JP5015889B2 - Solar cell panel and solar power generation device - Google Patents

Description

  The present invention relates to a solar cell panel and a solar power generation device.

  FIG. 19 is a graph showing an outline of the relationship between the luminous flux density of incident light incident on a solar battery cell and the electromotive force of the solar battery cell. “Flux density” in FIG. 19 means the amount of light per unit area received by the solar battery cell. FIG. 20 is a schematic diagram for explaining the time during which power generation can be performed using the sun moving daily as a light source.

  As shown in FIG. 19, when the luminous flux density is below the threshold value TH, the electromotive force of the solar battery cell is extremely small. However, when the luminous flux density is above the threshold value TH, the electromotive force of the solar battery cell is equal to the luminous flux density. Rise in proportion to the rise. However, when the luminous flux density reaches the saturation level ST, the electromotive force of the solar battery cell is saturated and the increase is slow.

  Therefore, as shown in FIG. 20, when the solar cells are installed in the direction of the sun 932 at the time of south and middle, from the suns 934 and 936 at a low position in the time zone after sunrise and before sunset, to the solar cells. The incident angle of sunlight increases. When the incident angle increases, the light flux density of sunlight received by the solar battery cell is lower than the threshold value TH. Moreover, since strong surface reflection arises with respect to the incident sunlight, the light which reaches a photovoltaic cell decreases. For this reason, when the sun is at a low position in the time zone after sunrise and before sunset, it is substantially impossible to generate power.

  Patent Document 1 is a prior art document in which a document known invention related to the present invention is described. In Patent Document 1, the light receiving surface of the solar battery cell is covered with a transparent body in which prisms are densely arranged on the side facing the light receiving surface of the solar battery cell and lenses are densely arranged on the side not facing the light receiving surface of the solar battery cell. A solar cell panel is disclosed.

JP 2005-285948 A

  However, the solar cell panel of Patent Document 1 increases the efficiency of power generation when the sun is at a low position with an incident angle of about 60 degrees, but when the incident angle is larger, the lens and the prism interfere with the incident light. Therefore, the efficiency of power generation when the sun is in a very low position such as morning and evening is significantly reduced. Therefore, the solar cell panel of Patent Document 1 has a limited range in which power is efficiently generated by the sun moving in a diurnal motion.

  The present invention has been made to solve this problem, and includes a solar cell panel and solar power generation that can efficiently generate power even when the morning and evening incident angles are large due to the diurnal sun. An object is to provide an apparatus.

  In order to solve the above-described problem, a solar cell panel according to claim 1 includes a solar cell and a first transparent body that covers a light-receiving surface of the solar cell, and the light-receiving surface of the first transparent body. A first group of discrete incident regions that occupy a relatively small range at a relatively large angle with the light-receiving surface of the solar battery cell on the first surface that does not face the light-receiving surface of the solar battery cell; And a flat second incident region that occupies a relatively small angle and occupies a relatively large range, and the oblique incident light incident on the first incident region is converted into a light flux density on the first transparent body. A group of micro optical elements that are led to the light receiving surface of the solar battery cell after being enlarged are discretely formed out of the second incident region.

  The solar cell panel according to claim 2 is the solar cell panel according to claim 1, wherein the minute optical element is a lens surface that collects incident oblique incident light and an incident surface incident on the incident surface. And a reflecting surface that bends in the direction of normal to the light receiving surface of the solar battery cell.

  According to a third aspect of the present invention, there is provided the solar cell panel according to the first aspect, wherein the minute optical element enters an incident surface and a traveling direction of oblique incident light incident on the incident surface and enters the light receiving surface of the solar cell. It is a microprism having a reflecting surface that bends in the line direction.

  A solar cell panel according to a fourth aspect is the microlens according to the solar cell panel according to the first aspect, wherein the minute optical element has an incident surface serving as a lens surface for collecting incident oblique incident light.

  The solar cell panel according to claim 5 is the solar cell panel according to any one of claims 1 to 4, wherein the group of the micro optical elements is a first perpendicular to the normal direction extending from the light receiving surface of the solar cell. A first group in which the incident surface faces in a direction inclined from the light-receiving direction of the solar cell toward the normal direction coming out of the light-receiving surface of the solar cell, and the first group perpendicular to the normal direction coming out of the light-receiving surface of the solar cell. A second group in which the incident surface faces a direction inclined from a second direction opposite to the direction to a normal direction extending from the light receiving surface of the solar battery cell.

  A solar cell panel according to a sixth aspect is the solar cell panel according to any one of the first to fifth aspects, wherein the groups of the micro optical elements are discretely arranged in at least one direction, and the height of the micro optical elements is It is 0.1 to 1.0 times the arrangement interval in the direction of discrete arrangement of the group of micro optical elements.

  The solar cell panel according to claim 7 is the solar cell panel according to claim 6, wherein the height of the micro optical element is 5-5000 μm, and the arrangement interval in the direction in which the groups of the micro optical elements are discretely arranged is 25-25000 μm. It is.

  The solar battery panel according to claim 8 is the solar battery panel according to any one of claims 1 to 7, wherein the solar battery cell is provided on a photoelectric conversion body that performs photoelectric conversion and a light receiving surface of the photoelectric conversion body. And a back electrode provided on a non-light-receiving surface of the photoelectric converter, the surface electrode receiving light of the solar cell to which the oblique incident light incident on the first incident region reaches. A first group of finger electrodes adjacent to the first light receiving area on the surface.

  The solar cell panel according to claim 9 is the solar cell panel according to claim 8, wherein the surface electrode is electrically separated from the group of the first finger electrodes, and vertically incident light incident on the second incident region is received. And a second group of finger electrodes provided in a second light receiving region on the light receiving surface of the solar cell that reaches.

  The solar cell panel according to claim 10 is the solar cell panel according to claim 8 or 9, wherein the surface electrode is embedded in a groove formed in the photoelectric converter, and the light receiving surface of the solar cell of the surface electrode. And the portion other than the portion where the groove is formed on the light receiving surface of the photoelectric converter form the same plane.

  The solar cell panel according to claim 11 is the solar cell panel according to any one of claims 8 to 10, wherein the surface electrode is a film of a transparent conductive material.

  The solar cell panel according to claim 12 is the solar cell panel according to any one of claims 1 to 11, wherein the solar cell panel covers the first surface of the first transparent body and the first surface of the first transparent body. The second surface is further provided with a second transparent body having a flat third surface that does not face and having a refractive index smaller than that of the first transparent body.

  The solar cell panel according to claim 13 is the solar cell panel according to claim 12, wherein the second surface of the first transparent body facing the light receiving surface of the solar cell is in close contact with the light receiving surface of the solar cell. is doing.

