WO2020065060A1

WO2020065060A1 - Expanded pv system with improved efficiency

Info

Publication number: WO2020065060A1
Application number: PCT/EP2019/076294
Authority: WO
Inventors: Maximilian Fleischer; Roland Pohle; Jürgen SCHÖNHUT; Elfriede Simon; Ulrich WÖHRL; Oliver von Sicard
Original assignee: Siemens Aktiengesellschaft
Priority date: 2018-09-28
Filing date: 2019-09-27
Publication date: 2020-04-02
Also published as: DE102018216768A1

Abstract

The invention relates to the improving the efficiency of an already existing, installed PV system, wherein a film-like, laminated perovskite PV cell, if appropriate in addition to the associated power electronics unit, is added to an existing PV cell of the existing PV system and is arranged on the existing PV cell in such a way that light L from a light source, which is to be converted into electrical energy by the existing PV system, initially falls onto the perovskite PV cell and subsequently falls onto the existing PV cell. Thus a laminated perovskite PV cell is used in such a way that an existing PV system is upgraded such that the efficiency thereof is improved without replacement of components.

Description

description

Extended PV system with improved efficiency

The invention relates to a photovoltaic device and in particular to the retrofitting of such a PV device.

Solar power generation with the means of photovoltaics (PV) is contributing to a rapidly increasing share of electricity production in Central Europe for environmental and increasingly economic reasons, for example. A large number of PV systems have already been installed worldwide, which are mainly based on conventional approaches with silicon-based PV cells. For some years now, so-called Perovskite materials such as CH3NH3PbI3 (or more generally (CH3NH3) MX3- xYx (with M = Pb or Sn as well as X, Y = I, Br or Ci)) with regard to their use in PV cells, which, due to their optoelectronic properties, enables a highly efficient conversion of electromagnetic radiation energy allow in electrical energy.

The widespread silicon-based PV cells typically have efficiencies in the order of 15-20%, although typical age-related performance reductions of around 0.5% per year can be expected. Correspondingly, such installed conventional, i.e. silicon-based PV systems predict that efficiency will be so low in the foreseeable future that it will hardly be economically viable.

The efficiencies currently achievable with perovskite-based PV cells are> 22%. Although this comparatively high value currently applies to laboratory conditions, further improvements in the stability of the material and upscaling from the respective cell to module size can be expected very soon, so that such perovskite-based PV cells become competitive with the conventional silicon-based cells. It can therefore be expected that perovskite-based PV systems will be selected for new installations. The most economical use of perovskite PV technology can be achieved, for example, as described in WO 2018162496 A1 with a tandem PV module consisting of a conventional silicon PV cell and a perovskite PV cell. This tandem PV module has two PV cells of different types which are arranged one on top of the other, ie one of the PV cells is a silicon-based cell, while the other PV cell is perovskite-based. The different cell types, i.e. silicon-based or perovskite-based, differ in the underlying material and consequently in their spectral sensitivity, i.e. different cell types have their respective maximum efficiency for different spectral ranges of sunlight. The perovskite PV cell arranged above and facing the sun makes optimal use of the higher energy component of the light, the silicon cell below uses the remaining, comparatively low-energy component of the light, which passes the perovskite cell unhindered for the most part. As a result, the tandem cell group as a whole offers high efficiency for a broader spectral range. This means that efficiencies in the order of> 30% are possible for the silicon perovskite tandem PV cell described, whereas conventional silicon PV cells nowadays typically offer efficiencies in the order of -20%.

When installing a new PV system, the perovskite technology can be used without any special effort, thus achieving the above-mentioned advantage of high efficiency. However, if one looks at the large number of installed, conventional and still functional PV systems, it can be seen that, despite the efficiency improvement that can be achieved, a complete replacement of the installed PV system by a perovskite-based PV system is generally not very economical as long as this conventional system works with at least sufficient efficiency. There with perovskite PV technology, however, a technology with higher efficiency is available, it is particularly desirable for use on already installed, conventional PV systems to use the advantageous technology here and to improve the efficiency of the existing systems.

It is therefore an object of the present invention to provide a way to improve the efficiency of an existing, conventional PV system.

This object is achieved by the supplementary device described in claim 1 and its use according to claim 5 as well as by the extended PV system according to claim 6 and a method for improving the efficiency of an existing PV system according to claim 12. The subclaims describe advantageous refinements.

