AU2017100315A4 - A multi-layered structural material for conversion of solar radiation to kinetic energy of fluids - Google Patents

Abstract

A multi-layered structure used for conversion of solar radiation into kinetic energy of a fluid located between the layers of the multi-layered structure in order to utilise the kinetic energy for generation of electricity using a turbine or a similar device. Each section of this multi-layered structure comprises a 5 layer of material that is fully or partially transparent to the solar radiation, and a layer of material that absorbs the solar radiation in order to convert it to kinetic energy of the fluid beneath and above the layer of this material and that is located at some distance from the layer of material that is fully or partially transparent to the solar radiation, and a volume of a fluid situated between the layers of these two materials, and a volume of a fluid situated between the layer of material that absorbs the solar 10 radiation and the ground material. Figure 1. A schematic diagram of a section of a solar-wind farm that is located over a slopped ground. iA

Description

2017100315 19 Mar 2017 - 1 -

A MULTI-LAYERED STRUCTURAL MATERIAL FOR CONVERSION OF SOLAR RADIATION TO KINETIC ENERGY OF FLUIDS

Background of the Invention [0001] This invention relates to the development of a multi-layered structural material that allows for conversion of solar radiation to kinetic energy of a fluid and to subsequent generation of electricity in a facility that is known as solar-wind farm.

Description of the Prior Art [0002] The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that the prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

[0003] A solar wind farm, which in some reference sources is referred as a solar updraft tower, works on the basic principle that hot air rises. The classical design of a solar updraft tower system is described by Schlaich et al. (2009), Figure 1. The solar updraft tower has three essential elements - a large solar air collector at the base, a chimney (tower), and a wind turbine. The solar air collector is formed by a roof that is circular, transparent or translucent and open at the periphery and the natural ground below the roof. In the middle of the roof there is a vertical tower with large air inlets at its base. The joint between the roof and the tower base is airtight. The solar radiation heats the natural ground below the roof, which heats the air between the ground and the roof. As hot air is less dense than cold air it begins to rise towards the chimney. Suction from the tower then draws in more hot air from the collector, and cold air comes in from the outer perimeter, forming a continuous air flow from the outside of the collector to the chimney. The energy of the flow can be harnessed by the use of a turbine at the chimney base, which runs a generator that outputs electricity. The energy stored in the ground allows the tower to work overnight, although at a decreased level. Thermal storage (e g. concrete slabs or water tubes/channels) can be used to improve overnight performance by accumulating heat during the day and releasing it at night; however, at the cost of reduced maximum output during the day, Kreetz (1997). 2017100315 19 Mar 2017 -2- [0004] The fundamental dependencies and influence of the essential parameters on power output of a solar tower are presented in a simplified form by Schlaich et al. (2009):

The power output P [W] of the solar updraft tower system can be calculated as the solar input Qsoiar [W] multiplied by the respective efficiencies of the collector, the tower and the turbine(s): P = Qsoiar VoollV,merVturb,ne Equation (1), where the solar energy input Qsolar into the system can be written as the product of the global horizontal radiation Gh [Wm'2] and the collector area Acoll [m2]:

Qsoiar = GhAcoii Equation (2),

and the tower efficiency is given in Equation (3), Schlaich (1995): sH H.o.er = Equation (3). CPTo

Here g is the gravitational acceleration, 9.81 [ms'2], H is height of the chimney (tower) [m], c is the specific heat at constant pressure [Jkg^K'1], and T is the temperature [K] at ground level.

Thus, the power output P is fundamentally dependent on global horizontal radiation, the area of the collector and the height of the chimney (tower).

[0005] Naturally, the global horizontal radiation Gh depends on the solar radiation flux, Pol [Wm'2], the angle of incidence and the solar absorptance properties of the heated material, a.

