System and method for reducing the salt content of a liquid
Patent Information
- Application Number
- PCT/EP2026/054119
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-17
- Filing Date
- 2026-02-16
- Publication Date
- 2026-09-24
Smart Images
Figure EP2026054119_24092026_PF_FP_ABST
Abstract
Description
[0001] HEESCHEN.PULTZ
[0002] PATENT ATTORNEYS
[0003] Hamburg, February 16, 2026
[0004] Our reference: P-2025-003 DE HE / db
[0005] Applicant / Owner: Schall Holding UG
[0006] Official file number: PCT subsequent registration
[0007] System and method for reducing the salt content of a base liquid
[0008] The invention relates to a system and a method for reducing the salt content of a base liquid, in particular salt water, preferably seawater.
[0009] Systems for reducing the salinity of saltwater or seawater are generally known. Seawater desalination is particularly well-known as the production of drinking water or process water from seawater, especially saltwater. This is achieved by reducing the salinity.
[0010] Seawater desalination can be achieved through various physical and / or chemical processes. These processes typically involve removing dissolved ions from the water. Seawater desalination usually produces brine, an aqueous solution with a high salt concentration. This brine is generally returned to the sea.
[0011] One approach to seawater desalination is multi-stage flash evaporation. Multi-stage flash evaporation is a thermal process. In this process, the supplied seawater is heated to a high temperature. The heated saltwater then evaporates in subsequent flash evaporation stages, particularly under vacuum. The water vapor condenses within these stages on pipes filled with cooling fluid and is drawn off as salt-free water.
[0012] Another method for seawater desalination is reverse osmosis. In reverse osmosis, seawater is forced under high pressure through a semipermeable membrane, for example made of polyamide, PTFE or sulfonated copolymers with a pore diameter of 0.5 to 5 nm, to overcome the osmotic pressure.
[0013] The membrane acts like a filter, allowing only certain ions and molecules to pass through. This process splits the seawater. The membrane filter retains salts, but also bacteria, viruses, and excess calcium. Osmotic pressure increases with rising salt concentration, eventually halting the process. To counteract this, the concentrated salt is removed and fresh seawater is added.
[0014] Another method for seawater desalination is membrane distillation. This process uses a microporous membrane that only allows water vapor to pass through, while retaining liquid water. Warm salt water is present on one side of the membrane, and a colder surface on the other. The countercurrent operation of the system ensures a temperature difference along the entire length of the membrane. The resulting difference in water vapor partial pressure causes water molecules to move from the warm to the cold side of the membrane.
[0015] The demand for seawater desalination plants is constantly increasing due to the growing need for drinking water and clean process water, for example, for hydrogen production. One disadvantage of seawater desalination plants is their high energy consumption, particularly electricity. Since electricity is generally generated primarily from fossil fuels, seawater desalination is often a high-emission process.
[0016] Furthermore, in many seawater desalination processes, only about 40% of the water is converted into drinking water or low-salinity process water, while the remaining 60% is discharged back into the sea as brine. This brine is more saline than seawater and leads to an increase in the sea's salinity. This causes environmental damage in the vicinity of seawater desalination plants. In addition, particularly in seawater desalination plants that operate on the basis of reverse osmosis, chemical cleaning agents are used, which are also discharged into the sea and can thus lead to environmental damage.
[0017] WO 2020 000 004 A1 discloses an apparatus and a method for solar seawater desalination. The apparatus has an evaporation chamber comprising a housing, an evaporation vessel with inlet and outlet, and a heating window. A disadvantage of this apparatus is its low desalination capacity.
[0018] German patent DE 10 2012 014 560 A1 discloses water-self-sufficient greenhouses powered by solar energy. This involves solar seawater desalination using greenhouses, with the desalination taking place in a series of two or more greenhouses arranged one behind the other. One disadvantage of this method is the high energy consumption for seawater desalination.
[0019] German patent DE 102012000016 A1 discloses a method for generating fresh water and electricity from seawater or process water using solar energy. The electricity is to be generated using flat-plate collectors. The energy-intensive operation of seawater desalination plants typically requires so many photovoltaic systems that the exclusive use of photovoltaic systems is often not economically viable.