A PV system supplementary device is proposed for supplementing an existing PV system, the PV system comprising an existing PV cell of a first cell type. The PV system supplementary device comprises a perovskite PV cell with a flat, perovskite-based light-sensitive component, the light-sensitive component having a first surface and a second surface opposite the first surface, with the first and the second Surface is each a lamination brought up, so that the light-sensitive component is completely enclosed by the laminations, so that the light-sensitive component is protected against dirt and moisture. The perovskite PV cell is dimensioned such that it can be attached to a surface of the existing PV cell of the existing PV system.

The PV system supplementary device therefore represents an upgrade for the existing PV system. An “existing” PV system is understood here to mean a PV system which, when the supplementary device was added, at the time is already installed at their place of use. Another limitation can be that this existing PV system has already fulfilled its intended purpose, i.e. was already in regular operation. The "regular" operation should differ in particular from a test operation, which is undertaken, for example, when the PV system is installed and possibly tested before regular operation is started for the first time.

The term "areal" means that the dimensioning of the areal component in the Cartesian x, y and z coordinates is chosen such that extensions in the vertical z direction are negligible compared to the horizontal extensions in the x and y directions .

The invention is based on the assumption that tandem PV modules, in which two or even more light-sensitive PV cells or layers are typically arranged one above the other, are to be used to achieve a high efficiency of a respective PV system. Furthermore, it is assumed that the aim should be that existing, ie already installed PV systems should continue to be used, so that an exchange of old, already installed PV systems should be avoided as far as possible. It is therefore proposed to upgrade already installed PV systems with the greatest possible reuse of the already installed components in tandem PV cells. An upgrade is proposed for the corresponding conversion, which includes in particular a perovskite PV cell that can be applied to the existing conventional PV cell. It is therefore possible to use both the area already used, e.g. roofs or land, as well as many parts of the system already installed, e.g. network connections, electricity meters, mounting brackets and official permits, with greater efficiency. The lamination means that the perovskite PV cell is protected against dirt and moisture and that the perovskite PV cell, which is designed in the form of a film, is easy to handle. The perovskite PV cell of the PV system supplementary device has a holder with which the perovskite PV cell can be attached to the existing PV cell in such a way that it is fixed in space to the existing PV cell and that light L from a light source first falls on the perovskite PV cell, crosses it and then falls on the existing PV cell.

The PV system supplementary device can additionally comprise a power electronics unit which is assigned to the perovskite PV cell and which, if necessary, converts an electrical voltage U20 provided by the perovskite PV cell when illuminated with the light L into an at an output of the Additional power electronics unit converts electrical voltage to be provided U21 and which has a connection with which it can be connected to an existing power electronics and / or an existing control unit of the existing PV system.

The PV system supplementary device can further comprise a separate control unit with which the additional power electronics unit can be regulated and which can be connected to the existing control unit of the existing PV system, so that data can be exchanged between the separate control unit and the existing control unit . The data exchange can also include, for example, control signals with which the existing control unit can regulate or control the separate control unit.

It is therefore the special use of a

Perovskite PV cell, which has a perovskite-based light-sensitive component, which is enclosed by means of a lamination, so that the light-sensitive component is protected from dirt and moisture, for improving the efficiency of an existing PV system by means of the PV described above System supplementary facility beat. The use of this PV system supplementary device essentially consists in adding the perovskite PV cell of the supplementary device to an existing PV cell of the existing PV system, so that the

Perovskite PV cell is integrated into the PV system in addition to the existing PPV cell and an electrical voltage generated with the perovskite PV cell is supplied to the existing PV system. An important point here is that the perovskite PV cell is added or supplemented to the existing PV cell, which is expressly different from the fact that the existing PV cell is replaced by a perovskite PV cell.

An extended PV system to provide

Electrical voltage when the extended PV system is illuminated with light L from a light source, accordingly comprises an existing PV system which comprises at least one existing PV cell of a first cell type, for example a silicon-based PV cell, a subsequently installed PV -Supplementary device with a laminated perovskite PV cell. The term "retrospectively", like the term "existing", is aimed at the fact that a PV system already exists and is in operation and that the supplementary device is only added later, i.e. subsequently.

