1. Field of the Invention
The instant disclosure relates to a solar collector device, and particularly, to a solar collector device being used for improving solar power efficiency on a solar cell or on a concentrating solar thermal power generation system.
2. Description of Related Art
At present, solar cells are the mainstream in the solar power technology. But, biggest problem the solar cell faces is that, a photoelectric conversion efficiency of the solar cell is inferior, so as to cause insufficient electricity generation efficiency. For this reason, lots of solar panels are used to generate currents in a conventional solar power system, and it is costly.
In order to solve the problem of the solar cell having inferior photoelectric conversion efficiency, materials and manufacturing processes used in the solar cell of the conventional solar power system have been continuously modified to improve the photoelectric conversion efficiency, but breakthroughs are difficult. For example, using a III group material or a V group material to form a multilayer structure in the solar cell that has high photoelectric conversion efficiency. However, the multilayer structure of the III/V group material has to be cooperatively used with a fresnel lens and a biaxial tracking system, and extremely high precision is required therein to generate effective magnification. Otherwise, the effective magnification would be sharply decreased and it is still costly. Thus, a light collector device such as reflective plate or lens is gradually used to cooperate with the tracking system to increase the amount of sunlight passing through into such a silicon solar cell, so as to upgrade the photoelectric conversion efficiency.
In addition to the solar cells, a concentrated solar power (CSP) has been being developed at present. The CSP is a heat collector type solar power system. Reflectors or lenses are used to collect sunlight rays from a larger area to a relative tiny light collecting area to concentrate the sunlight rays based on optical principles. Accordingly, the light collecting area on a power generator is irradiated by sunlight to increase its temperature, a solar energy is converted into a heat energy based on photothermal conversion principles, and the heat energy then drives the power generator to generate electric power through a heat engine such as steam turbine engine.
In the abovementioned solar power system or concentrated solar power system, the reflective plate is usually used to concentrate the sunlight rays.
The light collection efficiency of the conventional reflective type solar collector device can be defined as an area of the effective light collecting area relative to an area of the light receiving surface 2 of the light energy conversion unit 1. When the effective light collecting area assembled by the reflective plates 3 (which is the area surrounded by each of the reflective plates 3 having a top opening) is larger, more sunlight rays can be concentrated on the light receiving surface 2 of the light energy conversion unit 1, so as to upgrade the amount of sunlight effectively passing through. Therefore, if the area of the effective light collecting area of the reflective plates 3 is increased, sunlight rays in a wider range can be concentrated on the light receiving surface 2 of the light energy conversion unit 1, and then the light collection efficiency of the light collector device can be increased.
In
However, in relation to the position of the reflective plate 3 irradiated by the sunlight rays being closer to an upper site on the reflective plate 3, the position of the light receiving surface 2 where the light rays reflected by the reflective plate 3 projects on is further away from an intersection of the light receiving surface 2 and the reflective plate 3. Therefore, when a height H of the reflective plate 3 is higher than a certain height, a projection point of the light ray reflected by the reflective plate 3 is located outside of the light receiving surface 2. As shown in
Referring to
The conventional reflective type solar collector device is further analyzed (shown in
Please refer to
Therefore, according to the abovementioned description, the increase rate of the effective collecting width W of the conventional reflective type solar collector device is limited by geometry, so that the increase rate of the effective collecting width W cannot be substantially increased. Otherwise, the reflective plate 3 will have excess height to cause the light collector device to have a bulky volume, and further increase the setting cost.
For these reason, how to upgrade the light collection efficiency of the solar collector device by modifying the structure design of the reflective plate 3 to further overcome the abovementioned drawbacks has become one of the important issues in this industry.
A reflective plate is used to collect sunlight rays in a conventional solar collector device, if an effective collecting width is increased, it would cause a height of the reflective plate to be rapidly increased, so as to restrict an elevation of light collection efficiency of the reflective plate. Accordingly, an embodiment of the instant disclosure provides a solar collector device to overcome the abovementioned problem.