[0020] An object of the present invention is to reduce or eliminate at least one disadvantage of a known solution or to propose an alternative solution. In particular, it is an object of the present invention to provide a system and a method for reducing the salt content of a base liquid, thereby reducing or eliminating one or more of the aforementioned disadvantages. It is also an object of the invention to provide a solution that enables self-sufficient and / or economical desalination of a base liquid. This object is achieved by a system and a method according to the features of the independent claims. Further advantageous embodiments of these aspects are specified in the respective dependent claims.The features disclosed in the claims, the description and the drawings can be combined individually in any technologically meaningful way, with further embodiments of the invention being shown.
[0021] According to a first aspect, the aforementioned problem is solved by a system for reducing the salt content of a base liquid, in particular salt water, preferably seawater, comprising an electrically operated liquid desalination device, which is arranged and configured to separate the base liquid into a low-salt liquid and a high-salt liquid; a brine device fluidically coupled to the liquid desalination device, with at least one receiving basin, which is arranged and configured to receive the high-salt liquid and to form a reflective surface; and a photovoltaic device with at least one photovoltaic module, which is arranged and configured to supply electrical energy to the liquid desalination device, wherein the photovoltaic device and the brine device are arranged and configured such thatthat, during normal operation, light reflected from the reflective surface can be converted by the photovoltaic device to increase the power output of the photovoltaic device.
[0022] The invention is based on the understanding that the simple combination of a seawater desalination plant and a photovoltaic system is insufficient to ensure economical and / or self-sufficient operation of the seawater desalination plant. The invention is based on the understanding that by combining a liquid desalination unit, a brine unit, and a suitably arranged photovoltaic system, the liquid desalination unit can be supplied with a smaller number of photovoltaic modules. A further advantage of this combination is that the environmental impact on seawater can be reduced by eliminating or minimizing the amount of saline water discharged into the sea.
[0023] The system is designed to reduce the salt content of a base liquid. The base liquid can be, in particular, salt water, preferably seawater, whose salt content is, for example, higher than that of drinking water or special process water for various applications. A reduction in salt content is understood to mean, in particular, a reduction in the percentage salt content of the base liquid of more than 0.1 percentage points, 0.2 percentage points, 0.5 percentage points, and especially more than 1 percentage point.
[0024] The system includes an electrically powered liquid desalination unit. The liquid desalination unit is designed and configured to separate the base liquid into a low-salt liquid and a high-salt liquid. The liquid desalination unit can also be referred to as a seawater desalination unit.
[0025] The input of the liquid desalination device includes, among other things, the base liquid. The output of the liquid desalination device consists of the low-salt liquid and the high-salt liquid. The low-salt liquid is characterized by its lower salt content compared to the high-salt liquid. The high-salt liquid can also be referred to as brine. The basic operating principles of the various forms of liquid desalination are well known to those skilled in the art.
[0026] The system further comprises the brine device fluidically coupled to the liquid desalination unit. The brine device includes at least one receiving basin. The receiving basin is arranged and designed such that the salt-rich liquid can be collected and a reflective surface is formed.
[0027] The fluidic coupling of the liquid desalination unit and the brine unit can be achieved, for example, with a fluid-carrying connection such as pipes. The liquid desalination unit can, for instance, have an outlet for the saline liquid, with this outlet being fluidically coupled to the receiving basin. In addition to the receiving basin, the brine unit can include other components. For example, the brine unit can include various basins, pumps, sluices, and other units.
[0028] The system further comprises a photovoltaic device with at least one photovoltaic module. The photovoltaic device is arranged and configured to supply electrical energy to the liquid desalination device. In addition to the photovoltaic module, the photovoltaic device may, in particular, include a frame, various electrotechnical components, and drives. It is especially preferred that the photovoltaic device comprises two or more photovoltaic modules, and in particular a plurality of photovoltaic modules. It is preferred that the photovoltaic device is arranged and configured to generate a larger quantity of electrical energy that can be supplied to a public power grid and / or other consumers of the system.
