Window for a building or structure
The window design with luminescence and light-scattering materials on the exterior, combined with solar cells, addresses heat absorption and generates electricity efficiently, enhancing energy efficiency by downshifting wavelengths and reflecting light back to solar cells.
Patent Information
- Application Number
- JP2024575632
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-06-21
- Filing Date
- 2023-06-21
- Publication Date
- 2025-07-03
AI Technical Summary
Existing windows in buildings absorb a significant amount of sunlight, leading to increased heating and high energy consumption for air conditioning, despite technologies like spectral selective panels generating electricity from infrared radiation.
A window design featuring a luminescence material and light-scattering material on the exterior surface, with solar cells along the edge, absorbing fluorescent emissions and scattered light to generate electricity, while maintaining transparency and reducing heat absorption.
The design enhances electricity generation and reduces heat absorption, improving energy efficiency by utilizing luminescence materials to downshift wavelengths and reflect unabsorbed light back to solar cells, optimizing power output and reducing cooling demands.
Smart Images
Figure 2025520731000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to windows for buildings or structures, and more particularly, but not exclusively, to windows that generate electricity.
Background Art
[0002] Buildings such as office towers, high-rise residences, and hotels use a large number of external window panels and / or facades incorporating glass panels.
[0003] Such glass panels receive a large amount of sunlight, as a result of which the interior space is heated and the use of air conditioning equipment is required. A large amount of energy is used globally for the operation of air conditioning equipment.
[0004] PCT International Application Numbers PCT / AU2012 / 000778, PCT / AU2012 / 000787, and PCT / AU2014 / 000814 (owned by the applicant) disclose spectral selective panels that can be used as window glass and are transparent to visible light but absorb light such as infrared and / or other re-emitted (internal wavelength-converted) radiation to generate electricity, with solar cell modules attached thereto.
[0005] The present invention provides further improvements.
Summary of the Invention
[0006] In a first aspect, the present invention is a window for a building or structure, a first panel that is at least mostly transparent to visible light and has opposing first and second major surfaces, the first major surface being a light-receiving surface, the first panel including a luminescence material and / or a light-scattering material, a plurality of solar cells facing the second major surface of the first panel and arranged along and proximate to an edge of the first panel, and a frame that directly or indirectly supports the first panel. The first main surface of the first panel is directly exposed to the space outside the window. A window is provided.
[0007] The first panel of the window is arranged such that light emitted from outside the building or structure is received by the light-receiving surface of the first panel before passing through other parts of the window.
[0008] A plurality of solar cells may face directly the second main surface of the first panel. The solar cells may be parallel to the second surface or may be arranged at an inclined orientation with respect to the second main surface.
[0009] In one embodiment, the first panel comprises parallel first panel portion and second panel portion, which may be laminated together.
[0010] The first main surface may be the surface of the first panel portion, and the second main surface may be the surface of the second panel portion. The first panel portion and the second panel portion can be laminated together using a sandwich layer containing ethylene vinyl acetate (EVA) or other suitable materials.
[0011] The luminescence material may be embedded in the sandwich layer. The sandwich layer can include polyvinyl butyral (PVB). In a specific example, the luminescence material may be embedded in PVB and may include an inorganic luminophore material.
[0012] The fluorescent emission emitted by the luminescence material is directed in random directions, and a part of the emitted fluorescent emission is directed towards the end of the first panel (e.g., by total internal reflection within the first panel or by reflection on other surfaces of the window), where a part of the light can be absorbed by the solar cell for power generation. Since the first panel faces directly the space outside the window, the luminescence material is arranged near the outside of the window, thereby avoiding the intensity loss that would otherwise be experienced when the incident light passes through a plurality of panels such as glass panels before reaching the luminescence material.
[0013] The end of the first panel may be a polished end and may be provided with a reflective coating such as a metal coating. The reflective coating at the end of the first panel reflects the unabsorbed light back towards the solar cell, promoting absorption.
[0014] Also, since the fluorescent emission has a longer wavelength than the light absorbed by the luminescence material, the luminescence material can effectively downshift the wavelength of the incident light. The incident light is absorbed by the luminescence material and then the fluorescent emission is emitted in random directions including the direction in which the fluorescent emission is guided through the first panel. For example, the luminescence material can be configured to convert incident light in a wavelength range where the solar cell has a relatively low external quantum efficiency (EQE) into fluorescent emission in a wavelength range with a higher EQE.