In the embodiment of this instant disclosure, a light reflecting side of the reflective plate is composed of a plurality of reflective surfaces which are connected with each other. There are different inclination angles between each of the reflective surfaces and a light receiving surface of a light energy conversion unit, and each of the reflective surfaces can reflect and project the sunlight rays perpendicularly to the light receiving surface in an identical projection area of the reflective surface, so that the sunlight rays projected on the reflective surface would concentrate on the light receiving surface of the light energy conversion unit.
The solar collector device of the instant disclosure includes a light energy conversion unit and at least two reflecting devices. The light energy conversion unit can be a solar panel or a photothermal conversion device being used for a concentrated solar power (CSP) system. The light energy conversion unit has a light receiving surface. The two reflecting devices are respectively disposed at two opposite sides of the light receiving surface. The two reflecting devices respectively have a plurality of reflective surfaces which are connected with each other, wherein the reflective surfaces have different inclination angles between each of the reflective surfaces and the light receiving surface, and the relative inclination angle between each of the reflective surfaces and the light receiving surface ranges from 45 to 90 degrees. Each of the reflective surfaces respectively has different heights and different inclination angles, and the heights and the inclination angles of each of the reflective surfaces are arranged to let each of the reflective surfaces be able to reflect the sunlight rays in an identical projection area of the light receiving surface of the light energy conversion unit.
In the embodiment of this instant disclosure, in the plurality of reflective surfaces of each of the reflecting device, the reflective surface closest to the light receiving surface has a smallest inclination angle (but the inclination angle is larger than 45 degrees), the reflective surface remotest from the light receiving surface has a largest inclination angle (but the inclination angle of the last end of the reflective surface is smaller than 90 degrees), and the inclination angle of each of the reflective surfaces is smaller than the inclination angle between the reflective surface and the next reflective surface adjacent to the reflective surface.
This instant disclosure has an advantage in that, since the reflecting device is composed of the plurality of reflective surfaces having different inclination angles, the reflecting device of this instant disclosure can overcome the conventional reflective plate having the reflective surfaces with the same inclination angle, a width of top opening of the reflective plate is limited by the included angle between the reflective plate and the light receiving surface, and limitation of the width of light receiving surface of the light energy conversion unit, to achieve an increase of the width of the top opening of the reflective plate under the limited heights of the reflective plate, so as to increase an area of effective collecting area, and further enhance a light collection efficiency of the solar collector device.
In order to further appreciate the characteristics and technical contents of the instant disclosure, references are hereunder made to the detailed descriptions and appended drawings in connection with the instant disclosure. However, the appended drawings are merely shown for exemplary purposes, rather than being used to restrict the scope of the instant disclosure.
Embodiments disclosed in the instant disclosure are illustrated via specific examples as follows, and people familiar in the art may easily understand the advantages and efficacies of the instant disclosure by the disclosure of the specification. The instant disclosure may be implemented or applied by other different specific examples, and each of the details in the specification may be applied based on different views and may be modified and changed under the existence of the spirit of the instant disclosure. The figures in the instant disclosure are only for brief description, but they are not depicted according to actual size and do not reflect the actual size of the relevant structure. The following embodiments further illustrate related technologies of the instant disclosure in detail, but the scope of the instant disclosure is not limited herein.
Please refer to
For ease of explanation, the subsequent terms in the specification such as a height of the reflective surfaces 21, an inclination angle of the reflective surface 21, and a projection area of a reflective light are defined in the following paragraph. In this specification, the height of the reflective surfaces 21 is defined as, from a side perspective of the reflecting device 20, the distance between two endpoints which are generated from each of the different reflective surfaces 21 being along a direction perpendicular to the light receiving surface 11. The inclination angle of the reflective surface 21 is defined as, an included angle between each of the reflective surfaces 21 and the reference plane 12 disposed at the light receiving surface 11. The projection area is defined as, when the sunlight rays are perpendicular to the light receiving surface 11, and the sunlight rays are reflected by the reflective surface 21 to project onto the light receiving surface 11 to form a light projection range.