[0029] The photovoltaic device and the saltworks are arranged and designed such that, during normal operation, light reflected from the reflective surface can be converted into electrical energy by the photovoltaic device, thereby increasing its power output. It is also a feature of the invention that the reflective surface formed by a saltworks, particularly the water surface beneath which the white salt is located, and / or a salt surface itself, can provide high solar power. The light reflected from the reflective surface thus increases the energy yield of the photovoltaic device. In particular, the high partial reflection at the reflective surface of the saltworks significantly increases the power output of the photovoltaic device, requiring only a small number of photovoltaic modules.
[0030] The photovoltaic module is therefore arranged in such a way that it absorbs both direct sunlight and reflected light. To utilize the advantages of direct sunlight and reflected light, various arrangement options for the photovoltaic module exist, which will be explained in more detail below.
[0031] In a preferred embodiment of the system, the at least one photovoltaic module is arranged, or can be arranged, vertically. Particularly when the sun is low in the sky, a vertically oriented photovoltaic module can provide high power output.
[0032] A preferred further development of the system is characterized by the fact that the at least one photovoltaic module is designed as a bifacial photovoltaic module with a primary and a secondary side and can be arranged such that sunlight strikes the primary side and the light reflected from the receiving basin strikes the secondary side. Bifacial generally describes the ability of a photovoltaic module to utilize sunlight from both its front and back sides for power generation. Bifacial photovoltaic modules are particularly distinguished by the fact that they have power-generating elements on both broad sides. Thus, direct sunlight can be converted into energy via the primary side, and reflected light via the secondary side.
[0033] Another preferred embodiment of the system is characterized by the fact that the at least one photovoltaic module is arranged to be movable, in particular tiltable and / or rotatable, in order to increase the provision of electrical energy.
[0034] The photovoltaic module can be tilted and / or rotated, for example, depending on the daily solar irradiance. Furthermore, the photovoltaic module can be tilted and / or rotated depending on the season. It is particularly preferred that the tiltable photovoltaic module can be tilted about a horizontal axis. It is also preferable that the rotatably arranged photovoltaic module can be moved about a vertical axis. The movable arrangement of the photovoltaic module, especially by tilting and / or rotating it, can increase the yield of electrical energy, as the photovoltaic module can be aligned towards the sun and / or the reflected light.It is preferred that the system includes a light sensor arranged and configured to detect the incident sunlight and / or the reflected light in such a way that the photovoltaic module can be aligned based on information representing this. Preferably, the system includes a control device for this purpose.
[0035] A further preferred embodiment of the system is characterized by the fact that the at least one photovoltaic module is arranged at least partially vertically above the receiving basin. It is particularly preferred that the at least one photovoltaic module is arranged completely vertically above the receiving basin. Alternatively or additionally, the at least one photovoltaic module and / or further photovoltaic modules can be arranged on an edge of the receiving basin. In particular, such photovoltaic modules that are arranged partially or completely above the receiving basin can capture a large amount of reflected light and thus convert it into electrical energy.
[0036] A preferred embodiment of the system comprises a foundation on which the at least one photovoltaic module is arranged, wherein the saline device includes the foundation.
[0037] The foundation is specifically designed and constructed so that one surface of the foundation is generally above the water level of the receiving basin. The photovoltaic module and its associated frame can be positioned on the foundation in such a way as to minimize their exposure to the corrosive effects of the saline liquid in the receiving basin.
[0038] The foundation can, for example, be located at the bottom of the receiving pool. Alternatively or additionally, the foundation can form part of the receiving pool and / or the pool floor.
[0039] In another preferred embodiment of the system, the foundation divides the receiving basin into at least two individual receiving basins and preferably seals them in a fluid-tight manner. Multiple individual receiving basins of the brine system offer the advantage that the salt concentration can be increased from one receiving basin to the next. Consequently, the liquid content can be continuously reduced, and pure salt can be obtained from the last receiving basin provided in this way, which can then be utilized. Separating the individual receiving basins from the foundation for the at least one photovoltaic module has the advantage that no further partitions are required for the individual receiving basins.