The expanded PV system ultimately includes the existing PV cell and the added perovskite PV cell, which is attached to the existing PV cell with a suitable holder in such a way that the light L first of all affects the light-sensitive component of the perovskite PV cell and then falls on the light-sensitive component of the existing PV cell. Since the efficiency maxima of the two PV cells are typically in different wavelength ranges, this arrangement can ensure that, despite the absorbing influence of the PV cell arranged above, an overall increased efficiency is achieved if the upper cell is transparent to the wavelength range , in which the effi ciency maximum of the lower cell lies. The holder for fastening the perovskite PV cell to the existing PV cell can be an at least partially transparent adhesive, the perovskite PV cell being glued to the surface of the existing PV cell by means of the adhesive through which the light L from the light source falls on a light-sensitive component of the existing PV cell. The adhesive is transparent at least for that sub-spectrum of the light L which comprises the spectral range for which the lower, first PV cell or its light-sensitive component has its maximum efficiency. As already indicated, this means that the PV system as a whole has a higher efficiency, since both individual cells of the tandem PV cell formed in this way can work at their respective maximum effi ciency.

Alternatively, the holder for attaching the perovskite PV cell to the existing PV cell can comprise a clamp with which the perovskite PV cell can be attached to the existing PV cell. This allows a very simple and easy to carry out attachment.

The extended PV system and in particular its PV system supplementary device comprises a separate power electronics unit which is assigned to the perovskite PV cell and which, if necessary, provides an electrical voltage U20 provided by the perovskite PV cell when illuminated with the light L. converts into an electrical voltage U21 to be provided at an output of the separate power electronics unit. Advantageously, the separate power electronics unit also has a connection with which it can be connected to existing power electronics and / or an existing control unit of the existing PV system.

It is therefore not used in this version, the power electronics unit of the existing PV system for the newly installed perovskite PV cell. The use of a separate power electronics unit for the perovskite PV Cell allows the perovskite PV cell to be operated at its optimal working point. The same applies accordingly to the existing PV cell.

The existing PV system of the extended PV system has an existing power electronics unit which is assigned to the existing PV cell and which, if necessary, converts an electrical voltage U10 provided by the existing PV cell when illuminated with the light L into one at a time Converts electrical voltage Ull to be provided from the output of the existing power electronics unit, the existing power electronics unit being controllable by an existing control unit of the existing PV system.

The supplemented separate power electronics unit of the

Perovskite PV cell in turn has a connection via which it can be connected to the existing power electronics and / or to the existing control unit of the existing PV system and can also be controlled by the existing control unit. The existing power electronics unit and the separate power electronics unit of the perovskite PV cell can therefore be operated independently of one another with the help of the existing control unit, so that both can work at their respective optimal working point.

As part of a method for improving the efficiency of an existing PV system or for producing an improved PV system, a perovskite PV cell is added to an existing PV cell of the existing PV system and is thereby arranged on the existing PV cell or attached that light L from a light source, which is to be converted into electrical energy by the existing PV system, first on the perovskite PV cell and then, after crossing the perovskite PV cell, on the existing PV cell falls, with the respective PV cell interacting with the light falling on it in a known manner providing an electrical voltage or electrical energy. To produce the perovskite PV cell to be added, a flat, perovskite-based light-sensitive component is laminated, the light-sensitive component being enclosed by lamination layers in such a way that the light-sensitive component is protected against dirt and moisture. Before the lamination, the light-sensitive component is of course provided with corresponding electrical connections via which an electrical voltage generated when the light-sensitive component is illuminated with light L can be tapped off.

The dimensioning of the perovskite PV cell to be added is adapted to the dimensioning of the existing PV cell, with in particular the horizontal extensions of the lamination layers in the x and y directions and the corresponding horizontal extensions of a carrier of the existing PV cell , in which the light-sensitive component of the existing PV cell is embedded, largely correspond to each other.

The perovskite PV cell is arranged and fixed by means of an adhesive on the existing PV cell, the adhesive being transparent at least to that sub-spectrum of the light L which comprises the spectral range for which the first PV cell or its light-sensitive component has its maximum efficiency.

In summary, the invention relates to improving the efficiency of an existing, installed PV system. In this case, a film-like, laminated perovskite PV cell is added to an existing PV cell of the existing PV system, if appropriate together with the associated power electronics, and is arranged on the existing PV cell in such a way that light L from a light source which is transmitted by the existing PV System to be converted into electrical energy, first falls on the perovskite PV cell and then on the existing PV cell. A laminated perovskite PV cell is used in such a way that an existing PV system It is increasingly upgraded that its efficiency can be improved without replacing components.

