WO2015199563A1

WO2015199563A1 - Geoengineering installation for producing renewable energy and water

Info

Publication number: WO2015199563A1
Application number: PCT/PL2014/050064
Authority: WO
Inventors: Antoni Kostka; Mariusz Paszkowski
Original assignee: Vis Inventis Spolka Z O.O.
Priority date: 2014-06-23
Filing date: 2014-10-13
Publication date: 2015-12-30
Also published as: PL237442B1; PL408641A1

Abstract

Canopy (1) constitutes a system for the radiant cooling of air masses held between the ground and canopy (1) and consists of an optically selective structure letting infrared radiation emitted by the ground through to escape into outer space, but reflecting visible, ultraviolet and near infrared solar radiation, both directly incident and scattered by the atmosphere. The canopy (1) is divided into cells (2), depending on the design, of different cross-section geometries,preferably hexagonal (honeycomb), vertical or sloping northward (N) in the northern hemisphere or southward (S) in the southward hemisphere, preferably at 45°, or galleries running W-E, while the walls of cells (2) forming part of the canopy are stretched on a mechanically strong skeleton that makes them rigid, or the rigidity of canopy (1) is ensured by the pressure of a gas filling cells (2).

Description

Geoengineering installation for producing renewable energy and water

This invention concerns a geoengineering installation for producing renewable energy and water from atmospheric air, which converts kinetic and thermal energy from an artificially produced katabatic wind and passively condenses water contained in atmospheric air. This installation also forms a passive, integrated system for microclimate control, thus enabling the above functions to be performed and plants having higher thermal and humidity requirements to be cultivated.

Natural air movements caused by pressure differences found in nature are used as a way of generating so-called renewable energy. Wind drives wind turbines and windmills, for example. A special type of wind is a slope wind blowing downhill (mountain breeze, katabatic) or uphill (valley breeze, anabatic), which changes its direction at daily intervals. On a sunny day, mountain slopes heat up, hot air masses above them rise, while at night the air above slopes is cooler than in valleys and because it is heavier, it flows down the slope. Particularly strong katabatic winds blow when the sky is clear, when the air above slopes is cooled by the ground radiating its heat into outer space. In certain conditions, katabatic winds can blow round the clock. This happens when mountain slopes are covered with snow or glaciers and there are no clouds in the sky. In such conditions, solar radiation is not absorbed due to the high albedo of snow, which is simultaneously radiantly cooling due to its high emissivity in the far infrared spectrum, thus cooling the air directly above it. An anabatic or katabatic air movement can also be caused artificially, by intentionally heating or cooling it. Solutions are known which make use of the force of the rising hot air (an updraft) or the falling cold air (a downdraft), which in both cases drives a correctly arranged system of turbines producing electricity.

An example of a machine generating energy this way is the so-called Solar Tower or a Solar Mountain. It is made up of a chamber (collector) covered with a canopy transparent to solar radiation, spread over a relatively large area, in which the air is heated by the sun, and a duct leading up from this chamber. The heated, lighter air escapes from the chamber through the duct, in which it drives a turbine connected to an electricity generator. The drawback of such solutions is that the energy driving the devices flows into them only during the part of day when the sun is sufficiently high above the horizon. Other drawbacks of solar towers is their suitability only for regions in which the majority of days are sunny and the large footprint of the collector.

A method and a device for generating electricity using a regulated flow of air in areas where it is of a low relative humidity is known from description US 3 894 393. Trapped masses of air are cooled below the surrounding temperature by evaporating water fed from the outside at a certain height. These masses of air are isolated from their surroundings by a high throughput duct. As a result, the heavier, denser air flows down the duct while the kinetic energy of the falling mass is transformed into electricity by turbines and a generator.

A method of producing electricity in areas where the air is of low relative density, using a natural channel in the form of a canyon open at the top and naturally closed at one end is known from description US 4 801 81 1. The other end of the canyon is closed with a partition whose base contains a turbine connected to a generator. The air in the canyon is cooled by spraying water at its entrance, as a result of which it flows down toward the base of the partition and the turbine. This partition is preferably designed as a flexible curtain blocking the outlet of the canyon, hanging from elements which are suspended from a rope anchored to two towers built on canyon edges.