  The solar power generation device according to claim 14 includes a solar cell panel having a plurality of current collection paths having different power output dependencies with respect to an incident angle of incident light, and a dominant current collection path among the plurality of current collection paths. And a current collecting circuit for selectively collecting current from.

  According to the first aspect of the present invention, the oblique incident light is guided to the light receiving surface of the solar battery cell after the luminous flux density is increased, and the normal incident light and the substantially vertical incident light are guided almost directly to the light receiving surface of the solar battery cell. Therefore, light having a sufficient light flux density reaches the light receiving surface of the solar battery cell regardless of whether oblique incident light, vertical incident light, or substantially vertical incident light is incident. Thereby, it is possible to generate power efficiently by the sun moving in a diurnal motion.

  According to the invention of claim 2, since the oblique incident light is condensed and the incident angle of the oblique incident light to the light receiving surface of the solar battery cell is reduced, the oblique incident light received by the light receiving surface of the solar battery cell is reduced. The light flux density is increased, and the power generation efficiency when obliquely incident light is incident can be improved.

  According to the invention of claim 3, since the incident angle of the oblique incident light to the light receiving surface of the solar battery cell becomes small, the luminous flux density of the oblique incident light received by the light receiving surface of the solar battery cell becomes large, and the oblique incident light It is possible to improve the efficiency of power generation when is incident.

  According to the invention of claim 4, since the oblique incident light is condensed, the luminous flux density of the oblique incident light received by the light receiving surface of the solar battery cell is increased, and the power generation efficiency when the oblique incident light is incident is increased. Can be improved.

  According to the invention of claim 5, light having a sufficient light flux density reaches the light receiving surface of the solar battery cell even when obliquely incident light is incident from either the direction close to the first direction or the direction close to the second direction. Therefore, it is possible to generate power efficiently both at sunrise and before sunset.

  According to the sixth to seventh aspects of the present invention, the incidence of obliquely incident light on one minute optical element is suppressed from being blocked by another adjacent minute optical element. Power generation.

  According to the invention of claim 8, since the electric power generated by the oblique incident light can be collected efficiently, the power generation efficiency when the oblique incident light is incident can be improved.

  According to the ninth aspect of the present invention, the power generated by the oblique incident light and the power generated by the vertical incident light and the substantially perpendicular incident light can be separated and collected. The efficiency of power generation can be improved both when incident light and substantially perpendicular incident light are incident.

  According to invention of Claim 10, since the light-receiving surface of a photovoltaic cell becomes flat, it becomes difficult to make a space | gap between a photovoltaic cell and a transparent body. Thereby, the power generation efficiency of the solar cell panel can be improved.

  According to the eleventh aspect of the invention, since the surface electrode does not shield the incident light, the incident light received by the photoelectric conversion body increases, and the power generation efficiency of the solar battery cell can be improved.

  According to the invention of claim 12, since the light receiving surface of the solar cell panel becomes flat, the adhesion of foreign matter to the light receiving surface of the solar cell panel is reduced, and the removal of foreign matter from the light receiving surface of the solar cell panel is easy. become. Thereby, deterioration of the efficiency of the electric power generation by a foreign material can be suppressed.

  According to the invention of claim 13, since the gap between the solar battery cell and the first transparent body is eliminated, the loss of incident light due to the gap can be suppressed and the efficiency of power generation can be improved.

  According to invention of Claim 14, the electric power which the solar cell panel generated can be collected efficiently.

<1 First Embodiment>
<1.1 Outline of Solar Cell Panel 102>
The first embodiment relates to a solar cell panel 102. FIG. 1 is a schematic diagram of the solar cell panel 102 of the first embodiment. FIG. 1 is a perspective view of the solar cell panel 102.

  As shown in FIG. 1, the solar battery panel 102 includes a solar battery cell 104 that generates electric power according to light received by the light receiving surface, and a light receiving surface of the solar battery cell 104 after increasing the luminous flux density of oblique incident light. And a plate-like or film-like transparent body 118 that guides normal incident light and substantially normal incident light to the light receiving surface of the solar battery cell 104 as they are. “Obliquely incident light” means incident light having a relatively large incident angle θ, and “substantially perpendicular incident light” means that the incident angle θ is relatively small and substantially in the normal direction to enter the light receiving surface of the solar cell 104. Incident light that is incident in parallel, “vertical incident light” is incident light that is incident in parallel to the normal direction that enters the light receiving surface of the solar battery cell 104 at an incident angle θ of 0 °.

  The transparent body 118 covers the entire light receiving surface of the solar battery cell 104. The transparent body 118 allows light having a sufficient luminous flux density to reach the light receiving surface of the solar battery cell 104 regardless of whether obliquely incident light, normal incident light, or substantially normal incident light is incident. Thereby, it is possible to generate power efficiently by the sun moving in a diurnal motion. A part of the light receiving surface of the solar battery cell 104 may be exposed without being covered with the transparent body 118.

<1.2 Transparent body 118>
(A) Outline of the transparent body 118;
2 to 4 are schematic views of the solar cell panel 102. 2 is a plan view of the solar cell panel 102, FIG. 3 is a cross-sectional view of the solar cell panel 102 at the position of the cutting line indicated by AA in FIG. 2, and FIG. 4 is indicated by BB in FIG. It is sectional drawing of the solar cell panel 102 in the position of the cutting line. 2 to 4, for convenience of explanation, an XYZ orthogonal coordinate system in which the XY plane is parallel to the light receiving surface 1041 of the solar battery cell 104 and the + Z direction is a normal direction exiting from the light receiving surface 1041 of the solar battery cell 104 is shown. Is defined.

  As shown in FIGS. 2 to 4, on the upper surface 1181 of the transparent body 118 that does not face the light receiving surface 1041 of the solar battery cell 104, the light incident surface of the solar battery cell 104 is increased after increasing the luminous flux density of the incident oblique incident light. A group of microlens / microprism composites 120 which are micro optical elements leading to the surface is formed so as to protrude from a flat portion 1183 parallel to the lower surface 1182. The entire lower surface 1182 of the transparent body 118 facing the light receiving surface 1041 of the solar battery cell 104 is flat. The lower surface 1182 of the transparent body 118 is in close contact with the light receiving surface 1041 of the solar battery cell 104. Thereby, since the gap between the solar battery cell 104 and the transparent body 118 is eliminated, loss of incident light due to the gap can be suppressed, and the power generation efficiency of the solar battery panel 102 can be improved.

(A) Material of the transparent body 118;
The transparent body 118 is a solid material such as a cured product of a resin such as an acrylic resin, a polycarbonate resin, or a cycloolefin resin, a cured product of a glass such as quartz glass, or a sintered body of a ceramic such as yttrium oxide ceramics. It is desirable to use a material that has good translucency at the wavelength of light that improves the power generation efficiency of the cell 104. The refractive index of the transparent body 118 is larger than the refractive index of air.

