ARCHITECTURAL ARTICLE WITH PHOTOVOLTAIC CELL AND VISIBLE LIGHT-TRANSMITTING REFLECTOR

• US 20140083482A1
• Filed: 05/09/2012
• Published: 03/27/2014
• Est. Priority Date: 05/09/2011
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Hebrink, Timothy J.
• Application Number:
  US14/116,674
• Publication Number:
  US 20140083482A1
• Time in Patent Office: Days
• US Class Current: 136/246
• CPC Class Codes: B32B 2250/42 Alternating layers, e.g. ABAB(C), AABBAABB(C)
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2307/418 Refractive
• CPC Class Codes: B32B 2307/71 Resistive to light or to UV
• CPC Class Codes: B32B 2419/00 Buildings or parts thereof walls, panels B32B2607/00
• CPC Class Codes: B32B 2419/06 Roofs, roof membranes
• CPC Class Codes: B32B 2457/12 Photovoltaic modules
• CPC Class Codes: B32B 27/304 comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• CPC Class Codes: B32B 27/308 comprising acrylic (co)polymers
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: B32B 7/023 Optical properties
• CPC Class Codes: G02B 5/20 Filters polarising elements G02B5/30
• CPC Class Codes: H01L 31/02325 the optical elements not being integrated nor being directly associated with the device
• CPC Class Codes: H01L 31/054 Optical elements directly associated or integrated with the PV cell, e.g. light-reflecting means or light-concentrating means
• CPC Class Codes: H02S 40/22 Light-reflecting or light-concentrating means directly associated with the PV cell or integrated with the PV cell H01L31/054
• CPC Class Codes: Y02E 10/52 PV systems with concentrators

Abstract

An architectural article that includes a photovoltaic cell and a visible light-transmitting reflector positioned to reflect light onto the photovoltaic cell is disclosed. The visible light-transmitting reflector includes a multilayer optical film having an optical stack with a plurality of alternating first and second optical layers having different indices of refraction. The multilayer optical film reflects at least a portion of light in a range of wavelengths that corresponds with the absorption bandwidth of the photovoltaic cell.

Claims

1. An architectural article comprising:

a photovoltaic cell having an absorption bandwidth; and

a visible light-transmitting reflector positioned to reflect light onto the photovoltaic cell, the visible light-transmitting reflector comprising a multilayer optical film having an optical stack comprising a plurality of alternating first and second optical layers with different indices of refraction, wherein the multilayer optical film reflects at least a portion of light in a range of wavelengths that corresponds with the absorption bandwidth of the photovoltaic cell.

2. The architectural article of claim 1, wherein the architectural article is installed as part of a building and allows visible light to enter the building through the visible light-transmitting reflector.

3. The architectural article of claim 1, wherein the visible light-transmitting reflector has an average visible light transmission of at least 30 percent.

4. The architectural article of claim 1, wherein the multilayer optical film is a color-shifting film having a left band edge in a range from 600 to 750 nanometers.

5. The architectural article of claim 1, wherein the multilayer optical film has an average light reflection of at least 50 percent at a normal angle to the multilayer optical film in a wavelength range selected from the group consisting of 650 nanometers to 1100 nanometers, 650 nanometers to 1500 nanometers, 875 nanometers to 1100 nanometers, and 875 nanometers to 1500 nanometers.

6. The architectural article of claim 1, further comprising an ultraviolet light protective layer on at least one surface of the visible light-transmitting reflector.

7. The architectural article of claim 6, wherein the ultraviolet light protective layer comprises poly(vinylidene difluoride), poly(methyl methacrylate), and an ultraviolet light absorber.

8. The architectural article of claim 6, wherein the ultraviolet light protective layer is a multilayer ultraviolet light reflective mirror.

9. The architectural article of claim 1, further comprising a visible light-transmitting substrate to which at least the multilayer optical film is applied.

10. The architectural article of claim 1, wherein the multilayer optical film is formed into multiple reflective surfaces that reflect onto multiple photovoltaic cells.

11. The architectural article of claim 1, wherein the multilayer optical film is present in multiple parallel ridges separated by multiple land areas, wherein multiple photovoltaic cells are located in the multiple land areas.

12. The architectural article of claim 1, further comprising multiple parallel ridges each having first and second opposing ridge faces, wherein the visible light-transmitting reflector is located on each first ridge face, and wherein the photovoltaic cell is located on each second ridge face.

13. The architectural article of claim 1, further comprising at least one of an anti-soiling or a scratch-resistant coating on at least one surface of the visible light-transmitting reflector.

14. The architectural article of claim 1, wherein the power output of the photovoltaic cell is increased by at least 25 percent in comparison to an equivalent photovoltaic cell in the absence of any concentrating mirrors.

15. The architectural article of claim 1, wherein the photovoltaic cell is a crystalline silicon single junction cell, a ribbon silicon cell, a copper indium gallium selenide cell, or a gallium arsenide cell.

16. The architectural article of claim 1, wherein the architectural article forms at least a portion of a window, a skylight, a door, a roof, an awning, an atrium, a door, or a combination thereof.

17. The architectural article of claim 1, wherein the architectural article forms at least a portion of a roof of a building, carport, or parking lot.

18. The architectural article of claim 1, wherein the first optical layers comprise polyethylene terephthalate, and wherein the second optical layers comprise poly(methyl methacrylate), copolymers of methyl methacrylate and other acrylate monomers, or blends of poly(methyl methacrylate) and poly(vinylidene difluoride).

19. The architectural article of claim 1, wherein the architectural article transmits at least a portion of infrared light outside the absorption bandwidth of the photovoltaic cell.

20. The architectural article of claim 1, further comprising a celestial tracking mechanism.