A machine generating electricity using a set of turbines driven by cooled air falling down a vertical cylindrical building is known from description US 6 510 687. This system is known as a Downdraft Energy Tower. The air inside the building is cooled by spraying water, pumped from a ground-level tank, in the upper part of the installation. The application of this energy generation method is restricted by the necessity of locating systems close to reservoirs of water.

A canopy stretched above a natural canyon and forming an air duct with an upper inlet and a lower outlet is known from description US 4 481 774. Sunlight penetrates through the canopy and heats the air in the duct, making it flow up the duct. The air released from the duct can drive a wind turbine. The canopy is produced of a material transmissive to solar radiation and has a modular design. Individual panels of the canopy are made of two sheets of plastic separated by a cell containing air, compressed air or a lighter-than-air gas. These panels are connected with lengthwise joints. The canopy has a non-reflective coating which makes it easier for the solar radiation to penetrate inside but blocking it from reflecting off the collector to the outside. The outgoing longwave radiation of the Earth, whose wavelength is longer than that of the solar radiation, is blocked by the canopy covering.

The change of air temperature also influences its relative humidity. Cooled air becomes relatively more humid while heated air - drier. Water vapour condensation is used in various machines which passively or actively utilise the increase of relative air humidity to produce fresh water.

In addition, devices which utilise natural radiant cooling for air conditioning or to chill water or foodstuffs are known. A method of producing ice based on nocturnal radiant cooling has been known for a long time - water held in a shallow vessel is appropriately insulated from the surroundings. As a result of heat emission, this water freezes at night even though the air temperature does not fall below 0°C.

There is a need to construct a system of low cost but simple operation which would generate energy passively, in a renewable way and allowing fresh water to be obtained as an added benefit. The geoengineering scale of the proposed system would allow satisfying mass demands for energy, food and fresh water while improving the quality of life in extreme climates by lowering the temperature and increasing the humidity of the microclimate.

This system would work by converting the mechanical energy of the flux of falling, cooled air into electricity using a wind turbine and a generator. Air temperature would be lowered by using radiant cooling, and not using the negative evaporation heat of sprayed water as in downdraft installations.

A geoengineering installation for obtaining renewable energy and heat from atmospheric air envisaged in this invention includes an insulated space naturally or artificially demarcated in the terrain, particularly in a depression on a slope, in a valley, in a canyon or on a plateau, insulating from the atmosphere with a canopy and having an air inlet as well as an outlet. Within this space, cooling air masses makes them dislocate, while the air outlet is connected to ducts routing the cooled air into an energy conversion assembly, in particular to an electricity generator.

The solution envisaged in this invention makes use of three basic, natural phenomena. The first is the wind, and in particular a slope wind caused by a difference in the density and temperature of air masses. Another phenomenon is that the relative humidity of air rises when its temperature drops down, until condensation occurs after the dew point is exceeded. The last phenomenon is radiant chilling caused by the loss of energy due to radiating long-wave thermal rays into outer space, which is not compensated by the delivery of short-wave solar radiation.

The essence of the solution envisaged in the invention is that the canopy constitutes a system for radiantly cooling air masses held between the ground and the canopy, and consists of an optically selective structure through which the infrared radiation emitted by the ground escapes into outer space, but which reflects visible, ultraviolet and near infrared solar rays, whether directly incident or scattered by the atmosphere.

The canopy is divided into cells which, depending on the design, have different cross-section geometry, preferably hexagonal (honeycomb), vertical or sloping northward (N) in the northern hemisphere or southward (S) in the southward hemisphere, preferably at 45°, or galleries running W-E, while the walls of cells forming part of the canopy are stretched on a mechanically strong frame that makes them rigid or the rigidity of the canopy is ensured by the pressure of a gas with which the cells are filled.

The walls of cells forming part of the canopy are made of a flexible, strong polymer coated with a mirror-like layer reflecting long-wave and solar radiation, or retro-reflective for directly incident solar rays, as a result of which the cells function as a light pipe for infrared radiation.