(C) Structure of the microlens / microprism composite 120;
As shown in FIGS. 3 and 4, the microlens / microprism complex 120 includes an incident surface 1201 on which oblique incident light is incident and a reflecting surface 1202 that totally reflects the oblique incident light incident on the incident surface 1201.

  The incident surface 1201 is a convex curved surface with the center protruding outward. The incident surface 1201 is a convex lens surface that collects incident oblique incident light. Since the incident light is collected by the incident surface 1201, the luminous flux density of the oblique incident light received by the light receiving surface 1041 of the solar battery cell 104 is increased, and the efficiency of power generation when the oblique incident light is incident is improved. be able to.

  The reflection surface 1202 is flat. The reflecting surface 1202 is bent toward the −Z direction, which is the normal direction of entering the light receiving surface 1041 of the solar battery cell 104, with the traveling direction of obliquely incident light incident on the incident surface 1201. Of course, the traveling direction of the obliquely incident light after being totally reflected by the reflecting surface 1202 varies depending on the incident angle of the obliquely incident light, so that “to the −Z direction, which is the normal direction to the light receiving surface 1041 of the solar battery cell 104”. “Bend toward” means that the traveling direction of the oblique incident light after being totally reflected by the reflecting surface 1202 is bent in the normal direction to enter the light receiving surface 1041 of the solar cell 104 regardless of the incident angle of the oblique incident light. It doesn't mean anything. That is, a normal line that enters the light receiving surface 1041 of the solar battery cell 104 in the traveling direction after being totally reflected by the reflecting surface 1202 of obliquely incident light that is incident parallel or substantially parallel to the optical axis of the microlens formed by the convex lens surface. Bending in the direction is sufficient. Since the incident angle of the oblique incident light to the light receiving surface 1041 of the solar battery cell 104 is reduced by the reflection surface 1202, the light flux density of the oblique incident light received by the light receiving surface 1041 of the solar battery cell 104 is increased, and the oblique incident light It is possible to improve the efficiency of power generation when is incident.

  The microlens / microprism composite 120 has only one reflecting surface that reflects obliquely incident light, but the traveling direction of the obliquely incident light is bent toward the normal direction that enters the light receiving surface 1041 of the solar battery cell 104. If possible, the microlens / microprism composite 120 may have two or more reflecting surfaces. However, having only one reflective surface has the advantage that the loss of obliquely incident light is reduced and the microlens / microprism composite 120 is small.

  Alternatively, a silver or aluminum film may be vapor-deposited on the reflective surface 1201, and the reflective surface may be used as a mirror.

(D) Oblique incidence area and normal incidence area;
The group of incident surfaces 1201 of the microlens / microprism complex 120 is a group of discrete oblique incident regions that make a relatively large angle with the light receiving surface 1041 of the solar battery cell 104 and occupy a relatively small range. The oblique incident light mainly enters the oblique incident region.

  The flat portion 1183 is a normal incidence region that makes a relatively small angle with the light receiving surface 1181 of the solar battery cell 104 and occupies a relatively large range. Normal incident light is mainly incident on the normal incidence region.

  The microlens / microprism composite 120 is formed outside the normal incidence region occupying a relatively large range. This contributes to reducing the incidence of normal incident light and substantially normal incident light on the normal incident region from interfering with the microlens / microprism composite 120.

  The area occupied by the normal incidence region on the upper surface 1181 of the transparent body 118 is preferably 10-50%. This is because if it falls below this range, there are many cases where the efficiency of power generation is not sufficient when normal incident light and substantially perpendicular incident light are incident. If this range is exceeded, the area occupied by the oblique incident region becomes small, and This is because there are many cases where the efficiency of power generation when incident light is incident is insufficient.

(E) an array of groups of microlens / microprism composites 120;
As shown in FIG. 2, the group of the microlens / microprism complex 120 is arranged sparsely at equal intervals in the ± X direction and densely arranged at equal intervals in the ± Y direction. Thereby, it is suppressed that the incident to the microlens / microprism complex 120 of one obliquely incident light incident from a direction close to the ± X direction is blocked by another adjacent microlens / microprism complex 120, The efficiency of power generation when obliquely incident light is incident can be improved.

  When the solar cell panel 102 is used for power generation by the sun moving diurnally, obliquely incident light is incident only in the time zone after sunrise or before sunset, so the group of the microlens / microprism complex 120 is It does not matter if they are discretely arranged only in the ± X direction and continuously arranged in the ± Y direction. However, although the oblique incident light that can increase the light beam density is reduced, the group of the microlens / microprism composite 120 may be discretely arranged in the ± Y directions. That is, the group of the microlens / microprism complex 120 is desirably arranged discretely in at least one direction, but may be arranged discretely in two directions.

  The height h of the microlens / microprism composite 120 is desirably 0.1 to 1.0 times the arrangement interval p in the direction of discrete arrangement of the group of microlens / microprism composite 120 ( (See FIG. 3). Typically, the height h is 5-5000 μm, and the arrangement interval p is 25-25000 μm. As a result, the incidence of obliquely incident light on one microlens / microprism composite 120 is suppressed from being blocked by another adjacent microlens / microprism composite 120, so that the sun moves more efficiently. Power generation.

(F) the microlens / microprism complex 122 for the time zone after sunrise and the microlens / microprism complex 124 for the time zone before sunset;
As shown in FIGS. 2 to 4, the group of microlens / microprism composites 120 includes a microlens / microscope for a time zone after sunrise in which the incident surface 1201 faces in a direction inclined from the −X direction to the + Z direction. It includes a group of prism complexes 122 and a group of microlenses / microprism complexes 124 for the time zone before sunset where the incident surface 1201 faces the direction inclined from the + X direction to the + Z direction. As a result, light with a sufficient luminous flux density reaches the light receiving surface of the solar battery cell 104 regardless of whether the oblique incident light is incident from either the direction close to the + X direction or the direction close to the −X direction. It is possible to generate power efficiently both during the time period.

  The micro lens / micro prism composite 122 for the time zone after sunrise and the micro lens / micro prism composite 124 for the time zone before sunset are alternately arranged one by one in the ± Y direction, and in the ± X direction. Each row of the arranged microlens / microprism composites 120 includes a microlens / microprism composite 122 for the time zone after sunrise or a microlens / microprism composite 124 for the time zone before sunset, respectively. It consists of only one. However, it is not essential to employ such an arrangement, and other arrangements may be adopted.

(G) State when obliquely incident light is incident;
5 to 7 are schematic diagrams showing states when obliquely incident light 191 to 193 is incident on the solar cell panel 102. FIGS. 5 to 7 are cross-sectional views schematically showing parallel light beams of obliquely incident light 191 to 193 incident at a part of the cross-sectional view of FIG. 3 at incident angles θ1, θ2, and θ3.

