WO2011082777A1

WO2011082777A1 - Solar generator

Info

Publication number: WO2011082777A1
Application number: PCT/EP2010/007622
Authority: WO
Inventors: Dieter Seifert
Original assignee: Climate Interchange Ag
Priority date: 2010-01-08
Filing date: 2010-12-14
Publication date: 2011-07-14
Also published as: DE102010004195A1

Abstract

The invention relates to a solar generator for generating electric energy, designed and equipped such that said generator is suited, among other things, to generate water from the atmosphere at night by condensation processes. To this end, the condensation heat is discharged to the night sky by heat radiation. Part of the invention further relates to devices and methods for boosting the droplet formation and for increasing the obtained water amount, including the combination with the solar water desalination technique and the drying technique. The invention is in particular suited for large solar plants in arid and semiarid regions. Combining electric energy generation with fresh water generation and further functions enables measures for the prevention of desertification and the development of settlement areas with good living conditions, even in regions that were not readily habitable until then.

Description

solar generator

Reference to related applications

The present application claims priority to German Patent Application 10 2010 004 195.5, filed January 8, 2010, which is incorporated by reference in its entirety by reference. The invention relates to solar generators for the production of electrical energy.

There are devices known that use the photovoltaic power generated to drive cooling units condensed on the condenser surfaces water from the atmosphere. If the dew point temperature on a surface is undercut, the formation of dew is to be expected. The dew point temperature depends primarily on the proportion of water vapor in the atmosphere. For example, at a total pressure of 1 bar at the dew point temperature of 30 ° C, air may contain up to 27.592 g of water per kg of dry air volume in vapor form. When this is cooled at 30 ° C water saturated with air to 10 ° C, then only a vaporous water content of 7.7737 g per kg of dry air is possible in the thermodynamic equilibrium. This means that by cooling the at 30 ° C

saturated air at 10 ° C about 20 g of water as a liquid per kg of dry air can be separated. For water extraction from humid air therefore large amounts of air are cool, so that the equipment and the required electrical energy consumption for the operation of the cooling device are high. Well-known solar plants for the extraction of fresh water from sea or brackish water use evaporation facilities and the separation of the liquid water on surfaces, which are cooled by the ambient air or by the brine. As "brine" is here the water from which the fresh water is obtained, for example, seawater or contaminated water.Also in these cases, a great effort in relation to the amount of water obtained is required because the space-time yield of these facilities is low, so that the application on the required large scale could not yet be realized.

The object to be achieved with the present invention is the most cost-effective extraction of fresh water and, if necessary, of

Heat in conjunction with the cost-effective production of electrical energy.

This object is solved by the subject matter of the respective independent claims. Further advantageous embodiments are described in the respective dependent claims.

Especially in large systems for the production of electrical energy with the help of photovoltaic (PV) in arid or semi-arid areas, it is advantageous if the solar generator not only electrical energy, but also fresh water is obtained. The invention enables a combination of these two

Functions and other advantageous functions. It also allows applications in large solar systems, for example, in facilities for the production of electrical energy, which is optionally conducted over long distances or on a large scale for the production of hydrogen or for others

electrochemical processes is used. The connection of the electric Energy generation with freshwater extraction and other functions enables measures to prevent desertification and the construction of settlements with good living conditions even in hitherto hardly habitable regions.

An essential part of the invention is the advantageous use of the cooling power resulting from the radiation exchange with the night sky. This cooling power is particularly high in arid and semi-arid areas, because the radiation is high in clear night sky. In such areas, about 0.5 liters of water can be obtained as condensate per night per square meter of the area exposed to the clear night sky in the radiation exchange.

According to the invention, the solar generator has at least one means for shielding the solar module. This agent may either be an insulation, in particular a thermal insulation on the underside of a solar module or it may be

Be a reflector.

For a high sweetener, it is necessary that the condensing surface, that is, the surface which serves for heat radiation, have a high emissivity for long wavelength radiation (i.e., heat radiation at dewpoint temperature) and directly or via high reflectivity reflectors for long wavelength

Radiation is directed to the night sky ("night position"), so that the surface is not in the radiation exchange with the warmer environment (especially the ground) is a high emissivity of the glass cover to photovoltaic modules is given.However, in the usual arrangement of the solar modules With a heating of the module by the radiation from the warm environment on the back of the solar module to count, so that the cooling capacity is greatly reduced., In addition, for the formation of large Tastegen and for obtaining the amount of water is important that the dew drops formed by the condensation -Face removed, collected and protected against re-evaporation. It has been found that the placement of hydrophilic and hydrophobic areas on the condensing surface results in the formation of larger droplets and their drains. These areas may be in the form of hydrophobic wax stripes or wax dots.