[0040] Another preferred embodiment of the system is characterized by a strip-shaped foundation that preferably extends from a first side of the receiving basin to an opposite second side, and by the at least one photovoltaic module extending along the strip-shaped foundation. The fact that the at least one photovoltaic module extends along the strip-shaped foundation can, in particular, mean that it extends partially or completely along the strip-shaped foundation.
[0041] Such an arrangement increases the energy yield of the at least one photovoltaic module, especially if it is designed as a bifacial photovoltaic module.
[0042] A preferred further development of the system is further characterized by the fact that the receiving basin is arranged and designed in such a way that a liquid height between 0 cm and 500 cm can be adjusted.
[0043] In another preferred embodiment of the system, the receiving basin is provided to have a polished and / or a white surface to enable high partial reflection, thus maximizing the reflected light. Furthermore, it may be preferred that the receiving basin has a foil-coated surface.
[0044] Especially at the beginning of use, or if the settled salt has just been skimmed off, it is advantageous if the surface of the receiving basin reflects as much light as possible to enable the previously described effect of better energy yield from the photovoltaic modules.
[0045] In a further preferred embodiment of the system, the saline device is arranged and configured to extract the salt from the salt-rich liquid and preferably to evaporate the liquid components of the salt-rich liquid.
[0046] A particular advantage of this design is that it avoids the environmentally harmful return of the brine to the seawater. Furthermore, the extracted salt can be used for other purposes.
[0047] In another preferred embodiment, the system includes a battery storage system electrically coupled to the photovoltaic device for storing electrical energy provided by the photovoltaic device.
[0048] Such a battery storage system can, for example, temporarily store excess electrical energy and use it in the event of high system energy demand or during periods of lower electricity generation by the photovoltaic system. Furthermore, the stored electrical energy can be fed into a public grid during periods of high electricity prices.
[0049] In another preferred embodiment of the system, the liquid desalination device is arranged and configured to separate the base liquid into the low-salt liquid and the high-salt liquid by means of reverse osmosis.
[0050] According to a further aspect, the aforementioned problem is solved by a method for reducing the salt content of a base liquid, in particular salt water, preferably seawater, comprising the steps of: separating the base liquid into a low-salt liquid and a high-salt liquid; collecting the high-salt liquid in a receiving basin of a salinity apparatus; and providing electrical energy for separating the base liquid using a photovoltaic device, wherein the photovoltaic device and the salinity apparatus are arranged and configured such that, during intended operation, light reflected from the receiving basin can be converted into electrical energy by the photovoltaic device to increase the power output of the photovoltaic device. It is preferred that the method includes the step of: vertically aligning at least one photovoltaic module of the photovoltaic device.The at least one photovoltaic module can be a bifacial photovoltaic module. Furthermore, it is preferred that the method includes the step of moving, in particular tilting and / or rotating, the photovoltaic module to increase the provision of electrical energy. It is also preferred that the method includes the step of conveying the saline liquid from one single receiving basin to another single receiving basin. Furthermore, it is preferred that the method includes the step of extracting salt from the saline liquid. In particular, the method includes the step of evaporating the liquid components of the saline liquid to extract the salt.
[0051] Furthermore, the procedure may include the step of storing electrical energy provided by the photovoltaic device, in particular with a battery storage system that is electrically coupled to the photovoltaic device.
[0052] Furthermore, the process may preferably include the step of separating the low-salt liquid and the high-salt liquid by means of reverse osmosis.
[0053] For further advantages, design variants and design details of the individual aspects and their possible further training, reference is also made to the description of the further aspects, the corresponding characteristics and further training.
[0054] Preferred embodiments are explained by way of example with reference to the accompanying figures. These show:
[0055] Figure 1: a schematic, two-dimensional top view of an exemplary embodiment of a system for reducing the salt content of a base liquid; Figure 2: a schematic, two-dimensional top view of an exemplary embodiment of a brine device;
[0056] Figure 3: a schematic, two-dimensional side view of an exemplary embodiment of a saltworks device;
[0057] Figure 4: a schematic, two-dimensional side view of an exemplary embodiment of a saltworks device;
[0058] Figure 5: a schematic, two-dimensional side view of an exemplary embodiment of a saltworks device;
[0059] Figure 6: a schematic view of an exemplary procedure.