  As shown in FIG. 5, when obliquely incident light 191 is incident on the solar cell panel 102 at an incident angle θ1 substantially parallel to the optical axis of the microlens, it is almost blocked by the adjacent microlens / microprism composite 120. All of the oblique incident light 191 is incident only on the incident surface 1201 of the microlens / microprism 120. The oblique incident light 191 incident on the incident surface 1201 of the microlens / microprism is condensed on the incident surface 1201 and then travels on the reflecting surface 1202 toward the normal direction entering the light receiving surface 1041 of the solar cell 104. It is bent and finally reaches the light receiving surface 104 of the solar battery cell 104.

  Further, as shown in FIG. 6, when the oblique incident light 192 is incident on the solar cell panel 102 at an incident angle θ2 near the upper limit larger than the incident angle θ1, it is blocked by the adjacent microlens / microprism complex 120. Although the luminous flux increases, all of the oblique incident light 192 is incident only on the incident surface 1201 of the microlens / microprism composite 120. The oblique incident light 192 incident on the incident surface 1201 of the microlens / microprism composite 120 is again condensed on the incident surface 1201 and then travels on the reflecting surface 1202 to enter the light receiving surface 1041 of the solar cell 104. It is bent in a direction slightly inclined from the linear direction, and finally reaches the light receiving surface 1401 of the solar battery cell 104. The upper limit of the incident angle θ is approximately about 30 °.

  Further, as shown in FIG. 7, when the oblique incident light 193 is incident on the solar cell panel 102 at an incident angle θ3 near the lower limit smaller than the incident angle θ1, a part of the oblique incident light 193 is a microlens / microprism. The light enters the incident surface 1201 of the composite 120, and a part of the oblique incident light enters the flat portion 1183. The obliquely incident light 193 incident on the incident surface 1201 of the microlens / microprism composite 120 is collected on the incident surface 1201 and then travels on the reflecting surface 1202 in a direction slightly inclined from the normal direction entering the light receiving surface. It is bent and finally reaches the light receiving surface 1041 of the solar battery cell 104. The obliquely incident light incident on the flat portion 1183 reaches the light receiving surface 1041 of the solar battery cell 104 as it is after being slightly bent. The lower limit of the incident angle θ is approximately about 5 °.

  Thus, the obliquely incident light incident on the incident surface 1201 of the microlens / microprism complex 120 is guided to the light receiving surface 1041 of the solar battery cell 104 after the luminous flux density is increased. Further, as shown in FIGS. 5 to 7, even when the incident angle θ is large, the microlens / microprism composite 120 also collects light that has not conventionally reached the solar cell due to surface reflection. It becomes available for light. However, the oblique incident light incident on the incident surface 1201 of the microlens / microprism composite 120 decreases as the incident angle θ of the oblique incident light 120 decreases. Therefore, when the incident angle θ of the oblique incident light decreases, the microlens / The role of increasing the light beam density of the microprism composite 120 is less likely to work.

  FIG. 8 is a schematic diagram illustrating a state where oblique incident light is incident on the solar cell panel 102. FIG. 8 is a plan view schematically showing parallel light beams of oblique incident light 194 to 199 having different seasons and times in part of the plan view of FIG.

  As shown in FIG. 8, the incident direction of the oblique incident light when the solar cell panel 102 is viewed in plan changes depending on the season and time, but the change is due to the acquisition of the oblique incident light by the microlens / microprism complex 120. Has little effect.

(H) State when normal incident light and substantially normal incident light are incident;
FIG. 9 and FIG. 10 are schematic views showing a state where the normal incident light 181 and the substantially normal incident light 182 are incident on the solar cell panel 102, respectively. 9 and 10 are cross-sectional views schematically showing a parallel light beam of the normal incident light 182 and the substantially normal incident light 182 incident on the part of the cross-sectional view of FIG. 3 at an incident angle θ4.

  As shown in FIG. 9, when the normal incident light 181 enters the solar cell panel 102, most of the normal incident light 181 enters the flat portion 1183 without interfering with the microlens / microprism composite 120, A small portion of the normal incident light 181 interferes with the microlens / microprism composite 120. The vertically incident light 181 incident on the flat portion 1183 reaches the light receiving surface 1041 of the solar battery cell 104 almost as it is. The normal incident light 120 that has interfered with the microlens / microprism composite 120 is scattered by the microlens / microprism composite 120, and then part of the light reaches the light receiving surface 1041 of the solar cell 104.

  In addition, as shown in FIG. 10, when the substantially vertical incident light 182 is incident on the solar cell panel 102, the light beam that interferes with the microlens / microprism composite 120 slightly increases, but most of the substantially vertical incident light 182 The light enters the flat portion without interfering with the microlens / microprism composite 120, and a small portion of the substantially perpendicular incident light 182 interferes with the microlens / microprism composite 120. The substantially perpendicular incident light 182 incident on the flat portion 1183 reaches the light receiving surface 1041 of the solar battery cell 104 almost as it is. Part of the substantially perpendicular incident light 182 that interferes with the microlens / microprism composite 120 reaches the light receiving surface 1041 of the solar cell 104 after being scattered by the microlens / microprism composite 120.

  In this manner, the normal incident light 181 and the substantially normal incident light 182 incident on the flat portion 1183 are almost directly guided to the light receiving surface 1041 of the solar battery cell 104. Further, the normal incident light 181 and the substantially normal incident light 182 that interfere with the microlens / microprism composite 120 are scattered by the microlens / microprism composite 120, and finally a part of the light is received by the solar battery cell 104. The surface 1041 is reached.

  Therefore, even after the incident angle of incident light is reduced and the role of increasing the light beam density of the microlens / microprism composite 120 is less likely to work, the vertical impact is hardly affected by the microlens / microprism composite 120. Electric power is efficiently generated by the incident light 181 and the substantially perpendicular incident light 182.

<1.3 Solar cell 104>
(A) Outline of solar battery cell 104;
As shown in FIG. 2 to FIG. 4, the solar battery cell 104 is generated on the photoelectric conversion body 106 that performs photoelectric conversion and the light receiving surface 1041 and the non-light receiving surface 1042 of the solar battery cell 104. A front electrode 108 and a back electrode 116 serving as a power collecting path are provided.

(A) the photoelectric converter 106;
For example, the photoelectric converter 106 has an n-type layer in the vicinity of the light-receiving surface 1061 by diffusion of donor impurities such as boron (B), and a p ⁺ -type layer in the vicinity of the non-light-receiving surface 1062 by diffusion of acceptor impurities such as aluminum. This is a p-type silicon semiconductor substrate. The silicon semiconductor may be any of single crystal, polycrystal, microcrystal, and amorphous. Of course, the conductivity type may be reversed, or the semiconductor material may be changed to other types such as germanium (Ge), gallium arsenide (GaAs), indium phosphide (InP).