Each of the reflective surfaces 21 of the reflecting device 20 of this instant disclosure respectively has different heights and different inclination angles between each of the reflective surfaces 21 and the reference plane 12. The heights and the inclination angles of each of the reflective surfaces 21 are arranged to let each of the reflective surfaces 21 be able to cooperatively reflect the sunlight rays which are perpendicular to the light receiving surface 11 in an identical projection area of the light receiving surface 11 of the light energy conversion unit 10. Meanwhile, as shown in
Each of the reflective surfaces 21 of the reflecting device 20 of this instant disclosure is designed to have a rectangular plane with a width that is identical to the width of the light receiving surface 11, so that the sunlight rays reflected by each of the reflective surfaces 21 can form a rectangular projection area on the light receiving surface 11, and the sunlight rays reflected by each of the reflective surfaces 21 can be evenly distributed on the light receiving surface 11.
As shown in
A specific arrangement way of the reflective surface 21 of the reflecting device 20 of this instant disclosure is further described as follows. Please refer to
As shown in
Please refer to
Simultaneously, a light reflection path r1 indicated by an imaginary line in
The arrangement of the light reflection path of each of the reflective surfaces 21 of the reflecting device 20 in this instant disclosure is to let the sunlight rays reflected by each of the reflective surfaces 21 be projected on the identical projection area on the light receiving surface 11 together. Each of the reflective surfaces 21 should be avoid interfering in the light reflection path of another reflective surface 21 which is connected after the reflective surface 21. In the first embodiment of the instant disclosure, the projection area formed by the reflective light of each of the reflective surfaces 21 covers the whole area of the light receiving surface 11. In order to optimize the light reflection efficiency of each of the reflective surfaces 21, the inclination angle and height of each of the reflective surfaces 21 of this instant disclosure are adjusted to make the light traveling path reflected by the upper edge and the lower edge of each of the reflective surfaces 21 respectively pass through two side edges of the light receiving surface 11. For example, in the reflecting device 20 shown in
In addition, in order to avoid the sunlight rays reflected by each of the reflective surfaces 21 interfering with other reflective surfaces 21 to cause loss of the sunlight rays, the inclination angle of each of the reflective surfaces 21 in this instant disclosure has to be arranged so that, the inclination angle of each of the reflective surfaces 21 is equal to or smaller than the inclination angle of the light reflection path of the sunlight rays reflected by the another reflective surface 21 adjacent to each of the reflective surfaces 21 having the upper edge (shown in
Therefore, the arrangement of the inclination angle of each of the reflective surfaces 21 of the reflecting device 20 can be generalized as follows:
1. First, the inclination angle of each of the reflective surfaces 21 of the reflecting device 20 is in a range from 45 to 90 degrees.
2. In the plurality of reflective surfaces 21 of each of the reflecting device 20, the reflective surface 21 being most adjacent to the light receiving surface 11 has the smallest inclination angle (but the inclination angle is larger than 45 degrees), the reflective surface 21 remotest from the light receiving surface 11 has a largest inclination angle (but the inclination angle of the last end of the reflective surface is smaller than 90 degrees), and the inclination angle of each of the reflective surfaces 21 is smaller than the inclination angle between the reflective surface 21 and the next reflective surface 21 adjacent to the reflective surface 21.
3. In the plurality of reflective surfaces 21 of each of the reflecting device 20, the inclination angle of each of the reflective surfaces 21 is equal to or smaller than the inclination angle of the light reflection path of the next reflective surface 21 adjacent to the reflective surfaces 21.
The abovementioned connection is in accordance with the following relationship: αn<αn+1, αn≦θn+1, and 45°<α<90°, where the symbols have the following meanings:
α represents the relative inclination angle between each of the reflective surfaces 20 and the reference plane 12;
θ represents the relative inclination angle between the light reflection path generated by the sunlight rays projecting on each of the reflective surfaces 21 and the reference plane 12;
n represents an order of an arrangement in a direction from each of the reflective surfaces 21 in the reflecting device 20 close to the light receiving surface 11 away from the light receiving surface 11, and n is a positive integer which is larger than or equal to 1 and smaller than total amount of the reflective surfaces 21 in each of the reflecting devices 20.
The technical principle of arrangement of the inclination angle and the height of each of the reflective surfaces 21 of the reflecting device 20 can be understood from
The solar collector device of the first embodiment is composed of the four reflecting devices 20 which are respectively disposed at two opposite sides of the light energy conversion unit 10. Therefore, the light collection efficiency with two axes can be provided, and it can be cooperatively used with a biaxial tracking system (which is two axials of pitch and rotation).