[0006] The method of generating electricity by using the classical design of the solar wind farms (solar updraft tower systems) is well established. An early description of a solar chimney power plant has been published by Gunther (1931). Between 1978 and 1981 patents on a solar chimney electric power generation have been granted in Australia, Canada, Israel and the USA (AU patent 499934B “Apparatus for converting Solar to Electrical Energy”, CA patent 1023564 “Utilization of Solar Energy”, IL patent 50721 “System and Apparatus for Converting Solar Heat to Electrical Energy” and US patent 4275309 “System for converting solar heat to electrical energy”). A number of research manuscripts on this topic have been published and several test facilities have been built around the world.

[0007] Stamatov and de St. Amatus (2009) proposed encapsulating closed landfills with the roof of the solar updraft tower power plant. Since the solar updraft towers are able to impel 2017100315 19 Mar 2017 -3 - large gas volumes from lower to upper levels of the atmosphere, they can be used to reduce the environmental impact of uncontrolled emissions of harmful landfill gases to the neighbouring (often densely populated) areas. The authors modelled the case of a roof made from a non-transparent material. In this case, the ground retains its initial temperature and the air between the ground and the roof is heated by the roof. The modelling results shows that the velocity of the flow through the chimney increases considerably if there is an additional ground heating source as from active bio-waste decomposition.

[0008] An important factor that hindrances the practical implementation of the classical design of the solar updraft towers is the overwhelming capital cost of the chimney (tower) and the roof. The calculations of Schlaich et al. (2009) show that the capital cost of the chimney (tower) of a 200 MW solar updraft tower power plant can reach €170 millions and the capital cost of the collector can reach €261 millions.

[0009] To overcome the high capital cost, the chimney (tower) can be placed on a hill or mountain slope, US patent 7026723 “Air filtering chimney to clean pollution from a city and generate electric power”. Here, the inventor proposed a solar chimney assembly including a cylindrically shaped chimney that is build using a mountain as support. The chimney can be built from concrete or, in alternative embodiments, of plastic or polymeric materials, e g., kevlar, polyvinylchloride (PVC), polycarbonate, or similar materials. The use of these materials is expected to increase the temperature and the speed of the air, which the chimney receives air from a solar heated collector that has a glass roof and that is located at the base of the chimney. The created updraft flow of air drives a turbine or a set of turbines. In alternative embodiments, the roof can be made from plastic or polymeric materials, e.g., kevlar, PVC or the like.

[0010] US patent 8823197 “Diagonal solar chimney” describes a structure built as a long diagonal circular or oval chimney on a slope of a mountain, which can permanently generate airflow for producing electricity. In the invention’s primary embodiment a diagonal chimney is laid on the side of sloping terrain. Laying the chimney diagonally on existing terrain reduces the engineering cost of supporting an extremely high altitude vertical chimney. The chimney’s bottom end is substantially lower in elevation than its top end. Limited and gentle bends in the chimney may be built as needed to reduce engineering costs on unfavourable terrain. In use, air or other gases are continually drawn into the chimney’s bottom end. The chimney's top end has an opening to release air. In this embodiment, the chimney’s roof 2017100315 19 Mar 2017 -4- absorbs solar radiation. This heats the incoming air. The warmed air rises up the chimney. In this embodiment, a wind turbine is turned by the chimney's draft to produce electricity.

[0011] The air pathways may be of solid construction, they may be air-inflated tubes, they may be tent-like fabric tubes supported at regular lengths by poles, towers, girders or other structures, or they may be some combination of these construction methods. In one embodiment of the US patent 8823197, a solar chimney roof has multiple layers to deal with multiple engineering needs. The outermost layer blocks ultraviolet rays and protects the inner layers from water leakage, pounding from hail, blowing branches and sparks from wildfires. Beneath the outermost layer, a positive pressure containment layer girded by cables holds the chimney roof in place against positive pressure. Beneath the pressure containment layer an insulation layer reduces heat losses. Beneath the insulation layer a fairing layer held in place by guide struts reduces air turbulence in the air mass moving up the chimney at a fairly high velocity.

[0012] In one embodiment of the US patent 8823197, the chimney gathers ground-effect preheated air from a wide circumference around the bottom of the tube.