For a solar system with photovoltaic modules (PV system), the module area is on the order of 8 m ² per kW of installed electrical capacity. When using reflectors for the concentrated irradiation of the solar modules, the area per kW is smaller. At a moderate concentration, under good conditions, per liter of installed capacity several liters of water per night can be obtained by generating oxygen at the solar module surface.

With modern irrigation methods requiring only a few liters per month to water trees in arid areas, especially in the early years of irrigation, it is possible to irrigate 10,000 trees per MW of installed capacity using appropriate technology. Suitable techniques include, for example, the "Xero Culture Technique," in which the young plant is planted in a plastic-covered trough.

On the side of the photovoltaic system that faces away from the sun, a forest of trees and shrubs can be created and drinking water can be made available to local residents if suitable technology is available to provide the water at a low enough cost.

The invention has the aim of the disadvantages of the known devices for

To overcome water extraction by using advantageous constructions of the

Solar generator, in particular of the solar module to be connected with advantageous measures for the recovery of water and possibly also for recovery of heat. The invention realizes a combination of this

Possibilities that have not been recognized and complemented by additional measures that are made possible by the inventive design, alignment and possibly movement of the solar generator.

It is noted that with the help of the solar generator, for example by

Solar cells in PV modules electrical energy can be obtained. The solar generator is according to an embodiment of the invention with a

horizontal pivot axis (for example, east-west orientation or north-south orientation) equipped so that a sufficiently accurate alignment according to the position of the sun can be done by a controlled drive. It is therefore preferred only the movement about a pivot axis, so that a simple

Elevation is sufficient. The tracking can also with a tilted pivot axis, z. B. in polar mount, done or with two axes. In principle, a rigid mounting of the generator is possible. This possibility is discussed in the explanation of FIG. 13. Also, a gradual alignment, for example, positions for summer, winter and a middle position for the time in the area of the equinox and comes into question. This case will be explained on the example shown in FIG.

It is essential that the solar generator can be aligned at night so that the solar modules are aligned directly or reflectors on the night sky, so that the formation of dew on the cooled surfaces of the solar module is made possible, and that also for the advantageous dissipation of Water is taken care of. Preferably, the reflectors are connected to the solar modules, so that they are in tracking their position with respect to the solar modules

maintained. This case is assumed in the described embodiments with trough mirror, wherein the trough mirror also serves to uniformly increase the irradiance on the modules during the day. But it is also according to the invention, if the mirror only for the shielding of the nocturnal Radiation from the warmer environment is used and may not be moved. Then, the mirror generally does not cause a uniform increase in irradiance during the day. The term "solar generator" is used not only for the individual solar generator for the sake of simplicity, but also for the entire system, which may consist of a plurality of individual solar generators arranged in parallel or in series. 1 to 12 it is assumed that a plurality of solar modules of a solar generator are arranged in two or three rows, two rows of which can be illuminated by a reflector in the form of a trough mirror, but in principle the invention is also suitable for

Solar generators without reflectors and for solar generators with a row or with more than three rows of solar modules. It is essential that the solar generator has facilities to win in addition to the production of electrical energy and water.

The use of a trough mirror has several advantages. Several solar modules can be arranged due to the trough mirror so that they face with their backs parallel or inclined and run in the night position, the condensate drops formed quickly. For this purpose, it is advantageous that in the night position, the perpendicular to the module surface (surface normal) with the vertical direction includes a sufficiently large angle ß (maximum 90 °). A trough mirror also allows an angle ß = 90 ° (parallel vertical module rows), so that the condensate formed runs very fast.

A special use of the trough mirror results when it is provided on the back with a structure described above, which is suitable for catching mist droplets. Then with fog the solar generator with the Tracking device are aligned so that the back of the trough mirror is optimally aligned with the fog flow.

The arrangement of parallel rows of solar modules makes it possible to form between the solar modules at least one longitudinal channel, which can be divided and which can be flowed through with air and optionally with water. The longitudinal channel can also serve to accommodate adsorbents, as will also be explained below. The longitudinal channel can be formed by being bounded on at least one side by solar modules. The

Heat dissipation on the back by the flow in the channel causes a

Improvement of the photovoltaic efficiency, because it decreases with increasing temperature.

It may be advantageous to arrange a hose or several hoses in the area between the solar modules in order to be able to realize various functions according to the invention simultaneously.

The arrangement of solar modules in opposing rows has the great advantage that the backs of the solar modules are not in the night position in the radiation exchange with the environment. The solar modules are

cooled together by the radiation of the module surface. In the area between the solar modules, a downwardly directed convection flow can also form on the cold rear sides, with which continuously moist air reaches the rear side of the solar modules, so that condensate can also be generated there.