The walls of cells designed as reflective are coated with a metallic layer of aluminium or silver shielded by a transparent protective layer, preferably of aluminium oxide or a glassy fluoropolymer, which will additionally prevent dust from settling due to hydrophobic properties of this layer; for the retro-reflective coating, it is allowed to use retro-reflective prismatic or spherical foil, preferably coated with a hot-mirror-type low-emissive and low- absorbative coating. Cells can be closed at the bottom with covers stretched over a rigid or flexible frame, preferably vertical (in the case of skewed cells or galleries) or sloping (for vertical cells) in order to evacuate the dust and precipitation falling on the canopy, whereas the bottom covers of cells are built of an optically selective material transmissive to far infrared radiation (8-12 μιη), but reflecting (wholly or partly) solar rays from the UV-VIS and NIR ranges, both dispersed and directly incident, or from a material opaque to infrared and having the features of an absolute black body for FIR, i.e. one having high emissivity and absorbency in this spectral range.

Cells are additionally shielded with horizontal covers, preferably forming a part of a sheet covering more than one cell, and preferably the greatest possible number of cells, made of an optically selective material transmissive to far infrared radiation (8-12 μιη), but reflecting (wholly or partly) solar rays from the UV-VIS and NIR ranges, both dispersed and directly incident.

The column of gas in open cells is stabilised by an air trap, whereas the lower inlet of cells should be shaped as a Winston cone or a complex paraboloid with walls that are reflective to FIR radiation as well.

Cells may be fitted with flaps for adjusting the amount of long-wave radiation passing through the layer and protecting them from unfavourable weather, which flaps would be closed individually or mechanically interconnected.

Covers may be made of various materials presented below.

The material of the covers is optically selective, is a film several μπι thick, pressed together or bonded of ZnS nanograins sized about 300 nm or of ZnS nanofibers, covered with a non- reflective moth eye microstructure with the separation, module and height of about 1 μπι, intended to dampen reflections of 8-12 μπι wavelength radiation, additionally protected from moisture by a layer of amorphous fluoropolymer or AI2O3 up to 1 μπι thick, transmissive to infrared radiation.

The material of the cover is a film several μπι thick, pressed together or bonded of NaCl nanograins sized about 300 nm or of NaCl nanofibers bonded with an amorphous polymer, covered with a non-reflective moth eye microstructure with the spacing, module and height of about 1 μπι, intended to dampen reflections of radiation with the wave length of 8-12 μπι, additionally protected from moisture by a layer of amorphous fluoropolymer or AI2O3 up to 1 μπι thick, transmissive to infrared radiation.

The cover material is a foil of foamed tetra fluoropolymer (a microfoam or an airgel), preferably featuring a fractal, hierarchical pore structure, with the total material thickness no greater than 3 μπι.

The cover material is a foil of ultrapure mono- or polycristalline silicon, up to 50 μπι thick, transparent to long-wave radiation but reflecting solar radiation, covered with a microstructure reflecting visible light, but anti-reflective to the FIR. The cover material is a sheet of a material opaque to long-wave radiation, of very high absorptivity and emissivity for this radiation and high diffusive reflectivity to UV-VIS and NIR radiation, although it may be partially transmissive to this range (silicate milk glass (i), foamed glass (ii), foamed polymers resistant to photodegradation (iii), non-woven mat or a glass fabric of silicate (iv), boron/silicate (v) or boron/lithium glass (vi)).

The cover material is a sheet of finely foamed (less than 1 μπι) high or medium density polyethylene (HDPE or MDPE) stabilised against IV radiation, transmissive to long-wave radiation and reflective to solar radiation, preferably with a surface microstructure reflecting visible radiation but anti-reflective to FIR.

According to the invention, it is possible to generate a controlled katabatic wind by employing a selective climate partition installed on a suitable land relief feature. This canopy makes it possible to radiative chill the covered area and air masses between the ground and the canopy. Cooled masses of air, in the form of a katabatic wind generated in a controlled fashion, are routed into an appropriately laid duct or a set of ducts and drive air turbines located at their outlet. The operation of this installation also produces fresh water from water vapour condensing in the cooled air.