[0013] In one embodiment of the US patent 8823197, a trench in the ground with a black cover through which inlet holes have been made at intervals, sucks down pre-warmed open desert surface air. In this embodiment the area directly on either side of the trench has been sprayed with tar to further heat the air near the inlet holes, and to heat the soil or sand around the trench so that the heated soil or sand in turn eventually heats the air inside the trench.

[0014] In one embodiment of the US patent 8823197, a trench used to contain a stream of relatively unheated air has a substantially circular bottom half. This, plus a substantially circular top half cover maximizes the trench’s cross-section for best airflow for its diameter. The trench’s top half is a cover comprised of multiple air bladders, designed to be very long in the direction of air flow, which are kept inflated by one or more air pumps through one or more inflation tubes. The tubes form substantially a circular array of bulges around the trench/cover’s hollow centre that is used for shipping warm or hot air. A low positive pressure within the central part of the trench created by an air current pushing fan will also help to keep the cover inflated against various outside pressures. The outside of the tube has flaps or other connectors so as to connect the tube to anchors in the ground. In the event of high winds, in one embodiment the air pumps deflate the bladder and a fan draws all air out 2017100315 19 Mar 2017 -5- of the trench’s interior, and so the cover is held by vacuum flat against the trench’s bottom. In one embodiment a section of an air tube has similar inflatable bladders around its entire circumference, top and bottom. In one embodiment, strong, resilient rings are installed around the air tube’s outside to keep the air tube from bending shut in high winds. In other embodiment long rods extending lengthwise in an air stream enclosing tube holds fabric or plastic fairing surface fairly taut. The fairing may bulge in or out between the rods, based on whether the tube has negative or positive air pressure compared to air outside the fairing, but in the lengthwise direction the fairing has no bulges.

[0015] In one embodiment of the US patent 8823197, numerous small air-gathering trenches are an economical way to supply a single, wide chimney with a stream of perpetual warm air. The sub-goal of building small trenches is to inexpensively transport somewhat moist, slightly warm air from distant spots, and to heat this air as the trench air approaches the next air heating stage. A long covering is attached to the tops of the walls, enclosing the trench. The trench covering may vary. A simple black fabric covering will transmit a small amount of heat into the enclosed air on sunny days. A clear or translucent single layer plastic or glass covering will transmit the sun's heat to the trench’s bottom. In one embodiment a heatabsorbing trench is coated with a layer of a black or dark material on its bottom, for example, a spray of tar. Alternatively, a layer of tarpaper supported above the trench’s bottom by an insulating layer will transfer a large percent of the absorbed solar heat into air heat, putting little of the heat into the ground below.

[0016] In one embodiment of the US patent 8823197, thin heat-conducting spikes are pounded into the bottoms of the trenches before they are covered, and radiator fins are then attached to the top ends of the spikes. In operation these spikes slowly transmit captured solar heat deep into the ground during the day, then draw the banked heat up at night for preheating air inside the trenches. The radiator fins are slanted parallel to the trench's direction, to allow roughly optimal airflow through the trench.

[0017] In one embodiment of the US patent 8823197, a progression of single glazed, then double-glazed, trench covers are used to cover a trench as the trench approaches a larger air collecting tube. The flow of air in the trench becomes hotter, and so more and more insulation becomes cost-effective to continue heating the air. In one embodiment the trench then progresses to a triple glazed cover. 2017100315 19 Mar 2017 -6-

Summary of the Present Invention [0018] In one broad form, the present invention seeks to provide a structural multi-layered material that can be utilised for conversion of solar radiation to kinetic energy of fluids in a facility for multistage conversion of solar radiation to electricity.

[0019] The facility for multistage conversion of solar radiation to electricity is referred here as a solar-wind farm. In other reference sources this sort of facilities for conversion of solar radiation to electricity are commonly referred as solar updraft towers. Hence, the solar-wind farm can be considered as an innovative energy efficient and a cost effective modification of the solar updraft tower’s design.