A further advantageous possibility arises when a support tube is formed from plates which are used in lightweight construction, in particular sandwich panels, as well as hollow flat plates and bump plates made of aluminum, which are used for example for carriageway bridges. These plates can be connected in this way that they form a support tube with triangular cross-section. For connection, the longitudinal edges of the profiled sheets can be welded, riveted or screwed, for example, and profile bars can be used for the connection. The panels can be formed at the longitudinal edges so that they can be easily connected to each other, but also advantageous

Provide mounting options for the solar module rows. The attachment of the solar module rows on the support tube can be made so that a channel is formed between the support tube and each row of solar modules. In addition, the interior of the support tube can be used as a channel. When designing the attachment of the

Solar module rows on the support tube is ensured through openings and lines that the water, which forms as condensate on the back of the solar module rows, is deliberately dissipated.

If the solar modules have a sufficiently high strength, a separate support tube as a carrier of the modules can be omitted, because then the modules can be used as self-supporting elements of the support structure and can be held together by fasteners so that a support with a longitudinal channel is formed.

However, the solar modules can also be mounted on a truss, which then forms the support tube together with the solar modules.

The solar generator can consist of individual areas in which the

Longitudinal channel between the modules has different functions. Areas of the solar generator can also be equipped without PV modules or the PV modules can be replaced by hot water or hot air collectors, so that the solar generator can be adapted to the requirements of electrical energy, water and heat. This adaptation is facilitated by the modular design of the solar generator.

By irradiating the solar modules via a concentrating reflector can the extraction of electrical energy from the solar module can be increased.

After the cost of the reflector compared to the solar module costs are low, the concentration of solar radiation can significantly contribute to the cheapening of photovoltaic power generation. This is especially true when the

Concentration factor C is chosen to be such that conventional,

inexpensive solar modules can be used.

High concentration factors require special solar modules and, if necessary, complex cooling technology and precisely working trackers. In addition, it should be noted that the electric power of the solar generator at high concentration depends very much on the fluctuating intensity of the direct solar radiation, because the diffused portion of the solar radiation is not concentrated. Clouds cause large fluctuations in the generated electrical power at a large concentration factor. These fluctuations lead to a poor utilization of the connected system for the use of electrical energy. Therefore, a concentration factor less than 5 may be recommended, with the upper limit of using low cost solar modules being preferred.

Water can be obtained with the help of the solar generator according to the invention in many ways: By catching and passing on rain, by

Condensation of dew, by trapping mist droplets and by

Adsorption. Applications according to the invention of these processes are described in

Described below. For catching rain, the reflector is preferably placed perpendicular to the direction in which the raindrops fall. This will catch the

Rainfall maximized. Channels or channels and pipes can be used to divert the water to the water reservoir. The trough mirror itself can serve as a gutter. This is particularly advantageous for large amounts of water to be derived selectively, as is the case with heavy rainfall. For a quick drain too At low water flow is a groove at the junction of the two

Reflector parts advantageous. In solar generators with inclined axis, for example in the polar mount, a slope of the channel is already given. Also in the other cases, it is advantageous to realize over a sufficiently long range of the generator a clear inclination, for example, of one or a few mm per meter, as is also customary in gutters. In order to achieve drainage of the water, however, only the gutter can be arranged inclined. To improve the discharge of the recovered water, it is advantageous to equip the channel with a surface that is not wetted if possible, so that small amounts of water bead off quickly.

To generate dew on the solar generator surfaces, in particular on the solar module surfaces, the solar generator is aligned at night so that these surfaces as completely as possible directly and / or over a reflector in the radiation exchange with the night sky. In a preferred embodiment of the solar generator then the solar modules are at least approximately aligned vertically, so that the condensate runs downwards by gravity and can be collected with the gutter of the reflector. An advantageous possibility for obtaining drops on the back of the reflector and the back of the solar modules is to provide the surface with a structure of hydrophilic elevations and intervening hydrophobic valleys. The front of the reflector and the front of the solar module, so the active side of the reflector and the solar module can be provided with a structure that causes the formation of droplets and an increased drainage of the drops. For this purpose, for example, serve transparent, hydrophobic coverings or alternately hydrophilic and hydrophobic strips are mounted on the surface. This measure can be realized with coating technologies. An outflowing drop absorbs the drops lying on its way, so that its drainage trace of water develops and thus drops are particularly effective, which develop in the upper part of the surface. It may therefore be advantageous to provide an extension at the top of the solar modules, which is provided with a surface for heavy condensate formation and intensive droplet discharge. These

Extension of the solar module surfaces can be made mainly of metal, plastic or glass. The surfaces should have a high emissivity in the long-wave range of the radiation. By a surface structure with alternating hydrophilic and hydrophobic areas, the formation of droplets can be enhanced. The surface of the modules can then be without special coating. However, a hydrophobic coating or coating with hydrophobic stripes or dots would be beneficial. Another possibility to remove the condensed liquid from the condensation surface, is to apply water by means of a pump in the upper part of the condensation surface and repeatedly rinse the condensation surface. For this purpose, a distribution device, for example, an overflow channel along the upper edge of the condensation surface or water nozzles to install.

