed toward the interior of the collector 100. The wide faces 110 are arranged as two opposing pairs, in which face 111a and 111b are opposing, and sides 111c and 111d are opposing. The four narrow faces 118 are similarly arranged between the four wide faces.The use of an octagonal cross-section is merely exemplary, and, in alternative embodiments, the pyramid may have a different polygonal cross section. For example, the cross section may be hexagonal (6-sided), decagonal (10-sided), or dodecagonal (12-sided), or up to having 16 faces with alternating faces with photocells and openings. Theoretically, the cross-section may also incorporate curves. Likewise, it is not strictly necessary for the open faces to be arranged in sequence around the polygonal cross section, or to have the exact ratio of photocells to open space as depicted in the Figure. In addition, although, in the illustrated embodiment, there is an even number of faces, the number of faces may alternatively be odd.In the illustrated embodiment, the solar energy collector 100 has an opening 116 at the top. Thus, sunlight may enter the solar energy collector 100 through the top opening 116 and through the narrow faces 118. In alternative embodiments, the solar energy collector 100 has a dome-shaped top, which is made of a material that permits sunlight therethrough.Each face 111 is constructed of one or more photocells 114. The photocells 114 may be constructed as panels that are substantially rectangularly shaped. In the illustrated embodiment, there are five photocells 114 on each face, arranged one on top of the other. In alternative embodiments, there may be fewer or more photocells 114 (e.g., between 2 and 12). Optionally, the bottom-most panel of one of the faces 111 does not contain solar cells, but rather is a service panel which may be used to provide access to the interior of the body 110, or may include electrical and control panels, etc. Typically, the service panel is oriented on the northern-facing face 111. Also optionally, one or more of the panels may comprise a reflective surface. For example, the top-most or the bottom-most panel in each face may be a reflective surface. The photocells may have any suitable shape (e.g., square, hexagonal, etc.) and any suitable orientation (e.g., substantially horizontal, or substantially vertical).The faces 111 are inwardly tilted to an internal angle, relative to base 115, that is smaller than 90⁰. This internal tilting serves to ensure that sunlight reflected by the concentrator 120 is trapped within the body 110 and arrives at a photocell 114, as opposed to being reflected completely out of the body 110. Correspondingly, the opening 116 at the top of body 110 has a slightly smaller area than the base 115. In exemplary embodiments, this angle is between 70° and 89.9°. In the embodiment depicted in FIG. 1, the angle is 89°.Solar energy collector 100 further includes a concentrator 120. Concentrator 120 may be based on an inner supporting heavy material (i.e., concrete, steel, etc.) which allows the lowering of the structural moment of inertia under external physical forces over the tower. In the present embodiment, concentrator 120 has a pyramidal shape (having a polygonal base with any number of sides); in alternative embodiments, the concentrator is conical. The function of concentrator 120 is to reflect incident sunlight (sunlight entering the collector 100 from above or from one of the narrow faces 118) onto solar panels from the body 110. Optionally, the bottom surface of the collector, surrounding the concentrator, may also be made of reflective material. There may also be reflective material at the top or bottom of each face containing photocells.Concentrator 120 may be arranged on a platform which may be moved with six degrees of freedom. For example, the platform may be mounted on a plurality of telescopic legs or stilts which may be raised, lowered, extended, retracted, or bent, in order to cause the concentrator 120 to tilt to a desired angle. In addition, the height of the concentrator 120 relative to the photocells 114 may be adjusted according to the height of the sun. As a result, the concentrator may be tilted so as to track the sun and thereby maximize the solar energy that is ultimately received by the photocells.In the illustrated embodiment, the height of the tip of concentrator is approximately 10-30% of the height of the body defined by the photocells. The height and slant angle of the concentrator may be set based on the shape of the faces containing the photocells, and of the open faces and reflectors when present, in order to maximize the reflection of light incident on the concentrator onto the photocells. In addition, as discussed, the concentrator may be movable relative to the body containing the photocells.In preferred embodiments, the photocells are bifacial. A “bifacial” photocell has active photovoltaic surfaces on two faces of the panel – e.g., front and rear. The bifacial panels that are used may be standard, off-the-shelf panels, of any size and dimension. In one exemplary embodiment, the panels are 2m*1m with a depth of 3.5 cm. In such embodiments, the outer face of the panel receives incident sunlight directly, while the inner face of the panel receives both direct incident sunlight via the open faces, as well as reflected sunlight from the concentrator 120. The more efficient face of the bifacial panels may be directed to the outside of the collector, such that it receives direct sunlight. The less efficient face of the bifacial panel may be directed to the inside of the collector, such that it receives reflected sunlight. Advantageously, in such configurations, both sides of the bifacial panel receive maximal sunlight, and the overall efficiency is improved.Optionally, each face 111 of the solar energy collector 100 has a carriage with an automatic cleaning system. The cleaning system may include any optional combinations or elements for cleaning, such as wipers (whether static or driven), water jetting, or water sprinkling. The cleaning carriage may move automatically along the face 111, whether up-down or side to side. Optionally, water for the cleaning system may be self-generated from moisture in the air.Fig. 2 an alternative embodiment of a solar energy collector 200. In this embodiment, instead of the body being comprised of the photocells arranged in a frame-like structure, the body