[0060] In the figures, identical or essentially functionally equivalent or similar elements are designated with the same reference symbols.
[0061] The exemplary embodiments described below are preferred embodiments of the invention. In these exemplary embodiments, the described components each represent individual features of the invention that can be considered independently of one another. These features further develop the invention independently and can also be regarded as part of the invention individually or in a combination other than that shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.
[0062] Figure 1 shows a system 100 for reducing the salinity of a base liquid, which in this embodiment is seawater 102. The system 100 is therefore located adjacent to a body of water containing seawater 102. The system 100 comprises a liquid desalination unit 110, which is connected to the seawater 102 by means of an inlet unit 112. The liquid desalination unit 110 is designed to separate the seawater 102 into a low-salt liquid 104 and a high-salt liquid 106. This separation can be carried out, for example, by reverse osmosis. The liquid desalination unit 110 also has an outlet unit 114 for the low-salt liquid 104 and another outlet unit 116 for the high-salt liquid 106.The low-salt liquid 104 can be extracted for further use at the discharge unit 114 or fed into a subsequent process, for example hydrogen production.
[0063] The discharge unit 116 for the saline liquid 106, unlike the industry standard, is not connected to the seawater 102, but to the saline device 120. The saline device 120 has the receiving basin 122, which is arranged and designed to receive the saline liquid 106 and to form a reflective surface 123.
[0064] Receiving basin 122 is divided into five individual receiving basins 124, 126, 128, 130, 132. In particular, receiving basin 122 is divided into individual receiving basins 124 to 132 by means of foundations 134, 136, 138, 140.
[0065] A photovoltaic system 150 is arranged on foundations 134 to 140. The photovoltaic system 150 comprises several photovoltaic modules 152, 154, 156, 158, which are arranged and configured to supply electrical energy to the liquid desalination system 110. The photovoltaic modules 152 to 158 are arranged on foundations 134 to 140. The foundations 134 to 140 extend in a strip shape from one side of the receiving basin 122 to the other side of the receiving basin 122. The photovoltaic modules 152 to 158 are electrically connected to the liquid desalination system 110 and a grid connection point 160 by means of a power line 162.
[0066] Figure 2 shows another embodiment of a saltworks device 200 with a receiving basin 202 extending from a first side 202a to a second side 202b. The receiving basin 202 has three individual receiving basins 204, 206, 208, which are separated from each other by the foundations 210, 212. The receiving basin or the individual receiving basins 204, 206, 208 form the reflective surface 203. The photovoltaic device 214 with the photovoltaic modules 216, 218 is arranged on the strip-shaped foundations 210, 212.
[0067] Figure 3 shows another embodiment of a saltworks device 220 with a receiving basin 222, which is divided into individual receiving basins 226, 228, 230. The receiving basin 222 and the individual receiving basins 226, 228, 230 form the reflective surface 224. The reflective surface 224 is particularly strongly partially reflective, since the salt layer 223 is located beneath a layer of water.
[0068] The photovoltaic system 236 with the photovoltaic modules 238, 240 is arranged on the foundations 232, 234. The photovoltaic modules 238, 240 are vertically oriented.
[0069] Figures 4 and 5 show a further embodiment of a saltworks device 242, which has a receiving basin 244 that provides the reflective surface 246. The receiving basin 244 is divided into the individual receiving basins 248, 250, 252 by the foundations 254, 256 extending from one side to the other of the receiving basin 244.
[0070] The photovoltaic device 258 with the photovoltaic modules 260, 262 is arranged on the foundations 254, 256. The photovoltaic modules 260, 262 are arranged to be tiltable, so that they can have not only the vertical orientation shown in Figure 4, but also the tilted arrangement shown in Figure 5. Thus, on the one hand, the direct sunlight coming from above can be used by the photovoltaic modules 260, 262 to convert it into electrical energy, and on the other hand, the light 266, 268 reflected on the reflective surface 246 by the salt layer 264, which is shown schematically in Figure 5, can be used advantageously.