The advantage of the proposed solution lies in the cost-effective way of improving existing PV systems without having to completely replace the existing modules. This upgrade can bring the efficiency of an older system from 15-20% to> 25%. This improvement is all the more pronounced the lower the performance of the existing modules. By precisely fitting the band gap of a perovskite PV cell, all variants of existing PV cells can be combined and their efficiency increased. An existing infrastructure for the installation of an existing system is retained, so that significant savings can be achieved. The existing, old PV cells serve as a holder for the cells to be supplemented. The solution presented here is therefore much more economical than a complete replacement of the old PV modules with new tandem modules. This "upgrade" is independent of the type and manufacturer of the existing PV system; you only have to choose the right size of the perovskite PV cell.

Further advantages and embodiments result from the drawings and the corresponding description.

In the following, the invention and exemplary embodiments are explained in more detail with reference to drawings. There who identified the same components in different figures by the same reference numerals. It is therefore possible that in the description of a second figure for a certain reference number, which has already been explained in connection with another, first figure, there are no further explanations. In such a case, it can be assumed in the embodiment of the second figure that the component identified there by this reference number has the same properties and functionalities even without further explanation in connection with the second figure. points, as explained in connection with the first figure. Furthermore, for the sake of clarity, not all reference numerals are shown in some of the figures, but only those to which reference is made in the description of the respective figure.

Show it:

1 shows a conventional, existing PV system,

2 shows a supplemented PV system,

3 shows a cross section through a laminated perovskite PV cell,

4 shows a plan view of a laminated perovskite PV cell.

Regarding the clarification of terms, it should be noted in advance that terms such as "above", "below", "above", "on", "below" etc. relate to a coordinate system in which the source of the Cell into electrical voltage to convert light, ie, for example, the sun, is "above" the PV cell. In other words, in the case of the tandem PV module mentioned, the perovskite PV cell lies between the light source and the silicon PV cell, i.e. the light source is arranged "above", the silicon cell is "below" and the perovskite cell between the light source and the silicon PV cell. In other words, the pervoskite PV cell is arranged "on" the surface of the silicon PV cell facing the light source.

1 shows, by way of example and in a simplified manner, a PV device 1 with a PV module 100. The PV module 100 comprises a first PV cell 111 of a first cell type, ie with one or more first light-sensitive components 112 made of a first material, which provide an electrical voltage U10 when illuminated with light L. In the following, for the sake of simplicity, the expression that the respective PV cell generates a voltage (or similar) is generally used, which means, however, that this voltage is generated by the respective light-sensitive component of the respective cell.

The first light-sensitive component 112 or the first cell type can, for example, be silicon-based and in a carrier 113 made of glass or the like. be embedded. Fastening devices 115 are also provided, with which the first PV cell 111 can be fastened at a desired location (not shown), for example on a roof of a building or the like.

The PV device 1 also has a first power electronics unit 211, the first power electronics unit 211 being assigned to the first PV cell 111. The one generated by the first PV cell 111 when illuminated

Cell voltage U10 is fed to the power electronics unit 211 via a corresponding electrical connection 11 of the PV device 1. The power electronics unit 211 processes the electrical energy supplied to it as required and in turn provides a voltage Ull, for example an alternating voltage Ull, at its output.

This concept is known per se and is used in already installed, conventional PV systems. As explained in the introduction, efforts are to be made to improve the efficiency of such conventional and already installed PV devices 1, in particular without replacing the installed device. The more efficient PV device 1 'to be created in this way is to be based on a tandem PV module 100' according to FIG. 2, the tandem PV module 100 'being based on the existing PV module 100 according to FIG. 1 shall be. For this purpose, an upgrade is proposed with which the improved PV device 1 'with a tandem PV module 100' according to FIG. 2 is formed from the already installed PV device 1 according to FIG. 1.