  As shown in FIGS. 2 to 4, a groove 1063 in which the surface electrode 108 is embedded is formed on the light receiving surface 1061 of the photoelectric conversion body 106.

(C) surface electrode 108;
The surface electrode 108 is a film of a transparent conductive material such as tin-doped indium oxide (ITO). Thereby, since the surface electrode 108 does not shield the incident light, the incident light received by the photoelectric converter 106 is increased, and the power generation efficiency can be improved.

  As shown in FIGS. 2 to 4, the surface electrode 108 is embedded in the groove 1063. A portion of the surface electrode 108 exposed to the light receiving surface 1041 of the solar battery cell 104 and a portion other than the portion where the groove 1063 of the light receiving surface 1061 of the photoelectric converter 106 is formed constitute the same plane. Thereby, since the light receiving surface 1041 of the solar battery cell 104 becomes flat, it becomes difficult to form a gap between the solar battery cell 104 and the transparent body 118. This contributes to improving the efficiency of power generation.

  The surface electrode 108 receives obliquely incident light incident on the incident surface 1201 of the microlens / microprism complex 122 for the time zone after sunrise and the microlens / microprism complex 124 for the time zone before sunset. It has a group of linear finger electrodes 110 and a group of finger electrodes 112 adjacent to the obliquely incident light receiving regions 1044 and 1045 on the light receiving surface 1041 of the solar cell 104 that reaches and extending in the ± Y direction. Since the group of finger electrodes 110 and the group of finger electrodes 112 can efficiently collect the power generated by the oblique incident light incident in the time zone after sunrise and the time zone before sunset, the time after sunrise It is possible to improve the efficiency of power generation when obliquely incident light is incident in the band and the time zone before sunset.

  Further, the surface electrode 108 is provided at substantially the center of the vertical incident light receiving region 1046 on the light receiving surface 1041 of the solar cell 104 to which the vertical incident light and the substantially vertical incident light that have entered the flat portion 1183 arrive. A group of linear finger electrodes 114 extending in the direction is provided. The group of finger electrodes 114 can efficiently collect the power generated by the normal incident light and the substantially normal incident light, so that the efficiency of power generation when the normal incident light is incident can be improved.

  The group of finger electrodes 110, the group of finger electrodes 112, and the group of finger electrodes 114 are electrically separated. This separates and collects the power generated by the oblique incident light incident in the time zone after sunrise, the power generated by the oblique incident light incident in the time zone before sunset, and the power generated by the normal incident light. Therefore, the efficiency of power generation when obliquely incident light is incident after the sunrise time zone, when obliquely incident light is incident in the time zone before sunset, and when normal incident light and substantially perpendicular incident light are incident Can be improved.

  The electrical connection between each of the groups of finger electrodes 110, 112, and 114 is performed by, for example, a bus bar electrode provided in the solar battery cell 104.

(D) Back electrode 116;
The back electrode 116 is a film of a conductive material such as aluminum, for example. As shown in FIGS. 2 to 4, the back electrode 116 is formed on the entire surface of the non-light-receiving surface 1062 of the photoelectric converter 106.

<2 Second Embodiment>
The second embodiment relates to a solar cell panel 202. The difference between the solar cell panel 202 of the second embodiment and the solar cell panel 102 of the first embodiment is that the solar cell panel 202 of the second embodiment is different from the microlens / microprism composite 120 of the first embodiment. Instead, the microprism 220 is formed on the transparent body 218.

  FIG. 11 is a schematic diagram of the solar cell panel 202 of the second embodiment. FIG. 11 is a cross-sectional view of the solar cell panel 202 corresponding to FIG. 3 of the first embodiment.

  As shown in FIG. 11, the solar battery panel 202 includes solar battery cells 204 and a transparent body 218. The solar battery cell 204 is the same as the solar battery cell 104 of the first embodiment. On the upper surface 2181 of the transparent body 218, a group of microprisms 220 that are micro optical elements that guide incident obliquely incident light to the light receiving surface 2041 of the solar battery cell 204 after increasing the luminous flux density is a flat portion parallel to the lower surface 2182. 2183 protruding from 2183.

  The microprism 220 includes an incident surface 2201 on which oblique incident light is incident and a reflecting surface 2202 that totally reflects the oblique incident light incident on the incident surface 2201.

  Unlike the case of the microlens / microprism composite 120, the incident surface 2201 that is a discrete oblique incident region that forms a relatively large angle with the light receiving surface 2041 of the solar cell 204 and occupies a relatively small range is flat. It has become.

  The reflection surface 2202 is flat as in the case of the microlens / microprism composite 120. The reflecting surface 2202 is bent so that the traveling direction of obliquely incident light incident on the incident surface 2201 is a normal direction entering the light receiving surface 2041 of the solar battery cell 204. Since the incident angle of the oblique incident light to the light receiving surface 2041 of the solar battery cell 204 is reduced by the reflecting surface 2202, the luminous flux density of the oblique incident light received by the light receiving surface 2041 of the solar battery cell 204 is increased, and the oblique incident light It is possible to improve the efficiency of power generation when is incident.

  Also in the case of the solar battery panel 202, the normal incident light and the substantially vertical light incident on the flat portion 2183, which is a flat vertical incident area that makes a relatively small angle with the light receiving surface 2041 of the solar battery cell 204 and occupies a relatively large range. Incident light is guided almost directly to the light receiving surface 2041 of the solar battery cell 204. Further, the normal incident light and the substantially normal incident light that interfere with the microprism 220 are scattered by the microprism 220 and finally part of the light reaches the light receiving surface 2041 of the solar battery cell 204.

  Therefore, even after the incident angle of the incident light is reduced and the role of increasing the light beam density of the microprism 220 is less likely to work, it is more efficient by the normal incident light and the substantially vertical incident light with almost no influence of the microprism 220. Electricity is generated.

  That is, also in the case of the solar battery panel 202, the transparent body 218 guides the oblique incident light to the light receiving surface of the solar battery cell 204 after increasing the luminous flux density, and directs the normal incident light to the light receiving face of the solar battery cell 204 as it is. Have a guiding role. As a result, light having a sufficient light flux density reaches the light receiving surface of the solar battery cell 204 regardless of whether obliquely incident light, normal incident light, or substantially normal incident light is incident, and efficiently generates power by the sun moving diurnally. Can do.

  It is desirable that the groups of microprisms 220 are arranged in discrete directions in at least one direction, and the height h of the microprisms 220 is 0.1, which is an arrangement interval p in the direction in which the groups of microprisms 220 are arranged in a discrete manner. -1.0 times (see FIG. 11), typically the height h is 5-5000 μm, the array interval p is 25-25000 μm, for the time zone after sunrise and before sunset It is desirable to provide the time zone micro prism 220 as in the first embodiment.