[0071] Figure 6 shows a method for reducing the salinity of seawater 102. In step 200, seawater 102 is separated into a low-salt liquid 104 and a high-salt liquid 106. The low-salt liquid 104 can be, for example, drinking water. The high-salt liquid 106 can be, in particular, highly saline water, such as brine. In step 202, the high-salt liquid 106 is received in a receiving tank 122, 202, 222, 244. For example, the high-salt liquid 106 can be pumped from the liquid desalination device 110 described above into the receiving tank 122, 202, 222, 244.
[0072] In step 204, electrical energy is provided for separating the seawater using a photovoltaic device 150, 214, 236, 258. The photovoltaic device 150, 214, 236, 258 and the salting device 120, 200, 220, 242 are arranged and designed such that, during normal operation, light 266, 268 reflected from the receiving basin 122, 202, 222, 244 can be converted into electrical energy by the photovoltaic device 150, 214, 236, 258 to increase the power output of the photovoltaic device 150, 214, 236, 258.
[0073] The system and corresponding procedure described above offer several advantages. System 100 can operate largely autonomously, as sufficient electrical energy can be provided by the photovoltaic device 150, 214, 236, 258. This is particularly economical because the installed photovoltaic device 150, 214, 236, 258 produces a particularly large amount of electrical energy by utilizing the reflected light from the saltworks device 120, 200, 220, 242.
[0074] Furthermore, a second commodity, namely salt, can be produced simultaneously during this seawater desalination process. Additionally, the saline liquid 106 is not pumped back into the seawater 102 after separation, thus preventing oversalinization of the sea and further increasing the environmental compatibility of system 100. REFERENCE MARK 100 System
[0075] 102 Seawater
[0076] 104 low-salt liquid
[0077] 106 high-salt liquid
[0078] 110 Liquid demineralization device 112 Inlet unit
[0079] 114 Drainage Unit
[0080] 116 Drainage unit
[0081] 120 saltworks
[0082] 122 receiving basins
[0083] 123 Reflective surface
[0084] 124 individual intake tanks
[0085] 126 individual intake tanks
[0086] 128 individual intake tanks
[0087] 130 individual intake tanks
[0088] 132 single-reception pools
[0089] 134 Foundation
[0090] 136 Foundation
[0091] 138 Foundation
[0092] 140 Foundation
[0093] 150 photovoltaic devices
[0094] 152 photovoltaic modules
[0095] 154 photovoltaic module 156 photovoltaic module 158 photovoltaic module 160 grid feed.
[0096] 162 Power line
[0097] 200 Saltworks device 202 Receiving basin 202a first page
[0098] 202b second page
[0099] 203 Reflection surface 204 Individual intake basin 206 Individual intake basin 208 Individual intake basin 210 Foundation
[0100] 212 Foundation
[0101] 214 Photovoltaic device 216 Photovoltaic module 218 Photovoltaic module 220 Saltworks device 222 Receiving basin 223 Salt layer
[0102] 224 Reflective surface 226 Single intake basin 228 Single intake basin 230 Single intake basin 232 Foundation
[0103] 234 Foundation
[0104] 236 Photovoltaic device 238 Photovoltaic module 240 Photovoltaic module 242 Saltwater device 244 Receiving basin 246 Reflective surface 248 Individual receiving basin 250 Individual receiving basin 252 Individual receiving basin 254 Foundation
[0105] 256 Foundation
[0106] 258 Photovoltaic device 260 Photovoltaic module 262 Photovoltaic module 264 Salt layer
[0107] 266 reflected light 268 reflected light
Claims
REQUIREMENTS 1. System (100) for reducing the salinity of a base liquid, in particular seawater (102), comprising an electrically powered liquid desalination device (110) which is arranged and designed to separate the base liquid into a low-salt liquid (104) and a high-salt liquid (106), a saline device (120, 200, 220, 242) fluidically coupled to the liquid desalination device (110) with at least one receiving basin (122, 202, 222, 244) which is arranged and configured to receive the salt-rich liquid (106) and to form a reflective surface (123, 203, 224, 246), a photovoltaic device (150, 214, 236, 258) with at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) which is arranged and configured to provide electrical energy to the liquid desalination device (110), - wherein the photovoltaic device (150, 214, 236, 258) and the saltworks device (120, 200, 220, 242) are arranged and designed such that, in normal operation, light (266, 268) reflected from the reflective surface (123, 203, 224, 246) can be converted by the photovoltaic device (150, 214, 236, 258) to increase the power of the photovoltaic device (150, 214, 236, 258).