2 shows an example and simplifies a PV device 1 'with such a tandem PV module 100'. The tandem PV module 100 'comprises the lower, first PV cell 111 of the first cell type, ie with one or more first light-sensitive components 112 made of the first material, which provide the electrical voltage U10 when illuminated. The lower, first PV cell 111 in FIG. 2 corresponds to the first PV cell 111 shown in FIG. 1 and represents an already installed PV cell. The more efficient tandem PV module 100 'is formed based on this first PV cell 111 or on the existing PV module 100 by adding a second PV cell 121 of a second cell type. The second PV cell 121 of the second cell type accordingly comprises one or more second light-sensitive components 122 made of a second material, which are embedded in a sufficiently transparent material 123 and which provide an electrical voltage U20 when illuminated. The second PV cell 121, which is preferably arranged on or above the first PV cell, is part of the upgrade of the PV device 1 to the improved PV device 1 '. Due to the fact that the second PV cell 121 is arranged above the first PV cell 111, a corresponding assembly is comparatively simple and can ideally be carried out without the existing or installed first PV cell 111 having to be dismantled or removed .

During operation, the tandem PV module 100 'is arranged such that the upper, second PV cell 121 faces the light source L, for example the sun. The light L emitted by the light source L and falling on the tandem PV module 100 'thus first strikes the second PV cell 121, which in a known manner leads to the second PV cell 121 or its light-sensitive Component 122 generates the second electrical cell voltage U20 from the second material. After

Passing through the second PV cell 121, the corresponding residual light falls on the first PV cell 111, which likewise leads, in a known manner, to the first PV cell 111 or its light-sensitive component 112 made of the first material having a first electrical cell voltage U10 generated. The two cell types are advantageously selected such that the maximum efficiency of the different cells 111,

121, which is also referred to as "Power Conversion Efficiency" (PCE), lie in different spectral ranges. In particular, a cell type is selected for the first PV cell 111, the PCE maximum of which lies in a spectral range for which the built-in The state of the upper, second PV cell 121 is essentially transparent. "Essentially transparent" is intended to mean that the second PV cell 121 absorbs this special spectral range significantly less than other spectral ranges. It must of course be assumed that the second PV cell 121 has a certain degree of absorption in every spectral range relevant for this application, but it can also be assumed that the degree of absorption in certain areas of the light spectrum is comparatively low and the cell 121 is therefore “essentially transparent” for this spectral range.

In the example shown, the upper, second PV cell 121 is a perovskite-based PV cell, i.e. the light-sensitive component 122 of the second PV cell 121 has a perwoskitic material. In contrast, the lower, first PV cell 111 is a conventional, for example silicon-based, PV cell. As indicated in the introduction, perovskite materials have a larger band gap than silicon-based materials, which is why the perovskite-based PV cell 121 has a higher absorption component in the blue or short-wave spectral range and transmits longer-wave light. The silicon-based PV cell 111 absorbs more in the longer-wave spectral range, so that the light transmitted by the perovskite cell 121 or at least part of it can be absorbed by the silicon cell 111 and converted into electrical voltage.

The PV device 1 ′ improved by the upgrade comprises the already existing first power electronics unit 211 and a second power electronics unit 221. The second Power electronics unit 221 can accordingly also be part of the upgrade. The cell voltage U20 generated by the second PV cell under illumination is supplied to the second power electronics unit 221 via a corresponding electrical connection 21 of the improved PV device 1 '. The second power electronics unit 221 processes the electrical energy supplied to it as required and in turn provides a voltage U21, for example an AC voltage U21, at its output.

The two power electronics units 211, 221 advantageously work separately and independently of one another. As already described, the first power electronics unit 211 is still assigned to the first PV cell 111, while the second power electronics unit 221 is assigned to the second PV cell 121. The first PV cell 111 and the first power electronics unit 211 form a first PV subsystem 110 of the PV device 1 ′. Likewise, the second PV cell 121 and the second power electronics unit 221 assigned to it form a second PV subsystem 120 of the PV device 1 '. The cell voltages U10, U20 generated by the PV cells 111 under lighting are supplied to the respective power electronics unit 211, 221 via corresponding electrical connections 11, 21 of the PV device 1 'and there, as mentioned, to output voltages Ull, U21 changed.

In principle, it is conceivable that the upgrade only includes the additional PV cell 121, but not the second power electronics unit 221. In this case, the electrical energy or voltage U2 provided by the second PV cell 121 when illuminated would be supplied to the already existing first power electronics unit 211 and processed there.