[0015] The solar cell may be arranged between a part of the frame and the first panel in the vicinity of the end of the first panel. The solar cell may cover a part of the frame structure.
[0016] The solar cell may be spaced apart from the first panel or may be in contact with the first panel. The solar cell may be arranged parallel to the second main surface of the first panel and may directly face the second main surface of the first panel. Alternatively, the solar cell may be arranged at an angle with respect to the second main surface of the first panel. For example, the solar cell can be tilted at an angle less than 90°, less than 70°, less than 50°, less than 30°, or less than 10°.
[0017] The plurality of solar cells may include a first series of solar cells, and the window may include a second series of solar cells. The second series of solar cells may be arranged along the first series of solar cells or may be arranged adjacent to the first series of solar cells. The second series of solar cells may have the same orientation as the first series of solar cells or may not have the same orientation. The second series of solar cells may be arranged parallel to the second main surface of the first panel or may directly face the second main surface. Alternatively, the second series of solar cells may be arranged at an angle with respect to the second main surface of the first panel. For example, the second series of solar cells can be tilted at an angle less than 90°, less than 70°, less than 50°, less than 30°, or less than 10°.
[0018] In a specific embodiment, the first series of solar cells is arranged parallel to the second main surface of the first panel and is arranged between a part of the frame and the first panel. In this embodiment, the second series of solar cells is directly adjacent to the first series of solar cells and is arranged at an angle with respect to the first panel. These tilted solar cell modules will face the internal space of the window in substantially four different geometric orientations with respect to the incident sunlight. Therefore, when the sun moves across the sky, the energy recovery by the window is improved.
[0019] The first panel portion and the second panel portion may include a suitable glass or polymer material. In a specific embodiment, the first panel portion and the second panel portion include ultra-clear low-iron glass.
[0020] The window may further include a second panel disposed parallel to the first panel. The second panel may have a main surface facing a space outside the window, such as the interior space of a building or structure, when the window is attached to the building or structure. The frame and the solar cell may be disposed between the first panel and the second panel.
[0021] The second panel may also include a coating such as a low-emissivity coating that provides a high reflectivity for wavelengths in the range of about 300 nm to 420 nm, optionally about 750 nm to 1000 nm, or for even higher wavelengths. This coating can spectrally selectively reflect the emitted fluorescent radiation and the scattered incident light.
[0022] The solar cell is generally silicon-based, but alternatively can include CuInSe2, CIG or CIS, GaAs, CdS or CdTe.
[0023] The window may be configured such that the central region of the window is transparent to at least most of the visible light and is at least 5 times, 10 times, 15 times, 20 times, 50 times, 100 times, or even 500 times larger than the region of the panel where a series of solar cells are disposed.
[0024] The central region that is transparent to at least most of the visible light may have a transmittance of at least 60%, 70%, 80%, 90%, or at least 95%, or may be transparent to the visible light that normally incident on the light-receiving surface at normal incidence.
[0025] The present invention will be more fully understood from the following description of specific embodiments of the invention. Hereinafter, it will be described with reference to the accompanying drawings.
Brief Description of the Drawings
[0026]
Figure 1
Figure 2
Modes for Carrying Out the Invention
[0027] First, referring to FIG. 1, a schematic top view of a window 100 according to an embodiment of the present invention is shown. The window 100 includes a first panel 102 and a first series of four solar cells 104, 106, 108, 110 disposed proximate to each end of the first panel 102. The first series of four solar cells 104, 106, 108, 110 directly face the light-receiving surface of the first panel 102 and together surround a region of the panel that is at least mostly light-transmissive. The window 100 also includes a second series of four solar cells 112, 114, 116, and 118. The first series of solar cells 104, 106, 108, 110 are arranged parallel to the first panel 102 in this embodiment, and the second series of solar cells 112, 114, 116, and 118 are arranged inclined with respect to the first panel 102. The window 100 also includes a frame structure disposed behind the first series of solar cells 104, 106, 108, 110. The frame structure directly or indirectly supports the first panel. Further, the window 100 includes a second panel (not shown) facing the first panel 102 and arranged parallel to the first panel 102, and the second panel is exposed to the internal space of the building or structure to which the window 100 is attached during use.