<3 Third Embodiment>
The third embodiment relates to a solar cell panel 302. The difference between the solar cell panel 302 of the third embodiment and the solar cell panel 102 of the first embodiment is that the solar cell panel 302 of the third embodiment is different from the microlens / microprism composite body 120 of the first embodiment. Instead, the microlens 320 is formed on the transparent body 318, and the positions of the finger electrodes 310, 312, and 314 are changed.

  FIG. 12 is a schematic diagram of the solar cell panel 302 of the third embodiment. FIG. 12 is a cross-sectional view of the solar cell panel 302 corresponding to FIG. 3 of the first embodiment.

  As shown in FIG. 12, the solar battery panel 302 includes solar battery cells 304 and a transparent body 318. The solar battery cell 304 is the same as the solar battery cell 104 of the first embodiment except for the positions of the finger electrodes 310, 312, and 314. On the upper surface 3181 of the transparent body 318, a group of microlenses 320, which are micro optical elements that guide the incident oblique incident light to the light receiving surface 3041 of the solar battery cell 304 after increasing the luminous flux density, are formed to protrude.

  The microlens 320 has an incident surface 3201 on which oblique incident light is incident.

  The incident surface 3201 that is a discrete oblique incident region that makes a relatively large angle with the light receiving surface 3041 of the solar battery 304 and occupies a relatively small range is a convex curved surface with the center protruding outward. . Similar to the case of the microlens / microprism complex 120, the incident surface 3201 is a convex lens surface that collects incident oblique incident light. Since the oblique incident light is collected by the incident surface 3201, the luminous flux density of the oblique incident light received by the light receiving surface 3041 of the solar battery cell 304 is increased, and the efficiency of power generation when the oblique incident light is incident is improved. be able to.

  Also in the case of the solar battery panel 302, the vertical incident light and the substantially vertical light incident on the flat portion 3043 that is a flat vertical incident area that forms a relatively small angle with the light receiving surface 3041 of the solar battery cell 304 and occupies a relatively large range. Incident light is guided almost directly to the light receiving surface 3043 of the solar battery cell 304. Further, the normal incident light and the substantially normal incident light that interfere with the microlens 320 are scattered by the microlens 320 and finally reach the light receiving surface of the solar battery cell 304. The flat portion 3043 is inclined from a state parallel to the lower surface 3182 of the transparent body 318.

  Accordingly, even after the incident angle of incident light is reduced and the role of increasing the light flux density of the microlens 320 is less likely to work, the incident light is more efficiently affected by the normal incident light and the substantially perpendicular incident light with almost no influence of the microlens 320. Electricity is generated.

  That is, also in the case of the solar battery panel 302, the transparent body 318 guides the oblique incident light to the light receiving surface 3041 of the solar battery cell 304 after increasing the luminous flux density and substantially directly accepts the vertical incident light as the light receiving face of the solar battery cell 304. The light having a sufficient light flux density reaches the light receiving surface 3041 of the solar battery cell 304 regardless of whether obliquely incident light, vertical incident light, or substantially vertical incident light is incident. Thereby, it is possible to generate power efficiently by the sun moving in a diurnal motion.

  In the case of the solar battery panel 302, the oblique incident light 391 is not bent in the normal direction to enter the light receiving surface 3041 of the solar battery cell 304, so that the oblique incident light incident on the incident surface 3201 of the microlens 320 reaches the sun. The positions of the oblique incident light receiving regions 3044 and 3045 on the light receiving surface 3041 of the battery cell 304 are different from those of the solar battery panel 102. However, the finger electrode 310 extending in the ± Y direction adjacent to the oblique incident light receiving regions 3044 and 3046 on the light receiving surface 3041 of the solar battery cell 304 to which the oblique incident light incident on the incident surface 3201 of the microlens 320 reaches. And the group of finger electrodes 312, and the normal incident light receiving region 3046 on the light receiving surface 3104 of the solar cell 104 to which the normal incident light and the substantially perpendicular incident light incident on the flat portion 3043 reach. The surface electrode 308 includes a group of linear finger electrodes 314 extending in the ± Y direction, and the group of finger electrodes 310, the group of finger electrodes 312 and the group of finger electrodes 314 are electrically separated. The point that it is desirable to do so is the same as in the case of the solar battery panel 102.

  It is desirable that the groups of microlenses 320 are discretely arranged in at least one direction, and the height h of the microlenses 320 is 0.1, which is an arrangement interval p in the direction in which the groups of microlenses 320 are discretely arranged. -1.0 times (see FIG. 12), typically the height h is 5-5000 μm, the array interval p is 25-25000 μm, for the time zone after sunrise and before sunset It is desirable to provide the micro lens 320 for the time zone as in the case of the first embodiment.

<4 Fourth Embodiment>
The fourth embodiment relates to a solar cell panel 402. FIG.13 and FIG.14 is a schematic diagram of the solar cell panel 402 of 4th Embodiment. 13 is a perspective view of the solar cell panel 402, and FIG. 14 is a cross-sectional view of the solar cell panel 402 corresponding to FIG. 3 of the first embodiment.

  As shown in FIGS. 13 and 14, the solar battery panel 402 includes the same solar battery cell 404 and first transparent body 418 as the solar battery cell 104 and transparent body 118 of the first embodiment, and the first transparent body 418. And a second transparent body 426 for protecting.

  As shown in FIG. 13, the second transparent body 426 covers the upper surface 4181 of the first transparent body 418. The upper surface 4261 of the second transparent body 426 that does not face the upper surface 4181 of the first transparent body 418 is flat. As a result, the light receiving surface of the solar cell panel 402 becomes flat, so that the adhesion of foreign matter to the light receiving surface 4021 of the solar cell panel 402 is reduced and the foreign matter is easily removed from the light receiving surface 4021 of the solar cell panel 402. Therefore, it is possible to suppress the deterioration of the power generation efficiency due to the foreign matter. The lower surface 4262 of the second transparent body 426 facing the upper surface 4181 of the first transparent body 418 has irregularities corresponding to the unevenness of the upper surface 4181 of the first transparent body 418. Thereby, since the gap between the first transparent body 418 and the second transparent body 418 is eliminated, the loss of incident light due to the gap can be suppressed, and the power generation efficiency of the solar cell panel 402 can be improved.

  As with the first transparent body 418, the second transparent body 426 is preferably made of a material having good translucency at a wavelength of light that allows the solar battery 404 to efficiently generate power. However, in order to suppress reflection of incident light at the interface between the first transparent body 418 and the second transparent body 426, the refractive index of the second transparent body 426 is higher than the refractive index of the first transparent body 418. Small is desirable. The second transparent body 426 is manufactured by, for example, applying a fluid containing silicon dioxide, fluorine, or the like to the upper surface 4181 of the first transparent body 418 and then curing the fluid.