of the collector is a separate enclosure, with the photocells mounted on an interior thereof. Collector 200 comprises a body 120 being an enclosure shaped as a truncated pyramid or a conical frustum. The body 220 has an internal polygonal structure with a plurality of faces (not shown) with a plurality of photocells 210 (each comprising a plurality of photocells) arranged on the internal walls of the collector 200. In this embodiment, the photovoltaic cells 210 do not form the entirety of the walls of the collector 200, but rather are mounted on the walls. The conical shape defines walls that are inwardly tilted to an internal angle A that is smaller than 90⁰. The plurality of photocells 210 are vertically stacked, each facing inwardly. As the body 220 of the collector 220 is generally inwardly angled, the vertical stacking is aligned substantially parallel to the body walls. Optionally, a dome 240 is configured at the top of the collector.Fig. 3 shows an illustration of another embodiment of a collector 300. A concentrator 320 provided in the body 310 of the collector 300 is configured to be movably guided to maximize focusing of sunlight onto the photocells. The collector 300 is erected such that one of its ends defines a base end 305 and another defines a top end 315. The top end 315 defines an opening through which light enters the collector 300. The opening may be provided with a dome structure 330 that can provide protection to the assembled components and also optionally to improve dispersion of incident light in a direction B of the reflective surface(s), the concentrator and / or the photocells. A cleaning member 340 may be provided on the dome 330 and may be used to clean the dome 330, optionally in an automated manner. The cleaning member may be arcuate such that it substantially encircles the entire external surface of the dome.The base end 305 is provided or mounted with a movable concentrator 330, which may be conical, as depicted in the figure, or may be pyramidal shaped. In the embodiment depicted in Fig. 3 and separately in Fig. 4, a conical concentrator is utilized which has a slant angle D that is selected to effectively focus incident light onto one or more regions of the photocells. In some configurations, the slant angle D may be selected such that the height of the concentrator H is at least one half of the height of a top-end of the highest H1 photocell mounted in the collector. As discussed, the slant angle and height may be determined according to the shape of the body and the presence or absence of lateral open faces for permitting sunlight therethrough. Irrespective of the concentrator height H, the concentrator 200 may have an external surface (namely the surface that is to focus or reflect the solar radiation) that is continuous or that is formed of a plurality of independent elements, wherein each of the independent elements may be individually addressable. A reflective surface(s) may be provided between arrays of the photocells, e.g., on opposing or alternating internal walls of the collector, or within the open faces of the collector (in the embodiment of FIG. 1) and / or provided as an independent array that is laterally distributed, e.g., at a top part 350 of the collector.A conical concentrator 400 is depicted in Fig. 4. Concentrator 400 includes base 405, tip 420, and slant height 410. The concentrator may be mounted on a movable surface or a lift (not shown) such that at least one of its positional vectors may be varied. Movement of the concentrator may allow to move the concentrator 400 along any axis of the body, i.e., along the x-axis and y-axis (changing the concentrator position relative to the center of the body), the z-axis (changing the distance measured from the internal base 405 to the concentrator tip) and angular rotation (changing the relative angle between the photocells and internal photocells, on one hand, and reflecting bodies of the concentrator 400, on the other). When the angular rotation is varied, an axis H extending from the base 405 of the concentrator to its tip 420 is not perpendicular to the collector’s base but rather is tilted in a direction of the reflecting surfaces or the photocells.As is apparent from the above description herein, FIGS. 1-4 illustrate different embodiments, with minor variations therebetween. Unless explicitly stated herein, components of each embodiment may be integrated with components of other embodiments. Thus, for example, the concentrator of FIG. 4 may be incorporated into any of the configurations of solar collectors of FIGS. 1-3. Likewise, the tilt angles depicted in FIGS. 2 and 3 may be utilized in a solar collector having the general structure as depicted in FIG. 1, or vice versa. Other combinations and variations may be implemented, as may be recognized by those of skill in the art. In addition to the photocells and concentrator and other structural components as described above, the collector includes components for storing and converting energy. An energy storage system, such as batteries, may be integrated to store excess energy for use during low sunlight conditions. A power conversion system may be integrated to convert the direct current (DC) electricity generated by the photocells into alternating current (AC), suitable for common electrical applications. The collector may also have a distribution system to transmit the generated electricity to desired locations or an electrical grid. Experimental ResultsA simulated experiment was performed comparing the energy generated by the solar collector illustrated in FIG. 1 and a conventional photovoltaic field. In the simulated photovoltaic field, 20 solar panels were arranged at an angle 30° to planar, facing south. This is the standard orientation for photocells in the region in which the experiment was conducted. In the simulated solar energy collector, 20 photocells were arranged in faces of 5 panels each, in the manner illustrated in FIG. 1, with an angle of 89° to planar in the directions north, south, east, and west.The simulation was performed using the PVsyst simulation tool, version 7.4. This tool is considered to be the industry standard for planning and simulating expected outputs of photovoltaic systems. The panels simulated were SolarSpace, SSA-66HD-620N. The inverter simulated was Hoymiles, HMS-2000-4T. The simulated panels were bifacial, with the concentrator not being movable.Table 1 illustrates the results of the simulation.   