The benefits of this solution consist in creating microclimatic conditions better than those of the surrounding climate. The presented installation is dedicated to extremely arid and hot climates in which large daily temperature swings occur. These conditions are thus far from the human physiological comfort (comfortable temperature, lighting and humidity), which also make it hard to grow crops. Using a climatic canopy makes it possible to cultivate plants and produce food in areas which have previously not been used for farming, thus making self- sufficient settlements possible.

The installation creates thermal gradients which can be used to produce energy, e.g. by the controlled generation of a katabatic wind to drive air turbines and thus produce electricity. An alternative method of using this flux of cooled air to produce energy is thermal conversion, e.g. thermoelectric, using a low-boiling medium, or electro-thermal-magnetic conversion. It is also possible to produce fresh water for farming and human use, by increasing relative air humidity until the dew point is achieved in the space under the climatic canopy.

The solution invented is described with examples of its design in illustrations, whereas individual figures present the following:

Fig. 1 - situation of the installation in the terrain, in a natural canyon;

Fig. 2 - situation of the installation in the terrain, on a plateau with a cliff;

Fig. 3 - the canopy in a perspective view, in partial cross-section;

Fig. 4 - the canopy with an additional top layer, in a perspective view, in partial cross-section;

Fig. 5 - the flap opening and closing system

Fig. 6 - the layout of straight galleries;

Fig. 7 - the canopy open from the top;

Fig. 8 - a cell in the form of an air trap, sigmoid in shape; Fig. 9 - a cell in the form of an air trap, concentric in shape;

Fig. 10A, 10B, IOC - canopy layer options;

Fig. 11 - a scaffolding-type structure of a layer.

The primary element of the installation is canopy 1 divided into cells 2, suspended from ropes 3 by slings 4, which makes it possible to isolate the space under it from the surrounding atmosphere and to control the microclimate of this space.

Canopy 1 changes the thermal conditions in this space its shields (statically or dynamically). Canopy 1 constitutes (i) effective thermal insulation in a way ensuring that the masses of cold air are kept under it, (ii) causes the relative humidity of air held under it to grow, (iii) influences air movements inside by cutting the space off from external air movements, i.e. the wind field in the atmosphere above the canopy, and forms a local circulation system making use of thermal convection, (iv) changes radiation conditions (from ultraviolet to far infrared) primarily by reducing the amount of solar energy reaching the ground. The purpose of canopy 1 is to cool the area under it and make it more humid by reflecting as much solar radiation as possible (coming directly from the sun, or radiation dispersed by the atmosphere and coming from the entire sky) and to let energy emitted by the ground in the infrared range out.

From the point of view of its mechanical integrity, canopy 1 stretched above the ground can be held up by a system of ropes supported by pillars or anchored directly in the ground, depending on the relief of the area. An alternative option is to build the canopy 1 as a self- supporting structure by filling cells 2 with a lighter-than-air gas, preferably non-flammable, e.g. a mixture of hydrogen and nitrogen. This solution, however, requires installing a permanent and tight system of covers: both under and above the cells. If canopy 1 shields buildings, it may be stretched higher up above the ground, and if it shields valleys or uneven terrain, the distance between the ground and canopy 1 may be varied, and long in places. A favourable location for the entire installation is the surface of a plateau. The upper surface of canopy 1 may be strengthened by a lightweight skeleton (scaffolding) e.g. of composite materials, which maintains the shape of cells regardless of wind pressure. A skeleton of a similar structure can also be used to maintain the shape of lower parts of cells 2.

Canopy 1 is a flexible, multilayer structure, divided into cells 2, vertical or sloping northwards (if the installation is located in the northern hemisphere) at an angle of approx. 45°. It is recommended that canopy 1 should have a honeycomb structure parallel to the ground surface (figure 3 - fig. 5). Cells 2 are then shaped as adjacent hexagonal columns or have the structure of galleries with parallel flat ribbons constituting cell walls (figure 6).