[0020] Typically the multistage conversion of solar radiation to electricity in a solar-wind farm includes the following stages: a) the solar radiation heats a material that is exposed to the radiation; b) then, the heat of the material is converted to kinetic energy of the surrounding fluid; and, c) the kinetic energy of the fluid is converted to electricity by using a turbine or alike.

[0021] Typically the material that is heated by the solar radiation is made in a form of a sheet that is relatively thin in respect to its length and width.

[0022] Typically the material of the sheet is selected to have high solar absorptance. This can be, for example, a sheet of metal tinted in black or other suitable colour, a sheet of carbon fibre material or other natural or synthetic material.

[0023] Typically one or several jointed sheets of the material that is heated by the sun are bent to form a tunnel like structure, which is anchored or attached by any other means to the ground or freely laying on the ground. The sheet(s) forming the tunnel may support their own weight, or they may need to lie on a frame of any design that will bear the weight of the sheet(s) and its own weight.

[0024] Typically the shape of the cross-section of the tunnel may vary from being circular to oval, or to semi-circular, or to the form of an arc curved to any shape, or to any other geometrical shape. 2017100315 19 Mar 2017 -7- [0025] Typically the tunnel’s front and rear ends are open to the surrounding environment, either directly or indirectly through other adjoining structures. For example, one or both of the ends of the tunnel can be connected to vertically standing hollow tube(s).

[0026] The function of the tunnel that is made from the thin sheet(s) of material that is heated by the solar radiation is to heat the surrounding fluid, thus, to convert the solar energy into kinetic energy of the surrounding fluid.

[0027] Another function of the inner surface of the tunnel is to form walls to confine the fluid and to direct the motion of the fluid’s flow.

[0028] Typically the outer surface of the shell borders the surrounding environment.

[0029] Typically the sheet(s) of material that is heated by the solar radiation heats the fluid that is located bellow the bottom surface of the sheet(s) and the fluid that is located above the top surface of the sheet(s).

[0030] Typically thin sheet(s) made from materials having low thermal inertia will facilitate faster heating of the fluid located bellow the bottom surface of the sheet(s).

[0031] Typically the outer surface of the tunnel that is used to convert the solar energy into kinetic energy of the surrounding fluid, with the exception of the front and the rear ends, is surrounded by an additional outer shell of material.

[0032] Typically the material of the outer shell is transparent, fully or partially, to the solar light. For example, the material of the outer shell may be transparent to this part of the spectrum of the solar light that may best heat the material of the inner tunnel, and to be nontransparent to the spectrum of the light emitted by the fluid located between the inner tunnel and the outer shell.

[0033] Typically the outer shell’s front and rear ends are open to the surrounding environment, either directly or indirectly through other adjoining structures. For example, one or both of the ends of the outer shell can be connected to vertically standing hollow tube(s).

[0034] Typically, there is a distance between the inner tunnel and the outer shell that allows for free motion of the fluid between the two surfaces. 2017100315 19 Mar 2017 -8- [0035] Typically the outer shell is anchored or attached by any other means to the ground or freely laying on the ground, or it is mounted to the structure of the inner tunnel. The material of the outer shell may support its own weight, or it may need to he on a frame of any design that will bear the weight of the outer shell and its own weight.

[0036] The function of the inner surface of the outer shell is to form walls to confine the fluid between the inner tunnel and the outer shell and to direct the motion of the fluid’s flow.

[0037] Thus, the solar-wind farm typically contains two streams of flow, one stream moving beneath the inner walls of the tunnel and the other stream moving between the outer walls of the tunnel and the inner walls of the shell.

[0038] Thus, in a solar-wind farm of the type proposed in this invention: a) each section of the material that forms a layer that absorbs the solar radiation in order to convert it to kinetic energy of the flow beneath and above the layer of this material, and b) the section of the material that forms a layer that is fully or partially transparent to the solar radiation and that is located at some distance from the layer that absorbs the solar radiation, and c) the volume of the fluid situated between the layers of these two materials and the volume of the fluid situated between the layer of material that absorbs the solar radiation and the ground material, form an integrated unit of multi-layered structural material assembled with the purposes to: d) convert the solar radiation to the kinetic energy of the flow of the fluid that surrounds the layer of material that absorbs the solar radiation, and e) guide the motion of the flow toward the desired direction.