  The solar battery 404 and the first transparent body 418 are not the same as the solar battery 104 and the transparent body 118 of the first embodiment, but the same as the solar battery 204 and the transparent body 218 of the second embodiment. Or you may employ | adopt the same thing as the photovoltaic cell 304 and the transparent body 318 of 3rd Embodiment.

<5 Fifth Embodiment>
The fifth embodiment relates to a solar power generation device 502.

  FIG. 15 is a block diagram of the solar power generation device 502 of the fifth embodiment.

  As shown in FIG. 15, the photovoltaic power generation apparatus 502 includes a plurality of solar battery panels 102 according to the first embodiment having a plurality of power collection paths having different power output dependencies with respect to an incident angle of incident light, And a current collection circuit 532 that selectively collects current from the current collection paths that are dominant among the current collection paths. The current collection circuit 532 can improve power generation efficiency. Instead of the solar cell panel 102 of the first embodiment, any one of the solar cell panels 202, 302, and 402 of the second to fourth embodiments may be adopted.

  The current collection circuit 532 includes selection circuits 534 and 536 that selectively collect current from a current collection path having a high voltage absolute value. At the input of the selection circuit 534, the obliquely incident light is incident on the finger electrode 110, which is a current collecting path that outputs a large amount of power when obliquely incident light is incident in the time zone after sunrise, and the time zone before sunset. The finger electrode 112, which is a current collecting path that sometimes outputs a large amount of power, is connected, and the input of the selection circuit 536 receives a large amount of power when the output of the selection circuit 534 and the normal incident light or the substantially normal incident light enter. The finger electrode 114 which is a current collection path to be output is connected, and the output of the selection circuit 536 becomes a negative output terminal 537 of the current collection circuit. A positive output terminal 538 of the current collector circuit 532 is connected to the back electrode 116.

  Thereby, current collection is performed from the finger electrode 110, 112, 114 where the absolute value of the voltage is the highest.

  FIG. 16 is a circuit diagram of the selection circuits 534, 536 when the finger electrodes 110, 112, 114 are negative.

  As shown in FIG. 16, the selection circuits 534 and 536 include FETs (field effect transistors) 542 and 544 that become conductive between the drain D and the source S when an ON signal is applied to the gate G, and the input voltage of the positive input. Comparator 546 outputs a positive signal when the input voltage is greater than the negative input voltage and outputs a negative signal when the positive input voltage is greater than the negative input voltage, and inverts the positive and negative signals And an inverter 548.

  The FET 542 is inserted in the middle of the power supply path 550 connecting the first input 554 and the output 558, and electrically connects the first input 554 and the output 558 when a positive signal is given to the gate G as an ON signal. Connecting. Similarly, the FET 544 is inserted in the middle of a power supply path 552 connecting the second input 556 and the output 558, and when the positive signal is given to the gate G as an ON signal, the second input 556 and the output 558 are connected. Connect electrically. The positive input of the comparator 546 is connected to the first input 554, the negative input is connected to the second input 556, and the output is connected to the gate G of the FET 542 via the inverter 548 and directly connected to the gate G of the FET 544. .

  When the absolute value | V1 | of the input voltage of the first input 554 becomes higher than the absolute value | V2 | of the input voltage of the second input 556 (| V1 |> | V2 |, ie, V1 <V2), the comparator 546 becomes negative. A signal is output, and a positive signal is applied to the gate G of the FET 542 and a negative signal is applied to the gate G of the FET 544. Thereby, the drain D and the source S of the FET 542 are brought into conduction, and the drain D and the source S of the FET 544 are brought out of conduction. On the other hand, when the absolute value | V2 | of the input voltage of the second input 556 becomes higher than the absolute value | V1 | of the input voltage 554 of the first input (| V2 |> | V1 |, ie, V2 <V1), the comparator 546 Outputs a positive signal, a negative signal is applied to the gate G of the FET 542, and a positive signal is applied to the gate G of the FET 544. As a result, the drain D and source S of the FET 542 are turned off, and the drain D and source S of the FET 544 are turned on.

  The selection circuits 534 and 536 shown in FIG. 16 are merely examples, and the conduction state of the switching element inserted in the power feeding path connecting the input and the output is controlled according to the magnitude of the input voltage, and the absolute value of the voltage is large. It can be replaced with another selection circuit that electrically connects the input and the output. For example, a switching element other than an FET, such as a bipolar transistor or a relay, may be used. In addition, in order to prevent a phenomenon in which the finger electrodes that supply power to the load are alternately switched in a short time due to an increase in the absolute value of the voltage of the finger electrodes that are in the no-load state, It may be connected to a pseudo load such as a resistor, or the operation of the comparator may have a hysteresis characteristic.

<6 Sixth Embodiment>
The sixth embodiment relates to a current collector circuit 632 that can be employed instead of the current collector circuit 532 of the fifth embodiment.

  FIG. 17 is a circuit diagram of the current collector circuit 632 of the sixth embodiment. FIG. 17 is a circuit diagram of the current collector circuit 632 when the finger electrodes 110, 112, and 114 are negative.

  As shown in FIG. 17, the current collecting circuit 632 is in a conductive state when a voltage is applied in the forward direction, and a diode 652, 654, 656 is in a non-conductive state when a forward current flows and a voltage is applied in the reverse direction. Is provided. In the diodes 652, 654, and 656, currents flowing from the back electrode 116 to the finger electrodes 110, 112, and 114 along the power supply paths 658, 660, and 662 that connect the finger electrodes 110, 112, and 114 and the negative output end 664, respectively. It is inserted so as to have a forward current. The positive output terminal 666 of the current collector circuit 632 is connected to the back electrode 116.

  Thereby, current collection is performed from the finger electrode 110, 112, 114 where the absolute value of the voltage is the largest.

<7 Seventh Embodiment>
The seventh embodiment relates to a current collector circuit 732 that can be employed instead of the current collector circuit 532 of the fifth embodiment.

  FIG. 18 is a block diagram of a current collecting circuit 732 according to the seventh embodiment.

  As shown in FIG. 18, the current collection circuit 732 includes a timer 772 that outputs a set signal and a reset signal at the timing when the current collection path is switched, and a non-conducting state in which the reset signal is input when the set signal is input. And latch relays 774, 776, and 778 which are in a conductive state.

  Latch relays 774, 776, and 778 are inserted in the middle of power supply paths 758, 760, and 762 that connect finger electrodes 110, 112, and 114 and negative output end 764, respectively. A positive output terminal 766 of the current collector circuit 732 is connected to the back electrode 116. The output of timer 772 is applied to the windings of latch relays 774, 776, and 778.

  The timer 772 outputs a reset signal to the latch relays 752 and 756 and outputs a set signal to the latch relay 754 at the timing of shifting from the time zone after sunrise to the time zone during the day. In addition, the timer 772 outputs a reset signal to the latch relays 752 and 754 and outputs a set signal to the latch relay 756 at the timing of transition from the daytime time zone to the time zone before sunset. Further, the timer 772 outputs a reset signal to the latch relays 754 and 756 and outputs a set signal to the latch relay 752 at night.