The PV device 1 'also has a control unit 300 which is designed to operate the power electronics unit 211, 221 of each PV subsystem 110, 120 to regulate the respective power electronics unit 211, 221, for example, in such a way that a product from a current yield 110 or 120 which can be taken from the respective power electronics unit 211, 221 and the respective cell voltage U10 or U20 that is assigned to the respective power electronics unit 211, 221 PV cell 111, 121 is maximum. This leads to the energy yield of the respective PV subsystem

110, 120 is maximum, the essential point being that the optimal working point is approached individually and independently of one another for the PV subsystems 110, 120 due to the availability of separate power electronics units 211, 221. Such a PV device 1 'with a corresponding control unit is described, for example, in WO 2018162496 A1, already quoted.

The lower, first PV cell 111 in FIG. 2 corresponds to the first PV cell 111 shown in FIG. 1 and represents an already installed PV cell. The second PV cell 121 represents a PV cell subsequently added to the PV device 1 as part of the upgrade, so that the tandem PV module 100 'is created by adding the second cell 121 to the first cell 111. The same applies to the additional power electronics unit 221. In particular, when adding or upgrading the PV device 1 shown in FIG. 1 to the improved PV device 1 'shown in FIG. 2, all components 11,

111, 112, 113, 115, 211 of the original PV device 1 can continue to be used.

3 shows a detailed view of the second PV cell 121 of the tandem PV module 100 '. The hatching of the light-seated component 122, which in FIG. 2 was used in particular to illustrate the different cell types of the PV cells 111, 121, is not used in FIG. 3 for the sake of clarity. As already described, the module 100 'consists of the first, already installed PV cell 111. As part of the upgrade, the second PV cell 121 shown in FIG. 3 is positioned on this first cell 111. The The second PV cell 121 is designed in particular as a laminated unit which is to be applied and fixed on the surface of the first PV cell 111, for example with the aid of a correspondingly at least partially transparent adhesive 129, for example a so-called liquid, optically transparent adhesive .

As indicated in FIG. 3, the second PV cell 121 comprises a perovskite layer 122 which has an n-doped region 122n and a p-doped region 122p. On the two surfaces of the perovskite layer 122, transparent laminations 123o, 123u are applied, which adjoin one another at the dashed line and which include the perovskite layer 122, which has the advantage that the

Perovskite layer 122 is protected against moisture and dirt. The inclusion is also achieved in that the lamination layers 123o, 123u protrude beyond the light-sensitive component 122 in the horizontal directions x, y. This is also clear in the top view in FIG. 4.

FIG. 3 also indicates the electrical connection of the second PV cell 121 and shows the electrical connection 21 which leads to the second power electronics unit 221 (not shown in FIG. 3). In the example shown here, the electrical connection 21 comprises two electrical lines 21n, 21p, the line 21n being electrically contacted with the n-doped region 122n and the line 21p with the p-doped region 122p. When the second PV cell 121 is illuminated, an electrical voltage is produced in a known manner, which can be tapped via contacts 122k and supplied to the second power electronics unit 221 via the lines 21n, 21p.

FIG. 4 shows a top view of the second PV cell 121 shown in FIG. 3. As an example, the second PV module 121 has a square shape. Due to the viewing direction in the negative, vertical z-direction, only the upper lamination layer 123o and the n-doped region 122n of the light-sensitive component 122 are visible. The spatial boundaries of the area 122n are shown in dashed lines, since the light-sensitive component 122 lies under the upper lamination 123o. In principle, however, the lamination 123o, like the lamination 123u not shown, consequently has larger dimensions in the horizontal directions x, y than the light-sensitive component 122, in order to ensure that the light-sensitive component 122 is protected against dirt and moisture protects.

Deviating from the design of the light-sensitive components 122 of the perovskite PV cell indicated in FIG. 3 and FIG. 4

121 as a single comparatively large-area component 122, it can also consist of a large number of smaller, light-sensitive components arranged, for example, in the manner of a checkerboard pattern, which in the end, however, are likewise enclosed with an upper and a lower lamination. At this point it is less important how the perovskite light-sensitive component 122 is designed, but rather that it is enclosed or encapsulated with the laminations 123o, 123u.

The perovskite-based PV cell 121 is based on thin-film technology. Accordingly, it must be taken into account that the representations are not to scale. Due to the corresponding small extent of the pervoskite layer

122 in the z-direction, it is possible to laminate the layer 122 or the light-sensitive material 122 in the transparent films 123o, 123u. The resulting perovskite PV cell 121, comprising the light-sensitive component 122 and the lamination 1230, 123u, in turn has the properties of a film, and is therefore, in particular, comparatively flexible and easy to handle.