[0039] In one embodiment a solar-wind farm may comprise of a single section of the multilayered structural material described in [0038], [0040] In one embodiment a solar-wind farm may comprise of several sections of the multilayered structural material described in [0038] that are joined together in a line.

[0041] Typically sections of the solar-wind farm are laid on the side of sloping terrain to reduce the capital and maintenance cost related to the erection of a high vertical chimney. In 2017100315 19 Mar 2017 -9- this case the bottom end of the inner tunnel and that of the outer shell are lower in elevation than their top ends.

[0042] Typically the kinetic energy of the fluid’s stream(s) is converted to electricity by suitably located turbines.

[0043] A number of further features will now be described.

[0044] In one embodiment a solar-wind farm may comprise of several sections of the multilayered structural material described in [0038] that are oriented radially toward a common centre and that are joined there in a form that may remotely resemble a starfish.

[0045] In one embodiment the surface of the inner tunnel does not have perforations or openings of any other sort to the volume of the outer shell and the two streams of moving fluid are fully separated by the surface of the inner tunnel.

[0046] In one embodiment the two streams of moving fluid are interconnected because the surface of the tunnel has perforations or openings of any other sort or it is not fully closed. This may occur, for example, if the material of the sheet that forms the inner tunnel is made from some sort of mesh or other permeable material.

[0047] In one embodiment the sheet(s) that are heated by the solar radiation do not form a closed surface, for example a tunnel, and its predominant function is to convert the solar radiation in kinetic energy of the flow. In this case the outer shell is used to guide the motion of the fluid beneath it toward the desired direction.

[0048] In one embodiment sections of the multi-layered structural material described in [0038] can form the roof of the solar air collector of the classical type described by Schlaich et al. (2009).

[0049] The gradient of the slope on which a solar-wind farm is mounted may vary. In one embodiment sections of the multi-layered structural material described in [0038] can be mounted on the outer walls and roofs of buildings, including mounting on the vertical walls of the buildings. In this case, the solar-wind farm will have the function of: a) impelling volumes of ground level polluted air to upper levels of the atmosphere where they will be diluted to safer levels by the surrounding atmosphere; 2017100315 19 Mar 2017 - 10- b) cooling the outer walls and roofs of the buildings with streams of relatively cool atmospheric air; and, c) generating electricity.

[0050] In one embodiment section(s) of the solar-wind farm can encapsulate parts of the roofs the buildings or the entire roofs of the buildings. In this case, the solar-wind farm will have the function of: a) cooling the roofs of the buildings with streams of relatively cool atmospheric air; and, b) generating electricity by suitably located turbines that capture the motion of the solar heated air.

[0051] In one embodiment section(s) of the solar-wind farm can be laid on a horizontal terrain. In this case, the sides of the section(s) of the solar-wind farm can progressively rise from the inlet of the section(s) to the outlet of the section(s) to the surrounding environment.

[0052] In one embodiment the solar-wind farm can encapsulate closed landfills, other objects that emit smelly or other harmful gases, or ponds of waste water as, for example, in sewage treatment plants. In this case the solar-wind farm will: a) impel volumes of the harmful landfill gases to upper levels of the atmosphere where they will be diluted to safer levels by the surrounding atmosphere; b) reduce the environmental impact of uncontrolled emissions of harmful gases to the neighbouring areas; and, c) generate electricity.

[0053] In one embodiment the electricity generation by a solar-wind farm can be facilitated by the presence of heat from the ground. The source of this heat can be, for example: a) active bio-waste decomposition; b) release of heat, which has been accumulated in the ground during day time, during night time or during cloudy and rainy weather periods. In this case, the heat can be stored directly in the ground’s matter, or in blocks or pieces of solid matter, or in containers full with liquids; c) other external sources of heat, for example, hot water pipes or channels. 2017100315 19 Mar 2017 - 11 - [0054] In one embodiment the surfaces of the solar-wind farm can be used for collection of rain water and for collection of that part of the atmospheric water that condenses on the surfaces of the solar-wind farm.