If necessary, the tracking device can be used to the

Periodically swing solar generator so that the condensate drops drain. By means of shaker devices mounted on the generator, shocks and vibrations can be generated to increase the drainage of the condensate.

In order to further increase the amount of milk, the moisture content of the air at the solar generator can be increased at night by heating brine in a shallow basin during the day and moist air over this warm one during the night

Water supply is supplied to the longitudinal channel of the solar generator. For this purpose, a water desalination plant can advantageously be connected to the solar generator. The water desalination plant can consist of a flat brine basin with an oblique cover in the known construction and a gutter for the condensate draining off the cover. The invention makes it possible for the high energy radiated onto the solar generator - that of the photovoltaic only to a small extent into electrical energy

is converted - to use to produce the largest possible amount of fresh water. For this purpose, air in the longitudinal channel can be heated and used for heating and evaporation of the water. The warm air stream from the

Solar generator can not only the desalination plant or a

It can also be the brine inflow to desalination plant as a covered channel are formed, in which the air flow is passed, so that it covers the inflowing brine. The covered channel can be advantageously equipped with flow baffles to increase the heat exchanging and water evaporating area. By the

Air circulation raises the water temperature during the day. At night, a large amount of water can be condensed throughout the system.

The water desalination plant may have one or more sections in which the supplied brine for cooling the humid air flow in the

Desalination plant is used, wherein the brine is preheated. At this cooling device and on the transparent cover of the remaining part of the desalination plant condensate can be obtained during the day.

Another way to increase the amount of condensate is to the longitudinal channel between the solar modules, possibly with the help of hoses in this longitudinal channel, the day with brine from the desalination plant to

flow through and warm them. The heated brine is in the

Water desalination plant returned. Water can also be obtained by attaching fine-meshed nebulizer traps to the rear of the reflector. For this purpose, the existing holder for the reflector can be used. The solar generator can be pivoted so that the flow with the fog droplets effectively comes into contact with the network. For this purpose, an orientation of the network across the direction of flow will generally be advantageous. The air deflection on the reflector can cause a reinforcing effect in the droplet deposition.

Water from the atmosphere can also be obtained by adsorption and desorption processes. For this purpose, for example, the longitudinal channel with the

Adsorbent are filled, which is loaded with water at night and desorbed during the day with the aid of the supplied heat and fed to a memory.

For example, zeolites can be used as a long-term storage of solar energy for supplying heat in the form of a cheap adsorption agent that is available in large quantities

Niedertemperarurbereich be used. In this case, the absorbent can be used in the longitudinal channel in the space between the solar modules and be traversed with air. When wet air is introduced into the longitudinal channel at night, water is adsorbed and dry heated air is released because the heat of adsorption is released to the airflow. This airflow can be used at night for heating purposes. The loading front moves through the adsorbent, creating a water-saturated layer of zeolite.

During the day, at elevated temperatures, solar radiation from the solar generator can regenerate the absorbent by desorbing the water and creating a flow of air laden with desorbed water. From this stream of moist air is separated by cooling water, for example with the help of a Kaltwassser reservoir, the for example, was cooled during the night with another part of the solar generator or with other means for heat dissipation.

The heat from the solar generator can also be used, for example, to load day or season storage. Then, the longitudinal channel of a heat transfer medium, generally water, flows through, which gives off its heat to the memory. Or it is desorbed heated air from the solar generator adsorbent storage, so that when heat demand by adsorption of water, the heat of adsorption can be used.

The irradiation on the solar generator during the day can also be used to heat air for other desorption processes. Particularly suitable for the use of heat are processes that do not require a high temperature,

For example, drying of agricultural and forestry goods and, where appropriate, of bricks, if they are suitable for curing at these temperatures, and for Desoptionsprozesse.

For a long life of the solar generator in regions where strong sandstorms must be expected, the invention allows a position of the reflector, wherein the reflector surface and the solar modules against the

Damage caused by the grains of sand are protected. For this purpose, the solar generator is pivoted so that the (concave) receiver side is directed downwards. In this case, the solar generator also has a low air resistance, so that the

Burdens of storms are reduced.