In order to produce such a perovskite PV cell 121 with the purpose of expanding the existing PV device 1, the second PV cell 122 and the second light-sensitive component 122 are first in one of the first PV cell 111 and in particular the first light-sensitive component 112 Size made. E.g. This can be done in such a way that the extensions of the second light-sensitive component 122 in the Cartesian, horizontal x and y directions correspond to the extensions of the first component 112 in these directions. The second light-sensitive component 122 provided in this way is then laminated with the lamination layers 123o, 123u, the extent of which in the x and y directions being selected, for example, in such a way that the extent of the first PV cell 111, for example correspond to the extensions of the carrier 113 in the x and y directions.

Ideally, the perovskite PV cell 121 thus produced is attached to the existing first PV cell 111 without the first PV cell 111 having to be uninstalled. Should a temporary deinstallation of the existing PV cell 111 be necessary in order to accomplish the attachment of the perovskite PV cell 121 to the existing PV cell 111, it can be assumed that this is after the cells 111, 121 have been attached to one another generated tandem PV module 100 'is reinstalled at exactly the location where the PV cell 111 was previously installed. The attachment can, for example, with the aid of an at least partially transparent adhesive 129. This is selected such that it is transparent at least for the part of the light spectrum in which the first PV cell 111 has its maximum efficiency. After fastening the second PV cell 121 to the first PV cell 111, the second PV cell 121 is electrically contacted. In the ideal embodiment of the extension or upgrade, a separate power electronics unit 221 is provided, to which the second PV cell 121 is electrically connected via the lines 21n, 21p. The second power electronics unit 221 is finally connected to the control unit 300. An upgrade is also provided for the control unit 300, which ideally only consists of customized software. If the existing control unit 300 cannot be upgraded accordingly, a separate control unit 300 'can be provided for the second PV cell 121. This option is shown in FIG. 2 with the aid of dashed lines. points. In such a case, it would be a good idea to connect the Re 300, 300 'together. It is also advantageous if one of the two controls 300, 300 'works as a "master" and the other control unit 300', 300 can control or regulate.

With the quick and easy upgrade of an existing PV system 1 to a highly efficient and technically and economically competitive PV system 1 'that can be achieved, many of the components of the existing PV system 1 can be retained. This also addresses an important aspect of sustainability.

Reference calibrate _Z

I PV facility

1 'more efficient PV facility

II electrical connection

21 electrical connection

100 existing PV modules

100 'tandem PV module

110 first PV subsystem

III first PV cell

112 first light-sensitive component

113 carriers

115 fastening device

120 second PV subsystem

121 second PV cell

122 perovskite layer

122 second light sensitive component, perovskite layer 122k electrical contacts

122n n-doped region

122p p-doped region

123 transparent material, carrier

123o lamination

123u lamination

129 transparent adhesive

211 first power electronics unit

21n electrical wire

21p electrical wire

221 second power electronics unit

300 control unit

300 'control unit

L light

Claims

1. PV system supplementary device for supplementing an existing PV system (100, 200, 300) which comprises at least one existing PV cell (111) of a first cell type, having a perovskite PV cell (121) with a flat, perovskite-based light-sensitive component (122), where

- The light-sensitive component (122) has a first surface and a second surface opposite the first surface, with a lamination (123o, 123u) being applied to the first and second surfaces, so that the light-sensitive component (122 ) is completely enclosed by the laminations (123o, 123u),

- The perovskite PV cell (121) is dimensioned such that it can be fastened on a surface of the existing PV cell (111).

2. PV system supplementary device according to claim 1, characterized in that the perovskite PV cell (121) has a holding tion (129) with which the perovskite PV cell (121) on the existing PV cell ( 111) can be fastened in such a way that it is fixed in space to the existing PV cell (111) and that light L is first of all directed onto the

Perovskite PV cell (121) and then falls on the existing PV cell (111).

3. PV system supplementary device according to one of claims 1 to 2, characterized in that the supplementary device comprises a power electronics unit (221) which

- The perovskite PV cell (121) is assigned,

an electrical voltage U20 provided by the perovskite PV cell (121) when illuminated with the light L converts into an electrical voltage U21 to be provided at an output of the power electronics unit (221), - Can be connected to an existing power electronics (211) and / or an existing control unit (300) of the existing PV system (100, 200, 300).