2. System (100) according to claim 1, wherein that at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) is arranged or can be arranged vertically.
3. System (100) according to any one of the preceding claims, wherein that at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) is designed as a bifacial photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) with a primary and a secondary side and can be arranged in such a way that sunlight hits the primary side and the light reflected from the receiving basin (122, 202, 222, 244) hits the secondary side.
4. System (100) according to any one of the preceding claims, wherein that at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) is arranged to be movable, in particular tiltable and / or rotatable, in order to increase the provision of electrical energy.
5. System (100) according to any one of the preceding claims, wherein that at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) is arranged at least partially vertically above the receiving basin (122, 202, 222, 244).
6. System (100) according to any one of the preceding claims, comprising - a foundation (134-140, 210, 212, 232, 234, 254, 256) on which the at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) is arranged, - wherein the saltworks apparatus (120, 200, 220, 242) comprises the foundation (134-140, 210, 212, 232, 234, 254, 256).
7. System (100) according to the preceding claim, wherein - the foundation (134-140, 210, 212, 232, 234, 254, 256) divides the receiving basin (122, 202, 222, 244) into at least two individual receiving basins (124-132, 204-208, 226-230, 248-252) and preferably seals in a fluid-tight manner.
8. System (100) according to one of the preceding claims, wherein the foundation (134-140, 210, 212, 232, 234, 254, 256) is strip-shaped and preferably extends from a first side (202a) of the receiving basin (122, 202, 222, 244) to an opposite second side (202b), and the at least one photovoltaic module (152-158, 216, 218, 238, 240, 260, 262) extends along the strip-shaped foundation (134-140, 210, 212, 232, 234, 254, 256).
9. System (100) according to any one of the preceding claims, wherein the receiving basin (122, 202, 222, 244) is arranged and designed such that a liquid height between 0 cm and 500 cm can be adjusted.
10. System (100) according to any one of the preceding claims, wherein the receiving basin (122, 202, 222, 244) has a polished and / or a white surface to allow high partial reflection, so that the reflected light (266, 268) is maximized.
11. System (100) according to one of the preceding claims, wherein the receiving basin (122, 202, 222, 244) has a foiled surface.
12. System (100) according to any one of the preceding claims, wherein the saltworks (120, 200, 220, 242) is arranged and designed to extract the salt from the salt-rich liquid and preferably to evaporate the liquid components of the salt-rich liquid (106).
13. System (100) according to any one of the preceding claims, comprising- 22 - a battery storage system electrically coupled to the photovoltaic device (150, 214, 236, 258) for storing electrical energy provided by the photovoltaic device (150, 214, 236, 258).
14. System (100) according to any one of the preceding claims, wherein the liquid desalination device (110) is arranged and designed to separate the base liquid into the low-salt liquid (104) and the high-salt liquid (106) by means of reverse osmosis.
15. Method for reducing the salinity of a base liquid, in particular seawater (102), comprising the steps: - Separating the base liquid into a low-salt liquid (104) and a high-salt liquid (106), - Receiving the saline liquid in a receiving basin (122, 202, 222, 244) of a saline device (120, 200, 220, 242), providing electrical energy for separating the base liquid with a photovoltaic device (150, 214, 236, 258), - wherein the photovoltaic device (150, 214, 236, 258) and the saltworks device (120, 200, 220, 242) are arranged and designed such that, during normal operation, light reflected from the receiving basin (122, 202, 222, 244) can be converted into electrical energy by the photovoltaic device (150, 214, 236, 258) in order to increase the power of the photovoltaic device (150, 214, 236, 258).