[0028] The first panel 102 is transparent to at least 90% of the incident visible light. The first series of solar cells 104, 106, 108, 110 and the second series of solar cells 112, 114, 116, and 118 are arranged only in the end regions of the first panel 102 such that the transmission of the incident light is blocked by the solar cells only in the end regions of the first panel 102.
[0029] Referring now to FIG. 2, window 100 will be described in more detail. Like features are given like reference numerals. Each of the first series of solar cells 108 and the second series of solar cells 116 is supported by a frame 200. FIG. 2 also shows a second panel 202 of the window 100.
[0030] The first panel 102 has a first major surface 210 that is exposed to the space outside the window 100, and this first major surface 210 is the surface that receives direct sunlight originating from outside the building or structure when the window is attached to the building or structure.
[0031] The first panel 102 comprises parallel first panel portions 204 and second panel portions 206, and the first panel portions 204 and second panel portions 206 are bonded to each other using a sandwich layer in the form of a polyvinyl butyral (PVB) layer 208. In the present embodiment, the panel portions 204, 206 are ultra-clear low-iron glass sheets having a thickness of 4 mm, and the PVB layer 208 has a thickness of 0.76 mm or 1.52 mm in the present embodiment.
[0032] In the present embodiment, the window 100 further includes a luminescence material embedded in the PVB layer 208. In a variant of the described embodiment, the PVB layer 208 also includes two component layers, and each of the two component layers may include a respective luminescence material and / or a respective luminescence material concentration.
[0033] The luminescent material within the PVB layer 208 absorbs incident light and emits fluorescent radiation in random directions. A portion of the emitted fluorescent radiation is directed into the first panel 102 by total internal reflection towards the end region of the first panel 102, and a portion of the light can be absorbed by solar cells (such as the solar cells in series 108, 116) for power generation. Since the first panel 102 directly faces the space outside the window, the luminescent material is disposed near the outside of the window (the thickness of the panel portion 206 is only 4 mm), thereby avoiding the intensity loss that would be experienced in this arrangement when the incident light passes through multiple panels such as multiple glass panels before reaching the luminescent material.
[0034] The first panel 102 further includes a reflective coating 220 at its end, such as a coating formed from a paint / spray containing a metallic material or reflective particles. The reflective coating 220 is located on the polished end of the first panel 102 (~90-degree cut). The reflective coating 220 facilitates reflecting the light not absorbed by the solar cells back towards the solar cells for absorption.
[0035] The luminescent material also effectively downshifts the wavelength of a portion of the incident light. For example, the luminescent material can be arranged to convert incident light in a wavelength range where the solar cells have a relatively low external quantum efficiency (EQE) (e.g., 300 nm - 490 nm for silicon-based solar cells) into fluorescent radiation in a higher EQE range (~800 - 1000 nm, and / or ~600 - 800 nm).
[0036] In the described embodiment, the solar cells of a series of solar cells (such as series 108, 116) are disposed between a portion of the frame 200 and the first panel 102 in the end region of the first panel 102. The solar cells cover most of the frame 200 when viewed through the first panel 102.
[0037] In this embodiment, the first series of solar cells (104, 106, 108, and 110) and the second series of solar cells (112, 114, 116, and 118) are spaced apart from the first panel 102. The second series of solar cells 112, 114, 116, and 118 are arranged parallel to the first panel 102. The first series of solar cells 104, 106, 108, and 110 are arranged inclined with respect to the first panel 102. In this embodiment, the first series of solar cells 104, 106, 108, and 110 are arranged at an angle of 30° with respect to the first panel 102.
[0038] Since the first series of solar cells 104, 106, 108, and 110 are arranged inclined with respect to the first panel 102, these solar cells receive both sunlight from the incident direction and light scattered or reflected at the surfaces or interfaces within the window 100. Also, the inclined solar cells of the first series 104, 106, 108, and 110 are less likely to be geometrically in a directly light-shielding position when the framed window is exposed to sunlight, thereby making it easier to improve the uniformity of the irradiation intensity among the first series of solar cells 104, 106, 108, and 110, which improves the power output of the window 100.
[0039] The second panel 202 also includes a low-emissivity coating 222. The low-emissivity coating 222 enables spectrally selective reflection of incident sunlight, emitted fluorescence radiation, and scattered incident light. In this embodiment, the low-emissivity coating 222 is arranged to have a high reflectivity for wavelengths between 300 and about 420 nm and also a high reflectivity for wavelengths between about 750 and about 1000 nm.