[0055] In one embodiment the solar-wind farm can encapsulate former mining sites and facilitate the rehabilitation of these sites by providing shade and water to the vegetation that is planted under and around the solar-wind farm.

[0056] In one embodiment the surrounding environment is air and the solar-wind farm operates by using this air as a working fluid.

[0057] In one embodiment the surrounding environment is water or other liquid. In this case the solar absorbing material and the material that forms the outer shell are submerged into the liquid. The solar induced convection force drives the flow in vertical direction, allowing using the facility as a pump.

Brief Description of the Drawings [0058] An example of the present invention will now be described with reference to the accompanying drawings, in which: - [0059] Figure 1 is a schematic diagram of a section of a solar-wind farm that is located over a slopped ground; [0060] Figures 2A-D are examples of the basic configuration of the cross-section A-A of the inner tunnel and the outer shell of a solar-wind farm; [0061] Figures 2E-F are examples of the basic configuration of the cross-section A-A of the inner tunnel and the outer shell of a solar-wind farm with the addition of heat storage containers.

[0062] Figures 3A and 3B are schematic diagrams of sections of a solar-wind farm that are oriented linearly, and radially toward a common centre; [0063] Figures 4A and 4B are schematic diagrams of sections of a solar-wind farm that are mounted on the walls and the roofs of buildings; [0064] Figure 5A is an example of a vector map of the flow of a fluid moving inside an inclined section of a solar-wind farm; [0065] Figure 5B is an example of a contour map of the temperature distribution of the flow of a fluid moving inside an inclined section of a solar-wind farm. 2017100315 19 Mar 2017 - 12-

Detailed Description of the Preferred Embodiments [0066] An example of the method for converting solar radiation to kinetic energy of air flow and to subsequent generation of electricity in a solar-wind farm will now be described with reference to Figures 1-6.

[0067] In this example a section of a solar-wind farm 100 is mounted on an inclined solid ground 110. The angle of inclination is β. A-A is a cross-section of a section of the solar-wind farm 100. The section of the solar-wind farm includes a layer of high solar absorptance material 120 that is exposed to the solar radiation 130. Layer 120 is surrounded by volumes(s) of fluid 140 limited by the surface of the ground 111, openings to the surrounding environment 150, which include an inlet 160 and an outlet 170, and a layer of a material 180 that is at least partially transparent to the solar radiation 130. In this example the layers of materials 120 and 180 are parallel in longitude direction to the surface of the ground 111, and the inlet 160 is located in a lower position than the outlet 170. The layer of high solar absorptance material 120 converts the solar radiation 130 to the kinetic energy of the flow bellow and above the top and the bottom surfaces of the layer 120, forming a top stream of fluid 141 and a bottom stream of fluid 142. In use, a turbine, which is mounted somewhere along the sections of the solar-wind farm 100 is driven by the energy of the streams 141 and 142. In one embodiment, the horizontal width of the inlet 160 can differs from the horizontal width of the outlet 170.

[0068] The cross-sections A-A 200 of the layers of materials 120 and 180 may resemble different shapes. In the examples given in Figures 2A-D the layers of the materials 120 and 180 form, together with the surface of the ground 111, elongated tunnel-like shapes 221 and 281, respectively.

[0069] The main functions of the inner tunnel 221 are to convert the solar heat to kinetic energy of the flow and to guide the flow in the desired direction. The main function of the tunnel 281 that forms the outer shell of the solar farm is to guide the flow in the desired direction. In one embodiment, the outer shell 281 can cover one inner tunnel 221, in another embodiment the outer shell 281 can cover more than one inner tunnels 221.

[0070] In the example given in Figure 2A tunnels 221 and 281 form two co-centred semicylinders of different diameters that are jointed to the ground 210 at separate points. 2017100315 19 Mar 2017 -13 - [0071] In the example given in Figure 2B tunnels 221 and 281 form two co-centred tunnels, one shaped as an elongated arc (221) and the other shaped as a semi-cylinder (281). The tunnels 221 and 281 that are jointed to the ground 210 at the same points.