  As a result, current collection is performed from the finger electrodes 110, 112, and 114 where the supply of electric power is generally the largest.

<8 Others>
The above description is illustrative in all aspects, and the present invention is not limited thereto. It is understood that countless variations that are not illustrated can be envisaged without departing from the scope of the present invention.

  In particular, it is naturally planned to use a combination of what has been described in the first to seventh embodiments. In the solar cell panel according to the present invention, the oblique incident light is guided to the solar cell after the luminous flux density is increased. Therefore, even when the solar cell panel is installed on the wall surface of a building or the like, It can generate electricity efficiently regardless of location.

It is a perspective view of the solar cell panel of a 1st embodiment. It is a top view of the solar cell panel of a 1st embodiment. It is sectional drawing of the solar cell panel 102 of 1st Embodiment in the position of the cutting line shown by AA of FIG. It is sectional drawing of the solar cell panel 102 of 1st Embodiment in the position of the cutting line shown by BB of FIG. It is sectional drawing which shows a state when obliquely incident light injects into the solar cell panel. It is sectional drawing which shows a state when obliquely incident light injects into the solar cell panel. It is sectional drawing which shows a state when obliquely incident light injects into the solar cell panel. It is a top view which shows a state when diagonally incident light injects into the solar cell panel. It is sectional drawing which shows a state when perpendicularly incident light injects into a solar cell panel. It is sectional drawing which shows a state when substantially perpendicular | vertical incident light injects into a solar cell panel. It is sectional drawing of the solar cell panel of 2nd Embodiment. It is sectional drawing of the solar cell panel of 3rd Embodiment. It is a perspective view of the solar cell panel of 4th Embodiment. It is sectional drawing of the solar cell panel of 4th Embodiment. It is a block diagram of the solar power generation device of 5th Embodiment. It is a circuit diagram of a selection circuit. It is a circuit diagram of the current collection circuit of 6th Embodiment. It is a block diagram of the current collection circuit of 7th Embodiment. It is a figure showing the outline of the relationship between the luminous flux density of the incident light which injects into a photovoltaic cell, and the electromotive force of a photovoltaic cell. It is a schematic diagram explaining the time which can generate electric power as a solar light source which carries out daily movement.

Explanation of symbols

102, 202, 302, 402 Solar panel 104, 204, 304 Solar cell 106 Photoelectric converter 108 Front surface electrode 110, 112, 114, 310, 312, 314 Finger electrode 116 Back surface electrode 118, 218, 318, 418 Transparent body 120 microlens / microprism complex 122 microlens / microprism complex for after sunrise 124 microlens / microprism complex for before sunset 220 microprism 320 microlens 426 transparent body 502 solar power generation device 532 current collector circuit 534 , 536 Selection circuit

Claims (14)

Solar cells,
A first transparent body covering a light receiving surface of the solar battery cell;
With
A discrete first incident region occupying a relatively small range at a relatively large angle with the light receiving surface of the solar battery cell on the first surface not facing the light receiving surface of the first transparent body. And a flat second incident region occupying a relatively large range with a relatively small angle with the light receiving surface of the solar cell,
A group of micro optical elements that guide obliquely incident light incident on the first incident region to the light receiving surface of the solar cell from the second incident region on the first transparent body. A solar cell panel that is discretely formed.   The minute optical element has an incident surface serving as a lens surface for collecting incident oblique incident light and a traveling direction of the oblique incident light incident on the incident surface toward a normal direction entering the light receiving surface of the solar battery cell. The solar cell panel according to claim 1, wherein the solar cell panel is a microlens / microprism having a reflecting surface that bends.   2. The micro-optical element is a micro prism having an incident surface and a reflecting surface that bends a traveling direction of oblique incident light incident on the incident surface toward a normal direction entering a light receiving surface of the solar battery cell. The solar cell panel as described in.   The solar cell panel according to claim 1, wherein the micro optical element is a micro lens having an incident surface serving as a lens surface for collecting incident oblique incident light. The group of micro optical elements is
A first group in which the incident surface faces a direction inclined from a first direction perpendicular to a normal direction exiting from the light receiving surface of the solar battery cell to a normal direction exiting from the light receiving surface of the solar cell;
The incident surface is inclined in a normal direction from the light receiving surface of the solar cell from a second direction perpendicular to the normal direction coming out from the light receiving surface of the solar cell and opposite to the first direction. A second group facing,
The solar cell panel according to claim 1, comprising: A group of the micro optical elements is discretely arranged in at least one direction;
The solar cell according to any one of claims 1 to 5, wherein a height of the micro optical element is 0.1 to 1.0 times an arrangement interval of the group of the micro optical elements in a discrete arrangement direction. panel.   7. The solar cell panel according to claim 6, wherein a height of the micro optical element is 5-5000 μm, and an arrangement interval in a direction in which the groups of the micro optical elements are discretely arranged is 25-25000 μm. The solar battery cell is
A photoelectric conversion body that performs photoelectric conversion;
A surface electrode provided on a light receiving surface of the photoelectric converter;
A back electrode provided on a non-light-receiving surface of the photoelectric converter;
With
The surface electrode is
A group of first finger electrodes adjacent to the first light receiving region on the light receiving surface of the solar cell to which the oblique incident light incident on the first incident region arrives;
A solar cell panel according to any one of claims 1 to 7, comprising: The surface electrode is
A second light receiving region provided on a light receiving surface of the solar cell on which the vertically incident light that is electrically separated from the group of the first finger electrodes and is incident on the second incident region arrives; A group of finger electrodes,
The solar cell panel according to claim 8, further comprising:   The surface electrode is embedded in a groove formed in the photoelectric converter, and a portion of the surface electrode exposed to the light receiving surface of the solar battery cell and a portion of the light receiving surface of the photoelectric converter other than the portion where the groove is formed The solar cell panel according to claim 8 or 9, wherein the portion forms the same plane.   The solar cell panel according to any one of claims 8 to 10, wherein the surface electrode is a film of a transparent conductive material. A third surface that covers the first surface of the first transparent body and does not face the first surface of the first transparent body is flat and has a refractive index smaller than that of the first transparent body. A second transparent body,
The solar cell panel according to any one of claims 1 to 11, further comprising:   The solar cell panel according to claim 12, wherein the second surface of the first transparent body facing the light receiving surface of the solar cell is in close contact with the light receiving surface of the solar cell. A solar cell panel having a plurality of current collecting paths having different power output dependencies with respect to an incident angle of incident light;
A current collecting circuit that selectively collects current from a dominant current collecting path among the plurality of current collecting paths;
A solar power generation device comprising:

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