The measures for condensate formation and for the drainage of the condensate droplets are at the same time also advantageously effective in the cleaning of the surfaces of dust deposits on the solar module surfaces. To explain the invention serve the drawings, which are described in more detail below to be discribed. Show it:

1 shows a cross section through a solar generator in an operating position during the day.

2 shows a cross section through a solar generator in the night position.

3 is an oblique view of a solar generator in the night position;

4 shows a cross section through a triangular arrangement with three rows of solar modules.

Fig. 5 is a diagram for the operation of a solar generator for the production of

Condensate at night in conjunction with a simple solar

Water desalination plant;

Fig. 6 is a plan for explaining various functions of a solar generator; Fig. 7 is a diagram for operating a solar generator during the day in

Connection with a desalination plant;

8 shows a surface structure for the accelerated formation of droplets on the solar module upper side;

9 shows a surface structure for the accelerated formation of drops on the rear side of the reflector, the rear side of the solar modules or an extension of the solar modules;

Fig. 10 is a schematic representation of a drive and a solar generator in position during the day;

Fig. 1 1 is a schematic representation of the drive and a solar generator in position during the night or in the rain;

Fig. 12 is a schematic representation of the drive and a solar generator in the position in the morning;

13 shows a solar generator in a rigid mount;

14 shows a solar generator which is only to be aligned at long intervals; Fig. 15, 16 and 17 extensions of the solar modules in the form of surfaces in cross section

Fig. 18 and 19 extensions in the form of needles in cross-section and in side view. The figures show preferred embodiments in schematic form, illustrating the essential points for the explanation of the function. For simplification, the term "solar modules" is used for the receivers of the solar radiation, preferably PV modules

Illustrate the invention without intending a limitation of the invention to the illustrated embodiment.

Fig. 1 shows the arrangement of solar modules in two rows la and lb, a reflector in the form of a trough mirror, consisting of two reflector parts 2a and 2b, which is moved with the solar modules and reflects the direct solar radiation to the solar modules. The solar modules are aligned in the illustrated case parallel to the irradiation direction of the sun and are illuminated by the reflector with a concentrated irradiation. However, the solar modules can also be arranged obliquely to the center plane of the reflector. The solar generator is tracked by a pivoting device, such as a gear or chain transmission (not shown), in a known manner to the level of the sun. The reflector may advantageously be shaped so that the irradiance of the

Solar module surface is the same everywhere as possible. In addition to the law of reflection, the condition is to be observed that the ratio of the distance dy of the incoming solar beams to the distance dx of the reflected solar beams on the solar module is constant:

dy / dx = 1 / C

where C is the concentration factor. For explanation, two solar beams are shown as arrows 3. The effective width of the reflector (i.e., the transverse to the

Irradiation direction measured width) is then larger by the factor C than the width of the solar module. The angle et between the median plane and the

Solar module surface affects the shape of the reflector. The angle α is also defined as the angle between the surface normal of the solar module surface and the surface normal of the center plane of the solar generator, between the Solar module rows. The angle α of the two solar module rows and also the

Concentration factor can be chosen differently, even if the reflector is adjusted. Fig. 1 is drawn with C = 2 and α = 0. The angle α is shown in FIG. 4. The angle β between the surface normal of the solar module surface and the vertical is illustrated in FIG. By tracking the position of the sun and the concentration can be optionally a cheapening of

photovoltai see electricity generation and it can be additional

Realize functions of the solar generator without much extra effort. The relatively low concentration does not require high precision reflector and tracking. By extending the reflector over the theoretical

In addition, deviations from the theoretically required shape and orientation can be largely compensated.

Fig. 2 shows an arrangement according to FIG. 1, but in the night position, d. H. in the position for advantageous energy radiation for water production at night. In the illustrated case, the angle α = 0 and the solar modules are therefore vertically aligned and are directly above the reflector and in the

Radiation exchange with the night sky. As a result, the temperature on the solar module surfaces may drop below the dew point and water may precipitate in the form of drops. Due to the vertical position of the solar modules la and lb, the drops can drain quickly. At the reflector, a channel 4 is arranged to conduct the recovered water. The water that condenses on the outside of the solar modules, runs down or drips from the solar modules down and is collected by the channel 4 and forwarded. The water condensed on the back of the solar modules can be routed in the longitudinal channel or can also be led into the channel via openings. The rows of solar modules face each other and this prevents heat exchange with the warm environment. In order for condensate to form on the inside of the reflector, the reflector would have to be insulated on the outside to absorb the heat from the warm environment and to reduce convective heat transfer. It is essential that the function of the reflector is maintained even for the long-wave heat radiation.

For supporting the solar modules la and lb and the reflector parts 2a and 2b, the preferably tubular side member 6 is used. However, the longitudinal member 6 can also be designed, for example, as a truss or partially formed from the solar modules.

