JPH10227102A - Glass for solar cell roof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the inharmony in the design and massive feeling of a roof with built-in solar cells and improve the feeling of one united body between the solar cells and the roofing material built with the solar cells by using colored glass with a specified transmittance for visual light having reflecting preventing ability on the surface which is used as a roofing material for the portion other than the solar cells. SOLUTION: On a roof with built-in solar cells, colored glass having the transmittance of 5 to 70%, or more desired to be 10 to 50% and also having reflection preventive ability by roughening its surface or applying a reflection preventing coat is used as a roofing material other than the solar cell. That is, the colored glass used together with the solar cells should be architectural colored glass with a dark gray color. In conformity with the tone of the solar cell portion, both the transmittance and reflective characteristics of the visual light should be considered for selection and adjustment. Or a colored coating comprising a single to combined metal or metal oxides or a colored coating of inorganic-based paint should be formed on the surface of transparent glass and desired tone and the transmittance of visual light should be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to glass for solar cell roofs.

[0002]

2. Description of the Related Art For roofs of buildings, clay tiles, slate, new-generation tiles and metal roofing materials are generally used as general-purpose roofing materials. Glass tiles are also known as applications for daylighting. However, the above-mentioned general-purpose roofing materials have problems such as breakage, weathering, and corrosion, and it is said that it is difficult to endure the same to the life of a building. It is expected that the roof with solar cells will spread or increase in the future, but since the outside of the solar cells is usually covered with highly transparent glass, the color of the solar cells themselves is reflected and reflected in appearance. Because of the different characteristics, it is difficult for conventional roofing materials to achieve a sense of unity due to differences in design and texture. As a glass roofing material, for example, there is Japanese Patent Publication No. 3-337. However, since it is a colorless and transparent glass tile having a visible light transmittance of more than 70% for daylighting, there is also a sense of incongruity.

[0003]

SUMMARY OF THE INVENTION The present invention has been made for the purpose of solving the above-mentioned problems of the conventional roofing material. More specifically, the present invention relates to a conventional roof having a solar cell incorporated in a part thereof. It is an object to eliminate or improve disharmony between a battery portion and a portion other than a solar cell, and to provide a durable and safe glass roofing material as a roofing material for a portion other than a solar cell.

[0004]

According to the present invention, there is provided a roof glass having a visible light transmittance of 5 to 70% and having a surface having an antireflection property, as a roof material other than a solar cell. provide. The present invention also provides a glass for roof using a safety glass such as a tempered glass, a netted glass, a lined glass and a laminated glass as the colored glass.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The colored glass used in the present invention has a visible light transmittance of 5 to 70%, preferably 10 to 5%.
0% colored glass is used. Being a colored glass is important in achieving color harmony with the solar cell part. Since the roof of the solar cell part has a dark color unique to the solar cell, for example, gray or blue, it is desirable that the colored glass shared with the solar cell part be as close as possible to the color tone of the solar cell.

In order to obtain the colored glass, there are a method of coloring the glass itself and a method of forming a colored layer on the surface of the transparent glass by surface treatment. Representative examples of the former include architectural color glasses such as dark gray glass, green glass, brown glass, and bronze glass, and any of these may be selected according to the color tone of the solar cell portion. Then, in order to harmonize the solar cell with the solar cell part so as not to cause any unpleasant sensation, the selection is adjusted in consideration of the visible light transmittance and the reflection characteristics.

On the other hand, in the latter, a colored film composed of a metal or a metal oxide alone or a combination thereof, or a colored film of an inorganic paint is formed on the surface of ordinary transparent glass to obtain a desired color tone and visible light. Obtain the transmittance. Such a colored coating has an advantage that the color tone can be easily adjusted to the solar cell portion. In addition, although a colorless transparent glass is usually used as the transparent glass, a light-colored transparent glass may be used.

Further, when the appearance of the solar cell portion has a pattern, a desired pattern similar to the pattern can be formed by the colored coating. The roof of the solar cell part is composed of a plurality of solar cell panels, and each panel has a plurality of unit solar cells arranged in parallel on a single board. The appearance has these arrangement patterns. Therefore, when obtaining colored glass by surface treatment, an attempt is made to form a similar or similar pattern similar to this pattern with a coating film. In this case, the visible light transmittance varies slightly depending on the position due to the pattern, and is therefore treated as an average value of the entire panel.

The limitation of the visible light transmittance has a significance in giving a degree of freedom in harmony with a solar cell portion. If the visible light transmittance exceeds 70%, it becomes close to ordinary colorless and transparent glass, so that it is difficult to harmonize with the solar cell portion and obtain an integral structure with little uncomfortable feeling.