Cells 2 have side walls 5 and are closed from the bottom or from the top, or from both the bottom and the top with lids 6, which are optically selective just like the wall surface 5. If the atmosphere above canopy 1 is warmer than the air under canopy 1, thermal/density stratification occurs in cells 2, as a result of which the entire canopy 1 becomes a thermal insulator preventing heat from penetrating from the atmosphere to below this canopy 1. An alternative solution is to build cells 2 as open from the top and the bottom with air movement inside them blocked by shaping them like air traps 22 (a partition-less air lock) of sigmoid (figure 8) or concentric shape (figure 9). This air trap system 22 lets all FIR radiation through, acting as an empty wave guide or light pipe. This solution produces a thermal density stratification and the air is immobilised, allowing this layer of air to be used as thermal insulation and preventing wind from penetrating under canopy 1. Optionally, cells 2 in the form of air locks can additionally be sealed from underneath with covers. It is necessary to install a pipe evacuating atmospheric waste and sediment which would degrade the optical properties of canopy 1.

The total longitudinal cross-section of the cell in the form of an air trap 22 is much taller than if a straight cell were used, which results in a smaller effective aperture (clear opening) of the layer surface, i.e. restricted transparency to long wave radiation. In order to avoid these limitations, when using air traps 22, bottom inlets 23 of cells 2 should be shaped as complex paraboloids or Winston cones. This optical structure has a higher acceptance angle of the incident radiation then a straight cylinder has, and so the quantity of diffused, isotropic radiation emitted by the ground that is accepted increases.

If cells of canopy 1 are long enough, it is possible to eliminate covers 6 altogether (fig 7). This method also eliminates the accumulation of rain or snow and atmospheric sediment on canopy 1. Neither is there a problem with transparency to FIR or the photodegradation of covers 6 which are sensitive to UV-VIS.

Walls 5 of cells 2 are made of flexible laminates reinforced with fabrics, and their surface is optically selective. It acts as a mirror for far infrared and also for radiation from the UV-VIS range and the NIR, or is covered with a layer retroreflective only to UV-VIS and NIR, and also reflective to FIR. In a special case, if the lower cover 6b sensitive to UV radiation is used (e.g. made of HDPE or MDPE), the upper part of walls 5 of cell 2 must be covered with a material containing a UV stabiliser which converts the UV photon energy into heat, which should then be diffused by convection and evacuated above canopy 1.

Depending on the design version of the invention, every cell 2 or sector of cells 2 can be fitted with one or two covers 6: upper cover 6a and lower cover 6b. Covers 6 may fulfil several functions: a physical barrier segregating the space inside cells and under the surface from the surrounding atmosphere and of an optically selective layer transparent to far infrared but reflecting visible light.

If the invention is used in the option in which every cell 2 or sector of cells 2 is equipped with one cover 6, the latter can be located at the top or bottom of cell 2.

The upper cover 6a must be transparent to long-wave infra-red radiation. The cover 6a must have the optical characteristics of a cold mirror, i.e. a dichroic mirror, selective for the UV- VIS and NIR radiation while transparent to FIR. This restricts the choice of materials of which cover 6a can be made. Possible materials are organic ones like polymers or waxes, such as amorphous fluoropolymers, HDPE or MDPE, or high melting point paraffin waxes, and inorganic crystalline materials such as NaCl, ZnS or Si, or a combination of these components. This is due to the need for the cover to meet requirements concerning its mechanical strength and resistance to weather, and in particular to photodegradation as well as extreme temperature changes and humidity.

The cover material 6 may be a composite foil reinforced with a mesh of metallised glass fibre or metal, possibly pressed into a composite or metal micro-grid (lattice) coated with a reflective metallic layer, as a result of which the micro-grid does not block the FIR radiation from the ground. This foil can be made of e.g. ZnS nanograins ca. 300 nanometres in diameter or ZnS nanofibers (figure 10), can be several dozen micrometers thick and pressed (figure 10A) or bonded with amorphous fluoropolymers or paraffin waxes (figure 10B) and covered with a non-reflective moth eye microstructure with the separation, module and height of about 1 μπι, intended to dampen reflections of radiation with the wave length of 8-12 μπι, additionally protected from moisture by a layer of amorphous fluoropolymer or AI2O3 up to 1 μπι thick, transmissive to long-wave infrared radiation.