At the solar module rows l a and lb above extensions 7 are attached, which by a high emissivity and optionally by a

Surface structure with alternating hydrophobic and hydrophilic areas for the formation of condensate droplets are particularly suitable. It is outlined a support structure 8 for the reflector 2. This support structure is preferred with the

Side member 6 is connected, so that the reflector moves with the solar modules. The connection between the support structure and the longitudinal member is not shown for clarity.

Fig. 3 is an oblique view of the solar generator. The length of the solar generator with the solar modules 1 can be very large. In order not to let the load on the side member 6 become too large, it is stored at shorter intervals. It is shown a support 9 with support 10.

In Fig. 3, a longitudinal channel 5 is shown, which is bounded on two sides by the solar module rows la and lb. This design requires little effort for the longitudinal channel and results in a low heat transfer resistance between the

Solar module and the medium in the longitudinal channel. There are a variety of ways to use the longitudinal channel: as a tube for cooling moist air to collect condensate at night, to heat air or water during the day or to absorb adsorbent. The longitudinal channel is accordingly closed, for example, with sheets or by plastic or fabric webs or with hoses, for example made of plastic film or fabric.

At the bearing points of the solar generator, the longitudinal channel over

Connecting cables are bridged or the longitudinal channel is connected in the area of storage to a stationary line system (duct or pipe system). In Fig. 3, a connecting pipe 1 1 is sketched for bridging the bearing at the rear bearing.

In solar generators with approximately horizontal axis of rotation is achieved by a slight inclination of the channel 4 relative to the horizontal that the water draining or dripping from the solar modules and from the other surfaces, specifically tapers the line system.

Fig. 4 shows the cross section through a triangular arrangement of three rows of solar modules l a, lb and lc. The support tube 6 is located in the interior of the triangular arrangement and consists of profiled sheets 12 which are connected to the longitudinal edges of profile bars 13. The profile bars 13 connect the profiled sheets and can serve for the attachment of the solar modules la, lb and l c. By fastening the solar modules to the sides of the triangle at a distance from the profiled sheets 12 of the support tube 6, a channel 5a, 5b and 5c is formed behind each row of solar modules. In addition, the interior of the support tube can be used as a channel. For the drawn arrangement in the form of an equilateral triangle, an angle α = 30 ° results between the

Center plane and the solar module surface, which is entered in Fig. 4. If deviated from the equilateral arrangement, other angles a result. In particular, angles in the range of 0 ° to 60 ° are suitable. As with the

Arrangement with α = 0 ° in Figures 1 to 3, also has the triangular arrangement in Fig. 4 has the advantage that the back of the solar modules is not in the radiation exchange with the warm environment.

Fig. 5 includes a schematic for operation of the solar generator to recover condensate during the night in conjunction with a desalination plant. From the water desalination plant 14 with the brine basin 15 moist air is removed by means of the blower 16 and fed to the longitudinal channel 5 of the solar generator. The moist air comes into contact with the cold solar modules so that condensate forms. The condensate flows down the inside of the solar modules, is discharged into the gutter or directly from the longitudinal channel and in

Fresh water tank 17, an open or a covered or closed container collected. It can be used, for example, for the drip irrigation of trees 18 by means of a pump 19. Also in the

Desalinator 14 recovered condensate, which forms on the transparent cover 20 and drains into the fresh water channel 21, the

Fresh water tank 17 are supplied.

6 contains a schematic representation of solar generator applications according to the invention, which is illustrated above for 4 different application methods, designated A, B, C and D:

In the function A, the mode of operation described in FIG. 5 is outlined. Here, the fresh water tank 17 is in the lower part of a building 22. Zur

To simplify the illustration, it is assumed that a living area 23 and a drying area 24 are arranged one above the other in the building, wherein the drying area can be used for drying of agricultural or forestry or industrial products and for heat storage. There are many ways to rearrange these functional areas. In the case shown, the supply of cold water can be particularly easy to cool the living area 23 at high ambient temperatures, for example, by water from the

Fresh water tank 17 through a heat exchanger (not shown) is pumped, through which the air to be cooled is passed. And it may optionally be used in the drying area stored heat for heating the living area. In order to avoid an uncontrolled heat transfer, the floors can be separated with insulating layers. Through a targeted Air exchange between the functional areas via controllable connection channels or heat exchangers thus the living area can be advantageously cooled or heated as needed. In the position of the solar generator according to function B in Fig. 6 is the