On the other hand, if the visible light transmittance is less than 5%, the color becomes almost black or dark, so that an adjustment function for matching the solar cell portion cannot be obtained, and conversely, it works to increase the sense of discomfort. For this reason,
The range of the visible light transmittance is suitably from 5 to 70%, and considering the color tone of the solar cell part which is put into practical use, it is from 10 to 5%.
A range of 0% is more preferable.

In the present invention, these colored glasses may be used as they are, but are usually used in the form of safety glass from the viewpoint of safety. Examples of the safety glass include tempered glass, netted glass, lined glass, and laminated glass. Among them, tempered glass is preferred in terms of safety and cost.

Further, the roof glass of the present invention has an antireflective surface. The surface properties of the glass are effective elements for achieving integrated harmony with the solar cell portion. In particular, in a state where sunlight is received, the surface of the roof glass becomes a mirror surface and reflection occurs, so that the reflectance of the roof glass is equal to or less than the reflectance of the solar cell part.

As the antireflection means for the glass, generally known methods such as surface roughening or an antireflection film can be appropriately used. However, since it is necessary to manufacture a building material at low cost, the following method of mechanically or chemically processing or treating a glass surface to make it rough is usually employed.

The mechanical method is to form fine irregularities on the surface of the glass at the same time as the glass is formed, or to grind or sandblast the surface of the glass to give desired irregularities, and reduce the reflection by its scattering effect. Things. On the other hand, the chemical method is etching, and may be performed after roughening the surface by the mechanical method described above. The antireflection can be performed only on one side of the glass or on both sides.
Further, in order to improve the flow of rainwater irrespective of antireflection, a vertical streak groove may be provided on the outer surface of the glass.

[0015]

【Example】

Example 1 A roll formed by engraving fine irregularities by sandblasting is used as a lower forming roll of a roll-out method forming apparatus, and a colored glass substrate is roll-press-formed to have a visible light transmittance of 20% and a surface of about 120 μm. A colored glass having irregularities was obtained. This glass is gray in appearance,
The reflection on the surface was slight due to the scattering effect due to the unevenness described above, and when used on a portion of the solar cell roof other than the solar cell, the solar cell portion was in harmony with the aesthetic appearance.

Example 2 After the colored gray glass formed by the float method was rubbed and polished in the polishing plate process, the polished surface was polished and polished with a polisher. This colored glass had a visible light transmittance of 20%, and a ground glass having irregularities of 1 to 5 μm on the surface was obtained. When this colored glass was used by incorporating it into a part of a solar cell roof in the same manner as in Example 1, an appearance having a sense of unity with the solar cell part was obtained.

Example 3 The colored glass of Example 2 molded by the float method was subjected to sandblasting to give a rough surface to the surface, a liquid storage wall was provided around the glass, and a hydrofluoric acid solution was passed over the surface to shake the glass. While moving, it was held for 2 minutes for etching. Although the etched colored glass had a visible light transmittance of 18% and a surface irregularity of about 100 μm, it had a calm reflection characteristic, and became more harmonious with the solar cell part.

Example 4 One surface of a transparent ordinary plate glass was etched with a hydrofluoric acid solution to form an irregular surface of about 3 μm, and a coating of an inorganic paint was formed on the other surface of the glass. A 10% gray colored glass was obtained. When this glass was subjected to a tempering treatment of about half of normal tempering to obtain a semi-tempered glass, and then used as a roofing material, it was confirmed that the glass was a roof glass excellent in appearance and strength.

Example 5 A printing screen in which a pattern of a crystalline solar cell panel was made was prepared and printed on the smooth surface side of a transparent, non-glare-shaped template glass using a blue / gray inorganic ink with this screen. After that, a normal tempering treatment was performed to obtain a tempered glass approximating the design or pattern of the solar cell panel. The average visible light transmittance of this glass was about 30%.

When this glass was used as a roof glass for a portion of the solar cell roof other than the solar cell, the roof material became very harmonious with the solar cell portion, and a roof with high integrity was obtained.

[0021]

The roof glass of the present invention is highly integrated with the solar cell roof in both design and texture as a roof material for portions other than the solar cells of the solar cell roof. In addition, it is a durable roofing material without problems such as weathering and corrosion, and if used in the form of safety glass, there is no worry about cracking etc.
Excellent safety.

Claims (3)

[Claims] 1. A solar cell roof glass comprising a colored glass having a visible light transmittance of 5 to 70% and having a surface having antireflection properties. 2. The glass for a solar cell roof according to claim 1, wherein the colored glass is a safety glass such as a tempered glass, a netted glass, a lined glass and a laminated glass. 3. The glass for a solar cell roof according to claim 1, wherein the colored glass has a colored coating having a pattern similar to a pattern of a solar cell portion.