Please refer to
The height of the second reflecting device 20B in the second embodiment is lower than the height of the first reflecting device 20A, and is adapted for a single-axis tracking system, or for a small power station being located in a metropolis having high cost of land. The biaxial tracking system also can be cooperatively used with the first and second reflecting devices 20A, 20B of the second embodiment depending on limitations of shapes and sizes of a place, so as to achieve the maximum power output.
Please refer to
The reflecting device 20 of the third embodiment can be only disposed at the two sides of the light energy conversion unit 10, and the light receiving surface 11 of the light energy conversion unit 10 has the light collecting efficiency with only one direction. Thus, the reflecting device 20 of the third embodiment can be cooperatively used with the single-axis tracking system, or the reflecting device 20 also can be aligned along a north-south direction and fixed for not tracking the sunlight. In addition, as shown in
Please refer to
The reflecting device 20 of the fourth embodiment is manufactured using a different method, but the fundamentals and functions in the fourth embodiment are the same as the abovementioned fundamentals and functions of the reflecting device. The technical means of these embodiments can be used in combination.
Please refer to
The different reflecting devices 20 of the solar collector device in this embodiment can be utilized to respectively cover the different areas of the light receiving surface 11 of the light energy conversion unit 10, so as to meet the light collecting efficiency. By this way, the light intensity entering into each of the areas of the light receiving surface 11 of the light energy conversion unit 10 is more even.
In this embodiment, the inclination angle and height of each of the reflective surfaces 21 of the reflecting device 20 of the solar collector device in this instant disclosure can be further arranged to let each of the reflective surfaces 21 respectively reflect the sunlight rays in the different projection areas on the light receiving surface 11 of the light energy conversion unit 10. The projection area formed by each of the reflective surfaces 21 can cooperatively cover the whole area of the light receiving surface 11. That is to say, the light receiving surface 11 can be divided into a plurality of projection areas, the height and inclination angle of each of the reflective surfaces 21 are respectively arranged to be able to project the sunlight rays in each of the different areas, such that the reflective light of the reflecting device 20 can evenly project in every corner on the light receiving surface 11, or the projection area formed by the reflective light of each of the reflective surfaces 21 can be partly overlapped, so as to locally increase the amount of receiving light by the light receiving surface 11.
Please refer to
In this embodiment, the reflecting device 20 is respectively aligned and disposed at four sides of the light receiving surface 11 of the light energy conversion unit 10, when each of the reflecting devices 20 is observed by a plan view, that is represented a cross shape. An auxiliary collector device 40 is further disposed in a gap between each of the two adjacent reflecting devices 20 in this embodiment. The auxiliary collector device 40 of this embodiment is an arc-shaped reflector connected between two adjacent sides of the two adjacent reflecting devices 20. A cross-sectional shape of the reflector of the auxiliary collector device 40 has an arc-curve, and the reflector of each of the auxiliary collector devices 40 has a certain inclination angle that the sunlight rays can be reflected to project on the light receiving surface 11 of the light energy conversion unit 10 by a certain inclination angle. The sunlight rays not in the area covered by the reflecting device 20 can be reflected onto the light receiving surface 11 of the light energy conversion unit 10 via the auxiliary collector device 40, so as to upgrade the overall amount of receiving light.
Please refer to
This instant disclosure has advantages in that, since the reflecting device is composed of the plurality of reflective surfaces having different inclination angles, the reflecting device of this instant disclosure can overcome the conventional reflective plate having the reflective surfaces with the same inclination angle, a width of the top opening of the reflective plate is limited by the included angle between the reflective plate and the light receiving surface, and limitation of the width of light receiving surface of the light energy conversion unit, to achieve an increase of the width of the top opening of the reflective plate under the limited heights of reflective plate, so as to increase an area of effective collecting area, and further enhance a light collection efficiency of the solar collector device.
The descriptions illustrated supra set forth simply the preferred embodiments of the instant disclosure; however, the characteristics of the instant disclosure are by no means restricted thereto. All changes, alterations, or modifications conveniently considered by those skilled in the art are deemed to be encompassed within the scope of the instant disclosure delineated by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 103222862 | Dec 2014 | TW | national |