Reflector 2 horizontally placed to get the largest possible catchment area in the rain. The rainwater is fed to a large collecting salary 25, for example a pool or a reservoir. In the function C in FIG. 6, the solar generator is aligned with the sun, so that the solar modules are irradiated in the intended manner via the reflector from the sun and generate electrical energy. In this operating position, the longitudinal channel 5 can be flowed through and heated. The heated air can be used, for example, for drying products. It is schematically the supply of heated air in the drying room 24 in the attic of the

Building 22 shown. Through heat-storing masses in this area can be ensured that the living space can be supplied with warm air if necessary. In the function D, the longitudinal channel 5 is flowed through by the brine and thereby heated by the heat generated at the solar modules. It is assumed that the brine is removed by means of the pump 26 of the desalination plant 14 and heated again supplied. This will increase the performance of the

Increases the desalination plant and it creates a supply of warm water, which ensures even at night for a high absolute humidity in the desalination plant. If it is sufficiently large systems, it may be advantageous to operate one part of the solar generator with the function C and another with the function D. However, it can also after the emptying of the longitudinal channel 5 of the function D to the function C change. In Fig. 7, the connection of the solar generator with a desalination plant 14 is shown, which consists essentially of the brine tank 15, the evaporation part 27 and the condensation part 28. In the condensation part, the brine basin 15 is covered with a roof 29 in the case outlined, which is equipped with channels through which the incoming brine is passed. The brine absorbs the heat of condensation of the condensing on the bottom of the roof 29 fresh water and the incident solar radiation. The thus preheated brine flows into the brine channel 30 and is supplied to the brine tank 15. The condensed on the underside of the cover 20 and the roof 29 fresh water runs into the fresh water channel 21 and is fed from there for storage or use. The pre-heated brine can be distributed, as in the case outlined above, with a pump 31 prior to entry into the brine basin 15 onto a baffled inlet channel 32 to produce a large surface area for evaporation. The temperature in the evaporation part 27 is increased during the day by the solar radiation which enters through the transparent cover and by the circulation of the air through the longitudinal channel 5 of the solar generator by means of the blower 16. In Fig. 7 is the

Outlined situation by day. At night, the solar generator of Fig. 3 is brought into the re-adjustment, so that fresh water from the circulating moist air in the solar generator can condense. The supply of brine to the roof 20 is advantageously interrupted because the radiation of the roof 20 can serve for heat dissipation during the night, so that even in this phase in the condensation part 28 of the desalination plant 14 fresh water can condense.

Fig. 8 shows a surface structure on a surface 35 for improving the formation and drainage of drops from the top of the solar modules and the extension 7 (Fig. 2) and the surface of the reflector. The rows of hydrophobic dots 33 or hydrophobic lines 34 facing toward the

desired droplet path are arranged, causing the condensed water forms drops that run fast. Permanent hydrophobic dots or lines can be obtained, for example, by means of known methods for coating or for Printing of glass or aluminum and be developed by nanotechnology developed process. It is generally not necessary to provide the entire surface with the rows of hydrophobic dots or hydrophobic lines, because it mainly depends on the formation of large enough drops, which then run off automatically. Thus, it may be economical to attach the structure only to the extension 7 (Figure 2).

FIG. 9 outlines a surface structure which is suitable for the rear side of the reflector and for the rear side of the solar modules and which is suitable for accelerated formation of drops 36. In this case, hydrophilic crests 37 are arranged in hydrophobic intermediate spaces 38, so that drops form in the hydrophilic area, which also carry along further water on their way. Sketched is a way to create the surface structure in the hydrophilic glass beads pressed into a hydrophobic plastic matrix

or are melted down.

Fig. 10 shows a schematic representation of a drive of the solar generator, wherein the solar generator is in a position during the day. He is aligned according to the variable level of the sun. As drive for the adjustment of the positions and the tracking on the ridge of the sun a chain drive with a chain 39 is sketched. The pinion 40 of

Chain drive is driven by a not shown drive in a known manner via the shaft 41. The sprocket 42 is attached to the support tube 6 and is brought by the chain 39 in the desired position

In Fig. 1 1, the solar generator is shown in the night position or in the position when it rains.

In Fig. 12, the solar generator is shown in one of the position in the morning, in which the back of the reflector 2a and 2b for water harvest from the morning Dew should serve. The surface structure on the back of the

Reflektors act advantageous according to FIG. 9. Alternatively, or in addition, a net 43 may be attached to the support structure 8 from which water is collected and discharged. The optimal orientation of the reflector depends mainly on the terrain of the site and the

Flow velocity of the mist from. With gutters 44 and 45, the recovered water is collected.

