Patterned glass cylindrical lens arrays for concentrated photovoltaic systems, and/or methods of making the same

• US 9,423,533 B2
• Filed: 04/26/2010
• Issued: 08/23/2016
• Est. Priority Date: 04/26/2010
• Status: Active Grant

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Krasnov, Alexey, den Boer, Willem
• Primary Examiner(s): LUU, THANH X
• Application Number:
  US12/662,624
• Publication Number:
  US 20110259394A1
• Time in Patent Office: 2,311 Days
• Field of Search: 136/246, 250/203.4
• US Class Current: 1/1
• CPC Class Codes: C03B 18/14 Changing the surface of the glass ribbon, e.g. roughening by chemical methods C03C
• CPC Class Codes: F24S 23/31 having discontinuous faces, e.g. Fresnel lenses
• CPC Class Codes: G02B 3/005 arranged along a single direction only, e.g. lenticular sheets G02B3/0043 takes precedence
• CPC Class Codes: G02B 3/0056 arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: G02B 3/0062 Stacked lens arrays, i.e. refractive surfaces arranged in at least two planes, without structurally separate optical elements in-between
• CPC Class Codes: H01L 31/0521 using a gaseous or a liquid coolant, e.g. air flow ventilation, water circulation
• CPC Class Codes: H01L 31/0543 comprising light concentrating means of the refractive type, e.g. lenses
• CPC Class Codes: H01L 31/0547 comprising light concentrating means of the reflecting type, e.g. parabolic mirrors, concentrators using total internal reflection
• CPC Class Codes: Y02B 10/20 Solar thermal
• CPC Class Codes: Y02E 10/52 PV systems with concentrators

Abstract

Certain example embodiments of this invention relate to patterned glass that can be used as a cylindrical lens array in a concentrated photovoltaic application, and/or methods of making the same. In certain example embodiments, the lens arrays may be used in combination with strip solar cells and/or single-axis tracking systems. That is, in certain example embodiments, lenses in the lens array may be arranged so as to concentrate incident light onto respective strip solar cells, and the entire assembly may be connected to a single-axis tracking system that is programmed to follow the East-West movement of the sun. A low-iron glass may be used in connection with certain example embodiments. Such techniques may advantageously help to reduce cost per watt related, in part, to the potentially reduced amount of semiconductor material to be used for such example embodiments.

Claims

1. A photovoltaic system, comprising:

a plurality of elongated solar cells, each said solar cell comprising c-Si;

tubing through which liquid flows, the tubing located proximate the solar cells;

a plurality of lenses oriented along a common axis, each said lens being configured to concentrate incident light in substantially one dimension so that the lenses concentrate light toward the elongate solar cells and toward the tubing in order to heat the liquid in the tubing, each said lens having a concentration ratio of 3×

-30×

, wherein said elongate solar cells are spaced apart from each other so that adjacent solar cells are not in direct contact with each other;

wherein said lenses are formed from patterned soda-lime-silica glass having a low iron content, the soda-lime silica glass forming the lenses containing from 0.01 to 0.08% total iron and a glass redox of no greater than 0.08;

wherein said lenses comprise first and second sub-lens arrays, each sub-lens array comprising plano-convex lenses, the first and second sub-lens arrays being laminated to one another via laminating material comprising PVB such that the planar sides of the first and second sub-lens arrays are adjacent to one another;

wherein the lenses are spaced apart from corresponding solar cells toward which they concentrate incident light, and wherein each of said lenses has a convex top surface and a convex bottom surface when viewed in cross section so that an apex of the convex bottom surface of each lens is centered over and spaced apart from the corresponding solar cell, toward which it concentrates incident light; and

wherein an elongated axis of each said solar cell is substantially aligned with and substantially parallel to an elongated axis of a corresponding branch of said tubing, so that said branches of said tubing extend in substantially the same direction as the overlying solar cells.

2. The system of claim 1, wherein

each said c-Si solar cell is at least about 20% efficient.

3. The system of claim 1, wherein

each said lens has a focal length of about 20-200 mm.

4. The system of claim 1, wherein

each said lens has a width of about 10-100 mm, a minimum thickness of about 2-4 mm, and a maximum thickness of about 4-8 mm.

5. The system of claim 1, wherein

each said lens has a focal length of about 20-200 mm, and wherein

each said lens has a width of about 10-100 mm, a minimum thickness of about 2-4 mm, and a maximum thickness of about 4-8 mm.

6. The system of claim 1, wherein

each said lens is a plano-convex lens.

7. The system of claim 1, further comprising

a single-axis tracking system, the single-axis tracking system being configured to move the lenses and/or the plurality of elongate solar cells so as to substantially match the East-West movement of the sun.

8. The system of claim 1, wherein

the solar cells are formed using chip on glass manufacturing techniques and are connected to one another using interconnecting wires and/or copper tape.

9. The system of claim 1, further comprising

an antireflective coating wet-applied to the lenses.

10. The system of claim 9, wherein the antireflective coating comprises silicon oxide having an index of refraction of about 1.3.

11. The system of claim 1, wherein

the liquid comprises water.

12. The system of claim 1, wherein

the liquid is a cooling liquid for cooling the solar cells when entering the tubing, and is heated when exiting the tubing.

13. A photovoltaic system, comprising:

a plurality of elongated photovoltaic cells;

tubing through which liquid flows, the tubing located proximate the photovoltaic cells;

a plurality of lenses oriented along a common axis, each said lens being configured to concentrate incident light in substantially one dimension so that the lenses concentrate light toward the elongate photovoltaic cells and toward the tubing in order to heat the liquid in the tubing, wherein said elongate photovoltaic cells are spaced apart from each other so that adjacent photovoltaic cells are not in direct contact with each other;

wherein said lenses are formed from patterned soda-lime-silica glass having a low iron content, the soda-lime silica glass forming the lenses containing from 0.01 to 0.08% total iron and a glass redox of no greater than 0.08;

wherein said lenses comprise first and second sub-lens arrays, each sub-lens array comprising plano-convex lenses, the first and second sub-lens arrays being laminated to one another via laminating material comprising PVB such that the planar sides of the first and second sub-lens arrays are adjacent to one another;

wherein the lenses are spaced apart from corresponding photovoltaic cells toward which they concentrate incident light, and wherein each of said lenses has a convex top surface and a convex bottom surface so that an apex of the convex bottom surface of each lens is centered over and spaced apart from the corresponding photovoltaic cell, toward which it concentrates incident light; and

wherein an elongated axis of each said solar cell is substantially aligned with and substantially parallel to an elongated axis of a corresponding branch of said tubing, so that said branches of said tubing extend in substantially the same direction as the overlying solar cells.

14. The system of claim 13, wherein

each said lens has a focal length of about 20-200 mm.

15. The system of claim 13, wherein

each said lens has a width of about 10-100 mm, a minimum thickness of about 2-4 mm, and a maximum thickness of about 4-8 mm.

16. The system of claim 13, further comprising

a single-axis tracking system, the single-axis tracking system being configured to move the lenses and/or the plurality of elongate photovoltaic cells so as to substantially match the East-West movement of the sun.

17. The system of claim 13, wherein

the photovoltaic cells are formed using chip on glass manufacturing techniques and are connected to one another using interconnecting wires and/or copper tape.

18. The system of claim 13, further comprising

an antireflective coating wet-applied to the lenses.