JPS60235442A - Photovoltaic unit - Google Patents

Abstract

PURPOSE:To enable a solar cell panel to easily thaw and remove any snow covering the cell, by providing photovoltaic elements with means for supplying electric current in the forward direction thereof. CONSTITUTION:A solar cell panel 1 is composed of a multiplicity of photovoltaic elements 11 which are connected in parallel such that the anode of each photovoltaic element 11 is coupled to the cathode of the adjacent cell 11. The cathode- side end of the cells as a whole is connected to the negative electrode of a storage battery 2 while the anode-side end is coupled to the positive electrode thereof through a control circuit interposed therebetween. The control circuit 3 controls the direction of current flow such that if the solar cell panel 1 is covered with snow, electricity is supplied from the storage battery 2 to the solar cell panel 1 in the direction from the anode side to the cathode side, namely in the forward direction thereof, so as to cause each photovoltaic element 11 to generate heat by utilizing its internal resistance and to thaw and remove the layer of snow.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photovoltaic device with a heat generating function.

[Prior art]

2. Description of the Related Art Various photovoltaic devices, so-called solar cells, that directly convert light energy into electrical energy have been proposed and used.

By the way, this type of solar cell is normally installed outdoors, but if it snows, for example, the snow on the solar cell blocks the sunlight, causing the solar cell to stop functioning. had the problem of being forced to carry out frequent snow removal work.

〔the purpose〕

The present invention was made in view of the above circumstances, and its purpose is to generate heat by applying electricity to the photovoltaic element using the internal resistance of the photovoltaic element itself, and to absorb the heat. To provide a photovoltaic device which can melt snow and easily remove snow, making manual snow removal unnecessary and achieving significant labor savings.

〔composition〕

A photovoltaic device according to the present invention is characterized by comprising a photovoltaic element and means for passing current through the element in the forward direction.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof. FIG. 1 specifically explains a photovoltaic device according to the present invention (hereinafter referred to as the device of the present invention) based on an embodiment shown in the drawings.

FIG. 1 is a schematic circuit diagram of a photovoltaic device according to the present invention, in which 1 indicates a solar cell panel, 2 a storage battery, and 3 a control circuit.

The solar cell panel 1 is constructed by connecting a large number of photovoltaic elements 11 in series by sequentially connecting the anodes to the cathodes of adjacent photovoltaic elements 11, and the cathode side end of the solar panel 1 as a whole is connected to a storage battery. One pole of the storage battery 2 and the anode side end thereof are connected to the soil of the storage battery 2 with a control circuit 3 interposed in the middle.

When the solar panel 1 is illuminated by the sun, the control circuit 3 transfers the current generated in the solar panel 1 to the storage battery 2.
If there is snow on the solar cell panel 1, electricity is passed from the storage battery 2 to the solar cell panel 1 from the anode side to the cathode side, that is, in the forward direction. The internal resistance of each photovoltaic element 11 is used to generate heat, and the direction of current flow is controlled so as to melt and remove snow accumulation.

Note that during the daytime in winter, the power generation amount of the solar panel 1 is checked, and when the power generation amount decreases, this is detected, and when it is determined that there is snow, the control circuit 3 automatically energizes the solar cell panel 1. You can.

The current value to be applied may be determined appropriately by taking into account the area of the solar panel 1, the amount of snowfall, etc.

[Numerical example]

As shown in FIG. 2, a transparent electrode 21, an amorphous silicon layer 22, and a back electrode 23 are formed on the main surface of a transparent glass substrate 20.
A plurality of amorphous silicon photovoltaic elements (cells) formed by laminating the above in this order are sequentially connected to the transparent electrode 21 and back electrode 23 of each adjacent photovoltaic element, and the whole is connected in series. An amorphous silicon solar cell module (integrated 9-stage cell: 10 Zheng angle) is configured, and a current of 0.5 A is applied in the forward direction, that is, from the anode side to the cathode side.
When the current was passed (to 5.5 m/C), the surface of the photovoltaic element could be heated to form a difference of about 20° C. with respect to the outside temperature.

Further, when a current of 1.08 (110 mA/cJ) was passed in the forward direction through the amorphous silicon solar cell, the surface of the photovoltaic element was heated to form a difference of about 40°C from the outside temperature. was completed. Furthermore, the amorphous silicon solar cell described above was installed on the ground, and as a result of passing 1 ffl of current in the forward direction of 0.5, 10 cH was generated around it.
1, but there was no snow on the solar cells at all.

Although the above description is an example of an amorphous silicon solar cell, it goes without saying that a single crystal Si solar cell may also be used.

FIG. 3 is a graph showing the current-voltage characteristics of amorphous silicon solar cells and single-crystal silicon solar cells, with the horizontal axis representing voltage (V) and the vertical axis representing current (Acm).
-2) is shown.

The solid line in the graph shows the characteristics of single-crystal silicon solar cells, and the broken line shows the characteristics of amorphous silicon solar cells. As is clear from this graph, for example, when a current of 0.1 A/c is passed through, the voltage is 0.6 V for a small crystal silicon solar cell, and 1.2 V for an amorphous silicon solar cell. Therefore, the amount of heat generated by an amorphous silicon solar cell is twice that of a single crystal silicon solar cell, and it can be seen that an amorphous silicon solar cell can generate heat more efficiently, but in either case, a sufficient heat generation effect is obtained. It is clear that

Although the above-mentioned embodiments have been described with reference to the case where solar cells are configured as panels, it goes without saying that the present invention can also be applied to roof tiles with solar cells in which solar cells are provided on roof tiles.

〔effect〕

As described above, since the device of the present invention is equipped with a means for passing current through the photovoltaic element in the forward direction, it is possible to cause the photovoltaic element to generate heat at any time by passing this current. This makes it possible to use solar cells even in the winter, especially in snowy areas where solar cells may be cut off due to snowfall, improving efficiency, and eliminating the need for snow removal labor, resulting in significant labor savings. The present invention has excellent effects such as being able to achieve the following.

[Brief explanation of the drawing]

Fig. 1 is a schematic circuit diagram of the device of the present invention, Fig. 2 is a cross-sectional structural diagram showing the general configuration of an amorphous silicon solar cell module, and Fig. 3 is a current flow between an amorphous silicon solar cell and a single crystal silicon solar cell. It is a graph showing voltage characteristics. 1...Solar cell panel 2...Storage battery 3...Control circuit 20...Glass substrate 21...Transparent electrode
22...Amorphous silicon layer 23...Back electrode time Applicant Sanyo Electric Co., Ltd. Agent Patent Attorney Norio Kono/l No. 1 Former No. 2 Fig. 1 [ 1 ( [^ Voltage (V)] Fig. 3

Claims (1)

[Claims] 1. A photovoltaic device comprising a photovoltaic element and means for passing current through the element in the forward direction. 2. The photovoltaic device according to claim 1, wherein the photovoltaic element is an amorphous semiconductor.