In another option, cover 6 is made of a film several dozen micrometers thick, pressed together or bonded of NaCl nanograins sized about 300 nm or NaCl nanofibers (figure IOC), covered with a non-reflective moth eye microstructure with the spacing, module and height of about 1 μπι, intended to dampen reflections of radiation with the wave length of 8-12 μπι, additionally protected from moisture by a layer of amorphous fluoropolymer or AI2O3 up to 1 μπι thick, transmissive to infrared radiation.

In yet another option, cover 6 is made of a foil of foamed, amorphous tetra fluoropolymer (a microfoam or an airgel), preferably with a fractal, hierarchical pore structure, with the total material thickness not exceeding 3 μπι.

Another possible material for cover 6 is a foil of ultra-pure mono- or polycristalline silicon, up to 50 μπι thick, transparent to long-wave radiation and reflecting solar radiation, finished with a microstructure reflecting visible light, but anti-reflective to FIR.

All the above materials, if used as a thin enough layer (less than 10 μπι), are transparent to far infrared (8-12 μπι), while their high reflexivity to UV-VIS and NIR can be ensured by the appropriate combination of these components and giving them the appropriate 3D structure. A diffusive reflection of solar radiation can be ensured by dispersing elements of various refractive indices or by applying controlled micro- and nano-porosity to cover 6a. If cover 6a is at the top, the materials must meet tougher requirements, particularly due to a higher load of UV-VIS radiation. A lower-cost material not resistant to UV-VIS radiation, like a finely- foamed HDPE or MDPE can be used here, as long as it contains a UV stabiliser and the canopy is replaced every few years, which also partly eliminates the problem of dirt accumulation.

In another option, the cover is made of a sheet of material opaque to long-wave radiation, of very high absorptivity and emissivity of this radiation and high diffusive reflectivity to UV- VIS and NIR radiation, although it may be partially transmissive to this range (silicate milk glass (i); foamed glass (ii); foamed polymers resistant to photodegradation (iii); a non-woven mat or a glass textile of silicate (iv), boron/silicate (v) or boron/lithium glass (vi)).

If cover 6b is located in the lower part of the cell, its core can also be made of other materials opaque to FIR (possibly also to UV-VIS), including metals or inorganic fibres, particularly glass fibre or fibre-reinforced polymer composites. What is important for this solution are the optical properties of the surface, particularly high FIR emissivity and absorptivity coupled with high reflectivity to UV-VIS and NIR.

Hence, in the first option, optically selective cover 1 is transparent to FIR and reflects UV- VIS and NIR, in the second option it is opaque, highly absorptive and highly emissive for FIR while reflective (in a diffusive or mirror fashion) to UV-VIS and NIR.

Using two covers, upper 6a and lower 6b, improves the operation of canopy 1 as a thermal barrier separating the thermally stratified gas inside cells 2 from the space above and below canopy 1. This will prevent thermal convection and gas movements forced by the wind field from occurring in cells 2. Both the upper cover 6a and the lower cover 6b should have the optical features described for the invention built according to the option with a single cover 6.

One of the main problems with the efficiency of installation operation is dust, precipitation and atmospheric sediment settling on canopy 1, and particularly on its optical parts. For this reason, canopy 1 must be fitted with a system for removing water, snow and dust, particularly from the surface of covers 6. There are vertical channels allowing the material collecting on the surface of canopy 1 to be evacuated between individual cells 2. The ducts should be equipped with apertures which will let material through when it loads them, but will not let light through.