[0040] One skilled in the art will understand that in alternative embodiments, the first series of solar cells 104, 106, 108, and 110 may be tilted at another suitable angle. Further, the second series of solar cells 112, 114, 116, and 118 may alternatively be arranged at an angle inclined with respect to the first panel 102. Further, in another alternative embodiment, the window 100 may not include the first series of solar cells 104, 106, 108, and 110. One skilled in the art will also understand that the provided dimensions are merely exemplary and that various other dimensions are within the scope of the embodiments of the present invention.
[0041] Any discussion of background art throughout this specification should not be considered as an admission that such background art is prior art, nor should it be considered as an admission that such background art is widely known or forms part of the common general knowledge in the field in Australia or the world.
Claims
1. A window for a building or a structure, comprising a first panel that is at least mostly transmissive to visible light and has opposing first and second major surfaces, wherein the first major surface is a light-receiving surface, and the first panel includes a luminescence material and / or a light-scattering material; a plurality of solar cells facing the second major surface of the first panel and arranged along and in proximity to an edge of the first panel; a frame that directly or indirectly supports the first panel; wherein the first major surface of the first panel is directly exposed to a space outside the window. Window
2. The window according to claim 1, wherein the plurality of solar cells directly face the second major surface of the first panel.
3. The window according to claim 1 or 2, wherein the first panel is arranged such that light emitted from outside the building or structure is received by the light-receiving surface of the first panel before passing through other portions of the window.
4. The window according to any one of claims 1 to 3, wherein the first panel comprises parallel first and second panel portions bonded to each other, the first major surface is the surface of the first panel portion, and the second major surface is the surface of the second panel portion.
5. The window according to claim 4, wherein the first panel portion and the second panel portion are bonded to each other using a sandwich layer containing polyvinyl butyral (PVB).
6. The window according to any one of claims 1 to 5, wherein the first panel includes the luminescence material.
7. The window according to claim 6, wherein the luminescence material is configured to convert incident light in a wavelength range in which the solar cell has a relatively low external quantum efficiency (EQE) into fluorescent radiation in a wavelength range with a higher EQE.
8. The window according to claim 6 or claim 7, which depends on claim 5, wherein the luminescence material is embedded in the PVB.
9. The window according to any one of claims 1 to 8, wherein an edge of the first panel is provided with a reflective coating including a metal coating.
10. The solar cell is disposed between a part of the frame and the first panel in the vicinity of an end of the first panel, the window according to any one of claims 1 to 9.
11. The solar cell covers a part of the structure of the frame, the window according to any one of claims 1 to 10.
12. The solar cell is spaced apart from the first panel, the window according to any one of claims 1 to 11.
13. The solar cell is disposed parallel to the second main surface of the first panel and directly faces the second main surface of the first panel, the window according to any one of claims 1 to 12.
14. The solar cell is disposed at an angle with respect to the second main surface of the first panel, the window according to any one of claims 1 to 13.
15. The plurality of solar cells includes a first series of solar cells, the window includes a second series of solar cells, the second series of solar cells is disposed along and adjacent to the first series of solar cells, the window according to any one of claims 1 to 14.
16. The second series of solar cells has the same orientation as the first series of solar cells, is disposed parallel to the second main surface of the first panel, and directly faces the second main surface of the first panel, the window according to claim 15.
17. The second series of solar cells does not have the same orientation as the first series of solar cells and is disposed at an angle with respect to the second main surface of the first panel, the window according to claim 15 or claim 16.
18. The first series of solar cells is disposed parallel to the second main surface of the first panel and is disposed between a part of the frame and the first panel, the second series of solar cells is directly adjacent to the first series of solar cells and is disposed at an angle with respect to the first panel, the window according to claim 17.
19. The window further includes a second panel disposed parallel to the first panel, the window according to any one of claims 1 to 18.
20. The window according to claim 19, wherein the second panel comprises a coating including a low-emissivity coating that provides high reflectivity for wavelengths of 300 nm to about 420 nm, typically about 750 nm to about 1000 nm, and / or higher. **Claim 21** The window according to claim 19 or claim 20, wherein the frame and the solar cell are disposed between the first panel and the second panel.