4. PV system supplementary device according to one of claims 1 to 2, characterized in that the supplementary device comprises a separate control unit (300 '),

- With which the power electronics unit (221) can be regulated and

- Which can be connected to the existing control unit (300) of the existing PV system (100, 200, 300), so that data exchange between the separate control unit

(300 ') and the existing control unit (300) is possible.

5. Use of a perovskite PV cell (121) to improve the efficiency of an existing PV system by means of a PV system supplementary device according to one of claims 1 to 4, wherein the perovskite PV cell (121) of an existing PV Cell (111) of the existing PV system (100, 200, 300) is added.

6. Extended PV system (1 ') for providing electrical voltage when illuminating the extended PV system (1') with light L from a light source, comprising

an existing PV system (100, 200, 300) which comprises at least one existing PV cell (111) of a first cell type,

- A subsequently installed PV system supplementary device according to claim 1 with a laminated perovskite PV cell (121).

7. Extended PV system (1 ') according to claim 6, characterized in that the perovskite PV cell (121) has a holder (129) by means of which the perovskite PV cell (121) in such a way on the existing PV cell (111) is fixed that the light L first on the light-sensitive component (122) of the perovskite PV cell (121) and then on the light sensitive component (112) of the existing PV cell (111) falls.

8. Extended PV system (1 ') according to claim 7, characterized in that the holder (129) for fastening the

Perovskite PV cell (121) on the existing PV cell (111) is an at least partially transparent adhesive, wherein

- The perovskite PV cell (121) is glued by means of the adhesive (129) to that surface of the existing PV cell (111) through which the light L from the light source onto a light-sensitive component (112) of the existing PV cell (111) falls

- The adhesive (129) is transparent at least for that sub-spectrum of the light L, which includes that spectral range for which the first PV cell (111) has its maximum efficiency.

9. Extended PV system (1 ') according to one of claims 6 to 8, characterized in that the PV system supplementary device comprises a separate power electronics unit (221) which is assigned to the perovskite PV cell (121) and converts the electrical voltage U20 provided by the perovskite PV cell (121) when illuminated with the light L, if necessary, into an electrical voltage U21 to be provided at an output of the separate power electronics unit (221).

10. Extended PV system (1 ') according to claim 9, wherein the existing PV system (100, 200, 300) has an existing power electronics unit (211) which is assigned to the existing PV cell (111) and an electrical voltage U10 provided by the existing PV cell (111) when illuminated with the light L converts, if necessary, into an electrical voltage Ull to be provided at an output of the existing power electronics unit (211), the existing power electronics unit (211) of an existing control unit (300) of the existing PV system (100, 200, 300) can be regulated, characterized in that the separate power electronics unit (221) of the perovskite PV cell (121) with the existing power electronics unit (211) and / or with the existing control unit (300) of the existing PV system (100, 200, 300) can also be connected by the existing control unit (300) can be regulated.

11. A method for improving the efficiency of an existing PV system (100, 200, 300), characterized in that an existing PV cell (111) of the existing PV system (100, 200, 300) is a perovskite PV cell (121) is added and arranged on the existing PV cell (111) in such a way that light L from a light source, which is to be converted into electrical energy by the existing PV system (100, 200, 300), first turns on the perovskite PV cell (121) and then falls on the existing PV cell (111).

12. The method according to claim 11, characterized in that a perovskite-based light-sensitive component (122) is laminated to produce the perovskite PV cell (121) to be added, the light-sensitive component (122) being made of laminating layers (123o, 123u). is included in such a way that the light-sensitive component (122) is protected from dirt and moisture.

13. The method according to claim 12, characterized in that the dimensioning of the perovskite PV cell (121) to be added is adapted to the dimensioning of the existing PV cell (111), in particular the horizontal extensions of the lamination layers (123o, 123u) in the x and y directions and the corresponding horizontal extensions of a carrier (113) of the existing PV cell (111) in which the light-sensitive component (112) of the existing PV cell (111) is embedded largely correspond to one another.

14. The method according to any one of claims 11 to 13, characterized in that the perovskite PV cell (121) is arranged and fastened on the existing PV cell (111) by means of an adhesive (129), the adhesive (129 ) at least for that- that partial spectrum of the light L is transparent, which comprises the spectral range for which the first PV cell (111) has its maximum efficiency.