The upper ring of each cell can, in some design solutions, be equipped with a system of flaps 8 (figure 5) making it possible to close and seal off the inside of cell 2 including cover 6 from the atmosphere above canopy 1 if unfavourable atmospheric conditions occur (dust storms, precipitation, strong winds), and also if the temperature drops at night and could cause the ground surface below the canopy to freeze, destroying possible crops. What is important is the ability to centrally control the closing and opening of all cells 2 or their selected sectors. This can be done by the mechanical coupling of all flaps 8 which means that the change of the position of one flap 8 would force the same change of the position of all flaps 8 or a selected sector of flaps 8.

For dry climates with a cold season, canopy 1 can serve to protect the crops under it from being chilled. In the cool season, the climate control function could be reversed when necessary, i.e. the canopy 1 would act as a greenhouse. This function is best fulfilled by a solution with cells 2 designed as air traps 22, blocking air movement regardless of the thermal gradient orientation.

As a result of a temperature drop of air under canopy 1, its relative humidity will rise, causing water vapour to condense. Moisture condensed from cooled air in the form of dew drops may settle on the surface of covers 6 (if they are designed as opaque to FIR). If covers 6 are opaque to FIR, they will constitute the coolest element of the entire system, so condensation will occur mainly on their surface, and the drops formed will fall as artificial rain. Condensation may also take place in the entire space under canopy 1, near the ground, on the ground, or may form a suspended fog. To collect the water thus formed in the most effective way, the space under canopy 1 should be fitted with the appropriate equipment. Depending on local conditions, this water may be used directly under canopy 1, e.g. for irrigating crops, or may be routed down slopes and used as potable water.

There are several methods of recovering potable water out of fog (condensing fog) which will form under the layer. They are based on the hydrophobic or hydrophilic nature of the surface which water molecules of the fog come into contact with. One of them consists in capturing water molecules using special fine mesh nets made of e.g. polypropylene. It will be beneficial to install a set of such nets at the inlet into the air duct through which the entire stream of air cooled under canopy 1 passes.

Parts list

1 Canopy

2 Cells

3 Rope

4 Sling

5 Cell walls

6 Cell cover; 6a - upper, 6b -

7 Cleaning channels

8 Flaps

Abbreviations

UV - ultraviolet radiation

VIS - visible radiation

NIR - near infra-red radiation

FIR - far infra-red radiation

Claims

Patent claims

1. A geoengineering installation for obtaining renewable energy and water from atmospheric air consisting of an insulated space naturally or artificially demarcated in the terrain, particularly in a hollow on a slope, in a valley, a canyon or a plateau, separated by a canopy constituting a climate membrane from the atmosphere, with an air inlet and outlet, in which space a movement of air masses caused by their cooling occurs, while the air outlet is connected to ducts routing the cooled air into an assembly converting the mechanical energy of the moving air into other forms of useful energy, particularly electricity, characteristic in that canopy (1) is a system for the radiant cooling of air masses held between the ground and the canopy (1) and consists of an optically selective structure allowing infrared radiation emitted by the ground to escape through it into outer space, but reflecting visible, ultraviolet and near infrared solar radiation, both directly incident and scattered by the atmosphere.

2. An installation as claimed in 1 characterised by its canopy (1) divided into cells (2), depending on the design, with different cross-section geometries, preferably hexagonal (honeycomb), vertical sloping northward (N) in the northern hemisphere or southward (S) in the southward hemisphere, preferably at 45°, or galleries running W-E, while the walls of cells (2) forming part of the canopy are stretched on a mechanically strong skeleton that makes them rigid or the rigidity of canopy (1) is ensured by the pressure of a gas filling cells (2).

3. An installation as claimed in 2 characterised by walls of cells (2) forming part of the canopy (1) made of a flexible, strong polymer coated with a mirror-like layer reflecting long-wave and solar radiation, or retro-reflective to solar rays directly incident, as a result of which cells (2) function as a light pipe for infrared radiation.

4. An installation as claimed in 2 characterised by walls of cells (2) designed as mirrorlike due to a metallic layer of aluminium or silver coated with a see-through protective layer, preferably of aluminium oxide or a glassy fluoropolymer, which additionally prevents dust from settling due to the hydrophobic properties of this layer; for the retro-reflective coating, it is permissible to use a retro-reflective prismatic or spherical foil, preferably coated with a hot-mirror-type low emission coating of low absorbency.