Table 1 - Comparison of Simulated Data for Tower with Simulated Conventional Photovoltaic Systems Tower simulationStandard setup simulationDeltaEnergy yield per system (MWh / year)10.6022.040.48System footprint (m2)9.0054.000.17Energy per SQM (MWh / year)1.180.412.89 In addition, a prototype of the solar energy collector was built, according to the specifications described above, and energetic data was gathered. The prototype of the tower outperformed the simulated tower.Table 2 illustrates a comparison of the empirical data with the simulated data from the conventional photovoltaic field. Table 2- Comparison of Empirical Data for Tower with Simulated Conventional Photovoltaic Systems  Tower empirical testingStandard setup simulationDeltaEnergy yield per system (MWh / year)12.7222.040.58System footprint m29.0054.000.17Energy per SQM (MWh / year)1.410.413.46 One reason that the simulation underestimated the energetic performance of the tower is that the simulation is somewhat complex in examination of the generated energy within the tower in comparison to standard setup in the solar field, due to shade effects.As can be seen, while the “traditional” photovoltaic field provided approximately twice the energy yield for the same number of panels, this larger energy yield came at a cost of requiring six times the surface area. Plainly, the tower configuration is highly advantageous, especially in locations in which space is limited.FIG. 5 graphically illustrates the difference in a trend of energy collection over a period of time (e.g., a day) in a classic array of photocells versus the same surface area of photocells arranged in a solar energy collector of the present disclosure. Curve 501 represents the energy obtained by the classic array of photocells. The energy curve follows a classic Gaussian distribution, with a peak registered at the time when the sun has the highest degree of incidence on the solar panels. Curve 502 illustrates the energy curve that is obtained from the solar energy collector according to the present disclosure. The harvested energy quickly rises to range 503 at the start of the day, due to the reflection and capture of sunlight at low angles, as discussed. The harvested energy stays within this range 503 throughout the day. While the maximum harvested energy is lower than the peak exhibited in curve 501, the overall daily energy harvest is significantly higher.

Claims

1. A solar energy collector for converting solar energy to electricity, the collector comprising:a hollow body having an internal structure of a truncated pyramid or conical frustum; a plurality of substantially vertically stacked photocells arranged on two or more faces of the internal structure; a concentrator having a conical or a pyramidal shape with a predetermined slant or tip angle; and a plurality of reflecting surfaces.  2. The solar energy collector of claim 1, wherein the concentrator is configured for dynamic movement and angle adjustment relative to the body.  3. The collector according to claim 12, wherein the internal structure is a polygonal structure having a number of walls between 2 and 16.  4. The collector according to claim 3, wherein photocells are mounted on alternating faces of the body.   5. The collector according to claim 4, wherein the faces of the body not having photocells are at least partially open and allow sunlight therethrough.  6. The collector according to claim 5, wherein one or more reflecting surfaces, oriented toward an interior of the hollow body, is arranged within one or more of the at least partially open faces.   7. The collector according to claim 1, wherein the photocells are inwardly tilted to an internal angle between 70 and 89.9⁰.  8. The collector according to claim 1, wherein each of the photocells comprises a photoemissive surface, a photovoltaic surface, or a photoconductive surface.   9. The collector according to claim 1, wherein the photocells are bifacial.  10. The collector according to claim 9, wherein each of the bifacial photocells comprises a more efficient face and a less efficient face, and wherein the more efficient face is oriented toward an outside of the body, and the less efficient face is oriented toward an inside of the body.   11. The collector according to claim 1, wherein each of the photocells is static or is individually addressable so that the photocell orientation or angle with respect to the concentrator may be adjusted.   12. The collector according to claim 1, wherein the photocells are grouped based on their type or based on their position in the collector.   13. The collector according to claim 1, wherein movement of the concentrator is governed by a sun tracking system configured and operable to automate an adjustment of the concentrator.  14. The collector according to claim 13, wherein movement of the concentrator is programmed based on one or more of a location of the collector, a height of the collector, and a season or time of year.  15. The collector according to claim 1, provided with an energy storage system, or provided with at least one sensor and a monitoring system to track proper performance of the photocells, the concentrator movement, and environmental conditions, or provided with a control system configured and operable to manage automated adjustments of the photocells and the concentrator for optimal operational efficiency.   16. The collector according to claim 1 provided with a dome structure.   17. The collector according to claim 16, wherein the dome is provided with an automated cleaning member.   18. A solar field or a solar array provided with a plurality of solar collectors according to claim 1.   19. A movable concentrator having a continuous light reflective surface or a reflective surface formed of a plurality of reflective members, wherein one or more of the plurality of the reflective members are addressable, individually or as a group, to maximize light incidence onto the reflective members; the concentrator having a base provided with a means for moving the concentrator vertically or laterally and / or for adjusting its angle with respect to its base, and wherein the concentrator is conical or pyramidal in shape.  20. The concentrator according to claim 19, configured for assembly or use in a solar tower or a solar light collector. 

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