[0072] In the examples given in Figure 2A and 2B the tunnel 221 fully separates the volumes of fluids bellow and above its top and bottom surfaces.

[0073] In the examples given in Figure 2C and 2D the tunnel 221 partially separates the volumes of fluids bellow and above its top and bottom surfaces. In the first case (Figure 2C), there is a gap 222 between the ground 210 and the inner tunnel 221. In the second case (Figure 2C), the inner tunnel 221 is made of a permeable to the air mesh or fabric. In all cases the material of the outer shell 281 is not intended to be permeable to the fluid located bellow its inner surface.

[0074] In the examples given in Figure 2E and 2F there are heat storage containers 230 laying on the ground 210. Containers 230 can be entirely covered by the inner tunnel 221, or one part of containers 230 can be covered by the inner tunnel 221 and the rest of containers 230 can be covered by the outer shell 281.

[0075] In the example given in Figure 3A several sections 300 of the solar-wind farm are assembled on an inclined ground in form of a line with a turbine 310 mounted somewhere along the sections of the solar-wind farm 300.

[0076] In the example given in Figure 3B several sections 300 of the solar-wind farm are assembled radially in form of a starfish with a turbine 310 mounted near a common outlet 311. The outlet 311 can be located, for example, on the top of a hill to benefit from the natural inclination of the ground. In this example, the width of the inlet 301 exceeds the width of the outlet 302 of the sections 300.

[0077] In the example given in Figure 3C the sections 300 of the solar-wind farm are assembled radially, in form of a starfish, over a pond of waste water 320 with a turbine 310 mounted near the common outlet 311. In this example, the width of the inlet 301 exceeds the width of the outlet 302 of the sections 300.

[0078] In the example given in Figure 3C the radial inner tunnels 303 of the sections 300 have a common outer shell 304. In one embodiment the width of the radial inner tunnels 303 2017100315 19 Mar 2017 - 14- of the sections 300 can be extended in a way that the walls of the inner tunnels 303 can be joined and the joined inner tunnels 303 can have a common outer shell 304.

[0079] In the example given in Figure 4A the sections solar-wind farm 400 are mounted on a vertical wall of a building 410. A turbine 420, which is mounted somewhere along the sections of the solar-wind farm 400 is driven by the kinetic energy of the air. The solar-wind farm 400 can have different size and interior and exterior designs depending on the architectural structure and the aesthetics of the buildings. In use, the flow inside the vertical solar-wind farm 400 cools the building and generates electricity.

[0080] In the example given in Figure 4B the sections solar-wind farm 400 are mounted on an inclined roof 430 of a building. The shape of the section of the solar-wind farm 400 can resemble the shape of the roof 430, thus maximising the area exposed to the sun’s radiation and the energy output. One or more turbines 420 can be mounted, for example, near the highest point of the sections of the solar-wind farm 400 to convert the kinetic energy of the air to electricity. In use, the flow inside the solar-wind farm 400 cools the building and generates electricity. In one embodiment there are heat storage elements 440 installed to store heat during day time and to release it during night time, thus levelling the energy output throughout the day and night cycle.

[0081] A numerical simulation shows the presence of two streams of hot air, that are confined between the ground 500 and the inner tunnel 511 and the outer shell 512 of a solar-wind farm 510 (Figures 5 A and 5B). The direction of the streams is from the lower to the upper end of the solar-wind farm 510. In this numerical simulation, the inner tunnel 511 is heated by a constant flux of solar radiation. Figure 5A shows a vector map of the flow of a fluid moving inside an inclined section of the solar-wind farm 510. The arrows indicate the magnitude and the direction of the velocity of the flow. The contour temperature map in Figure 5B shows that the temperature of the flow near the surfaces of the inner tunnel 511 is higher than the ambient temperature, (in Figure 5B, darker colours indicate lower temperature and brighter colour indicates higher temperature). Together, Figures 5A and 5B demonstrate that the driving force for the motion of the fluid inside a solar-wind farm is the natural convection of the fluid, which is caused by the heating of the fluid above and beneath the surfaces of the inner tunnel 511. Figure 5B also demonstrates that a part of the heat is naturally stored in the ground 500 beneath the solar-wind farm 510. The heat stored in the 2017100315 19 Mar 2017 - 15 - ground 500 can be utilised for generation of electricity by the solar-wind farm 510 during the periods of absence of natural solar radiation. 2017100315 19 Mar 2017 - 16-

