2020 can be a very important year for Tesla Solar. Last year, Tesla presented solar roof, and also announced its expansion in Israel.
During Tesla’s Q3 conference call, Elon Musk said that he thinks Tesla’s solar segment could be as big or even bigger than the company’s automotive business. He also said that Tesla’s resources were mainly focused on the production of Model 3 in the past few years. However, since everything looks stable now, he wants to focus on the solar segment of Tesla.
Today, the company has a number of products that can help the world switch to renewable energy. Solar panels and roofs, energy storage systems and electric cars can make us independent of fossil energy sources. All of these “helpers” were developed by Tesla over the years. The company continues to work to improve its products, as evidenced by its new patents.
Solar tiles, in addition to its direct functions, must correspond to other parameters. One of these parameters is the aesthetic appearance. Tesla strives to make your roof not only functional, but also beautiful. Tesla filed a patent application on July 2, 2018, and it was published on January 2, 2020. This patent relates to a photovoltaic tile that has a uniform color appearance.
Photovoltaic modules, also called PVs or solar panels, which can include a two-dimensional array of solar cells, are usually installed on roofs of buildings. But the photovoltaic tile (or solar tile) can be a special type of photovoltaic module that provides weather protection for the home and a pleasant aesthetic appearance, and also functions as a photovoltaic module for converting solar energy into electricity. The photovoltaic tile may be in the form of a conventional tile and may include one or more solar cells enclosed between the front cover and the back cover, but typically contains less solar cells than conventional solar panels.
Source: Tesla patent/ Shows an exemplary configuration of PV roof tiles on a house. PV roof tiles 100 can be installed on a house like conventional roof tiles or shingles. Particularly, a PV roof tile can be placed with other tiles in such a way as to prevent water from entering the building
The front and back covers can be made of reinforced glass or other material that protects the solar cells from weathering. To ensure sufficient sunlight transmission, the front cover must be transparent, while encapsulated photovoltaic structures are often dark in color. If viewed from a shallow angle angle, for example, if you look at the roof from the street, dark photovoltaic structures can become visible. Then the color contrast between the photovoltaic structures and the glass lid may have an unaesthetic appearance.
One embodiment can provide a photovoltaic roof tile. The photovoltaic roof tile can include a transparent front cover, a back cover, a plurality of photovoltaic structures positioned between the front cover and the back cover, and a front-cover-colorant layer positioned on an interior surface of the transparent front cover that faces a top surface of the photovoltaic structures. A color of the front-cover-colorant layer can substantially match a color of the top surface of the photovoltaic structures, and the front-cover-colorant layer can be configured to cover regions of the interior surface that are not directly above the top surface of the photovoltaic structures, thereby enabling a substantially uniform appearance of the photovoltaic roof tile.
In a variation on this embodiment, a respective photovoltaic structure can include a first edge busbar positioned near an edge of a first surface and a second edge busbar positioned near an opposite edge of a second surface, and the plurality of photovoltaic structures can be arranged in such a way that the first edge busbar of a first photovoltaic structure overlaps the second edge busbar of an adjacent photovoltaic structure, thereby resulting in the plurality of photovoltaic structures forming a serially coupled string.
In other versions it can:
- the photovoltaic tile may further include an external conductive connector connected to the bus with the open edge of the string connected in series;
- an external conductive connector may be located under the dye layer of the front cover, so that it will be out of sight when viewed from the outside of the transparent front cover;
- the transparent front cover may include glass;
- the front-cover-colorant layer can include a layer of glass frit;
- the interior surface of the transparent glass cover can be textured;
- the back cover can include glass, and the photovoltaic roof tile can further include a back-cover-colorant layer positioned on a surface of the back cover;
- the back-cover-colorant layer can be configured to completely cover the surface of the back cover;
- the back-cover-colorant layer can be configured to cover border regions of the surface of the back cover.
The fabrication method can include obtaining a front cover and a back cover, forming a cascaded string of photovoltaic structures, and laminating the cascaded string of photovoltaic structures between the front cover and the back cover. The front cover can include a transparent glass sheet and a front-cover-colorant layer positioned on an interior surface of the front cover. A color of the front-cover-colorant layer can substantially match a color of a top surface of the cascaded string, and the front-cover-colorant layer can be configured to cover regions of the interior surface that are not directly above the top surface of the cascaded string, thereby enabling a substantially uniform appearance of the photovoltaic roof tile.
Embodiments of the invention solve at least the technical problem of color management of solar roof tiles.
FIG. 5B illustrates the side view of the string of cascaded strips, according to one embodiment. In the example shown in FIGS. 5A and 5B, the strips can be segments of a six-inch square or pseudo-square solar cell, with each strip having a dimension of approximately two inches by six inches. To reduce shading, the overlapping between adjacent strips should be kept as small as possible. Therefore, in the example shown in FIGS. 5A and 5B, the single busbars (both at the top and the bottom surfaces) can be placed at or near the very edge of the strip. The same cascaded pattern can extend along multiple strips to form a serially connected string, and a number of strings can be coupled in series or parallel.
About the Author
Eva Fox joined Tesmanian in 2019 to cover breaking news as an automotive journalist. The main topics that she covers are clean energy and electric vehicles. As a journalist, Eva is specialized in Tesla and topics related to the work and development of the company.