5. An installation as claimed in 2 characterised by cells (2) sealed at the bottom with covers (6) stretched on a rigid or flexible frame, preferably vertical (in the case of skewed cells or galleries) or sloping (for vertical cells) in order to evacuate the dust and rain or snow falling on canopy (1), whereas the lower covers (6b) of cells (2) are made of an optically selective material transmissive to far infrared radiation (8-12 μπι), but reflecting (wholly or partly) solar rays from the UV-VIS and NIR ranges, both dispersed and directly incident, or from a material opaque to infrared and having the features of an absolute black body for FIR, i.e. one having high emissivity and absorbency in this spectral range.

6. An installation as claimed in 4 characterised by cells (2) additionally shielded with horizontal covers (6a), preferably forming parts of a sheet covering more than one cell, and preferably the greatest possible number of cells, made of an optically selective material transmissive to far infrared radiation (8-12 μιη), but reflecting (wholly or partly) solar rays from the UV-VIS and NIR ranges, both dispersed and directly incident.

7. An installation as claimed in 2 characterised by the column of gas in open cells (2) stabilised by an air trap (22), whereas the lower inlet (23) of cells should be shaped as a Winston cone or a complex paraboloid with walls that act as mirrors to FIR radiation as well.

8. An installation as claimed in 2 characterised by cells (2) fitted with flaps (8) for adjusting the amount of long-wave radiation passing through the layer and protecting them from unfavourable weather, which flaps (8) are closed individually or mechanically interconnected.

9. An installation as claimed in 4, 5 and 6 characterised by the material of cover (6) being optically selective, of a film several μπι thick, pressed together or joined of ZnS nanograins sized approximately 300 nm or ZnS nanofibers, coated with a non- reflective moth eye microstructure with the separation, module and height of about 1 μπι, intended to dampen reflections of radiation with the wave length of 8-12 μπι, additionally protected from moisture by a layer of amorphous fluoropolymer or AI2O3 up to 1 μπι thick, transmissive to infrared radiation.

10. An installation as claimed in 4, 5 and 6 characterised by the material of covers (6) consisting in a film several μπι thick, pressed together or bonded with an amorphous fluoropolymer of NaCl nanograins sized about 300 nm or NaCl nanofibers, coated with a non-reflective moth eye microstructure with the separation, module and height of about 1 μπι, intended to dampen reflections of radiation with the wave length of 8- 12 μπι, additionally protected from the effects of moisture by a layer of amorphous fluoropolymer or AI2O3 up to 1 μπι thick, transmissive to infrared radiation.

11. An installation as claimed in 4, 5 and 6 characterised by cover (6) material consisting in a foil of foamed tetra fluoropolymer (a microfoam or an airgel), preferably of a fractal, hierarchical pore structure, with the total material thickness no greater than 3 μπι.

12. An installation as claimed in 4, 5 and 6 characterised by cover (6) material consisting a foil of ultrapure mono- or polycristalline silicon, up to 50 μπι thick, transparent to long-wave radiation and reflecting solar radiation, coated with a microstructure reflecting visible light, but anti-reflective to FIR.

13. An installation as claimed in 4, 5 and 6 characterised by cover (6) made of a sheet of material opaque to long-wave radiation, of very high absorptivity and emissivity of this radiation and a high diffusive reflexivity to UV-VIS and NIR radiation, although it may be partially transmissive to this range (silicate milk glass (i); foamed glass (ii); foamed polymers resistant to photodegradation (iii); non-woven mat or a glass fabric of silicate (iv), boron/silicate (v) or boron/lithium glass (vi)).

14. An installation as claimed in 4, 5 and 6 characterised by the cover (6) material consisting in a sheet of finely foamed (less than 1 μπι) high or medium density polyethylene (HDPE or MDPE) stabilised against UV radiation, transmissive to longwave radiation and reflective to solar radiation, preferably with a surface microstructure reflecting visible radiation but anti-reflective to FIR.