References: AU patent 499934B “Apparatus for converting Solar to Electrical Energy”. CA patent 1023564 “Utilization of Solar Energy”.

Gunther H, In hundert Jahren - Die kunftige Energieversorgung der Welt, Kosmos Gesellschaft fur Naturfreunde Geschaftsstelle: Franckh'sche Verlagshandlung, 1931. IL patent 50721 “System and Apparatus for Converting Solar Heat to Electrical Energy”.

Kreetz, H. (1997). “Theoretische Untersuchungen und Auslegung eines temporaren Wasserspeichers fur das Aufwindkraftwerk”, diploma thesis, Technical University Berlin, Berlin.

Schlaich I, Bergermann R., Schiel W., Weinrebeet G., Design of Commercial Solar Updraft Tower Systems - Utilization of Solar Induced Convective Flows for Power Generation [online], http://www.sbp.de/de/html/contact/download/The_Solar_Updraft.pdf [accessed 02.02.2009]

Schlaich, J. (1995). “The Solar Chimney”. Edition Axel Menges, Stuttgart, Germany.

Stamatov V.A, de St. Amatus A.., Utilisation of solar updraft towers for electricity generation and improvement of air quality near closed landfills in Australia, 2009 Annual Bulletin of the Australian Institute of High Energetic Materials, vol.l, pp. 1-11, ISBN 978-0-9806811-3-0. US patent 4275309 “System for converting solar heat to electrical energy”. US patent 7026723 “Air filtering chimney to clean pollution from a city and generate electric power”.

Claims (2)

1. A MULTI-LAYERED STRUCTURAL MATERIAL FOR CONVERSION OF SOLAR RADIATION TO KINETIC ENERGY OF FLUIDS THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1) A multi-layered structural material that is designed for the purpose of being used for conversion of solar radiation into kinetic energy of a fluid located between the layers of the multi-layered structural material. Each section of this multi-layered structural material comprises of: a) a layer of material that is fully or partially transparent to the solar radiation, and b) a layer of material that absorbs the solar radiation in order to convert it to kinetic energy of the fluid beneath and above the layer of this material and that is located at some distance from the layer of material that is fully or partially transparent to the solar radiation, and c) a volume of a fluid situated between the layers of these two materials, and d) a volume of a fluid situated between the layer of material that absorbs the solar radiation and the ground material.
2. 2) A method for converting solar radiation into electricity in a facility that is known as a solar-wind farm, which facility is assembled by using sections of the multi-layered structural material of the type described in 1), and which has the main purpose of utilisation of the kinetic energy of the flow for generation of electricity using a turbine or a similar device, in the following main steps: a) the solar radiation passes through a layer of material that is fully or partially transparent to the solar radiation; b) a layer of material that is capable of absorbing the solar radiation, and that is located at some distance beneath the layer described in a), absorbs, at least partially, the solar radiation that reaches it surface, and heats the surrounding fluid; c) the flow of heated fluid forms streams that are guided by the surfaces of the layers of materials described in a), b) and the ground towards a turbine or a similar device that converts the kinetic energy of the flow to electricity. d) the fluid is then expelled from the solar-wind farm facility and replaced by new volumes of fluid from the surrounding environment; e) the electricity generation continues until there is an energy input from the solar radiation, or from heat stored in the ground on which the solar-wind farm is mounted and from the heat stored in the material from which the solar-wind farm is built, or from the heat stored in special containers.