In Fig. 13, a solar generator is shown without tracking. In order to promote the condensation of water, an extension 7 is mounted above the solar modules 1, which is similar to that described in FIG. 2, equipped for the formation of condensate drops. So that the solar modules 1 and the extension 7 are sufficiently cooled by the nocturnal radiation, the back of the

Solar modules and the extension against the heat from the environment protected by a thermal insulation 47. This heat insulation can for

Example in a known manner from a radiation shield 48 from

Aluminum foil in a cover 49 exist. The radiation insulation can be carried out in such a way that undesired heating of the solar modules during solar radiation is avoided. For this purpose, in particular an upwardly directed convection current at the back of the solar module can be made possible through openings.

Fig. 14 shows a solar generator, in which the solar modules 1 with a trough mirror in the form of two laterally mounted reflectors 2a and 2b. The solar generator can be aligned at long intervals, but it is at least twice a year, for example, only from the winter to the summer position to align. For this adjustability storage on rollers 50 is drawn. The rear side of the solar modules and the reflectors is, as described in FIG. 13, protected by a heat insulation 47. The insulation can also be designed as a longitudinal channel, which are used according to the functions described in Fig. 5 can.

15 and 16 show extensions in the form of surfaces 7a and 7b above the solar modules, which are designed to permit air flow along the rear sides of the PV modules during the day and to allow only a slight flow in the night position to minimize heating by convection. For this purpose, a gap defined by the stop 51 is open on the day (FIG. 15) between the surfaces 7a and 7b of the extension, for example by the surface 7b being moved downwards by the weight force. In the night position (FIG. 16), the surface 7b can rest against the surface 7a and thereby close the gap. The surfaces 7a and 7b can advantageously be provided with structures according to FIGS. 8 and 9.

Fig. 17 shows a sketch of a vibrator equipped with an electromagnet 52 which can briefly push the surfaces 7a and 7b apart to cause the dewdrops to drain. With vibrators can also the extension 7 of FIG. 13 and the described reflectors of

Solar generator to be equipped for the droplet drain.

Fig. 18 and Fig. 19 show extensions in the form of needles 53, the dew and fog drops increase and thereby bring drops to drain over the surface of the solar modules 1 a and 1 b. To increase the droplets, hydrophobic lines 54 according to FIGS. 8 and 9 can be arranged on the needles. The hydrophobic lines may merge at the lower end into a hydrophobic region at which the drops are dammed and forced to grow before draining. In Fig. 19, this hydrophobic region is represented by lines 55.

The extensions are preferably made of light-resistant plastic. By sufficient elasticity of the needles can be provided for the movement of the needles, through which the drainage of the drops is promoted. The extensions can be used as kits for attaching to existing ones

Solar modules are designed so that they can also be retrofitted. In connection with also subsequently retrofittable components, the invention can also be used in existing PV systems.

Claims

claims

1. Solar generator comprising:

a solar module for the production of electricity,

Means for shielding the solar module so that the solar module during the

Night is shielded from radiation from the warmer environment, and means for catching dew, which forms at the solar generator.

2. Solar generator according to claim 1,

wherein the shielding means is a reflector in the form of a trough mirror for reflecting the solar radiation onto the solar module.

3. Solar generator according to claim 2,

wherein the angle (a) between the surface normal of the trough mirror associated solar module surface and the center plane of the solar generator in the range of 0 ° to 60 °.

4. Solar generator according to one of the preceding claims,

wherein the solar generator further comprises a tracking device for the

Orientation of the solar generator during the day on the sun and for the alignment of the solar generator on the night sky.

5. Solar generator according to one of the preceding claims,

wherein the surface of the solar module and / or the surface of the

Solar module mounted extensions is provided with a structure of hydrophilic and hydrophobic areas.

6. Solar generator according to one of the preceding claims,

further comprising a pump and distribution means, so that at a

Surface formed dew can be rinsed off by water.

7. Solar generator according to one of the preceding claims, further comprising a vibrating device, so that dew drops formed on a surface can be caused by targeted vibrations to drain.

8. Solar generator according to one of the preceding claims,

wherein the means for collecting dew is at least one of the group consisting of gutter, pipe, hose, open container and covered container.

9. Solar generator according to claim 8,

wherein the solar module forms part of the means for catching dew.

10. Solar generator according to one of the preceding claims,

wherein the solar module is a supporting part of the support structure of the solar generator.

1 1. A method of using the solar generator according to any one of the preceding claims, wherein the method comprises the step of using the means for

Containers for heating air and / or adsorbents.

12. A method of using the solar generator according to claim 1 1,

wherein the heated air is used for drying or curing goods or for desorbing.

13. A method for using the solar generator according to one of the preceding claims,

wherein the solar generator is operated in conjunction with a water desalination plant, wherein air which has been moistened in the water desalination plant is passed to the solar generator and / or air which has been heated in the generator, the desalination plant is supplied.