ES2557334A1 - Light sensor device with absorptivity regulation (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

A light pickup device (10, 20) comprising a plurality of transparent panels (12b, 15; 22a, 22b, 22c), configured to, in use, circulate a heat transfer fluid between at least two panels of said plurality of panels. The device (10, 20) comprises means for varying the thickness of the fluid circulating in the device, thus varying the transparency of the device. A construction module comprising the light-gathering device (10, 20). (Machine-translation by Google Translate, not legally binding)

Description

image 1

DESCRIPTION

LIGHT METER DEVICE WITH ABSORTIVITY REGULATION

5 Field of the invention

The present invention pertains to the field of light pick-up devices, such as solar thermal pick-up devices intended to collect energy from solar radiation.

10 Background of the invention

Devices for letting sunlight into a building are known while preventing overheating of the interior of the building. For example, international patent application WO1995004006A1 describes a system that has two or more glass panels that are held together by a ventilated frame.

15 The panels incorporate a doping agent or coating. This allows the transmission of visible light but the capture of solar energy outside the visible spectrum. At least one of the panels can absorb solar energy, heating the air in a chamber. This causes convection currents to vent air into or out of a building.

20 A light collector or solar thermal collector (also commonly referred to as a solar collector) is a device that tries to heat a fluid, for example water, from solar radiation. The fluids used are commonly referred to as heat transfer fluids because they are capable of absorbing energy, increasing their temperature, and transporting heat to another place. The collectors can be used so that the fluid (for example, water) serves to block infrared radiation from the sun, preventing it from reaching inside the building.

25 Normally these systems have a water circulation mechanism to release the absorbed heat. Direct absorption sensors have no absorber and heat is absorbed directly into the fluid.

Solar collectors formed by two or more sandwich panels are known. The two panels form a cavity inside which the heat transfer fluid is housed or circulated. The first panel (that is, the exterior or

30 closer to solar radiation) is generally made of glass because this material is transparent to the visible spectrum (lets in solar radiation) and opaque to infrared (does not let infrared radiation produced as a result of the heating of the fluid) producing a greenhouse effect .

Some examples of direct absorption collectors or collectors are those described by T.P. Otanicar, P.E.

35 Phelan, R.S. Prasher, G. Rosengarten, R.a. Taylor at Renew.Sust. Energ Rev. 2, 033102 (2010) or by Taylor.RA, Phelan.PE, Otanicar.TP, Walker.CA, Nguyen.M, Trimble.S, Prasher.R, in the Journal of Renewable and Sustainable Energy 3,023104 ( 2011).

For example, the company Intelliglass (http://www.intelliglass.es/Descargas/ProductosIntelliGlass.pdf) offers a

40 series of products based on double glazing with circulating water chamber. This system seeks energy management and integral air conditioning of buildings. Specifically, it is intended to let light through but not heat, avoiding internal overheating that occurs inside buildings with large glazed surfaces.

45 Some of these devices allow you to regulate the amount of light you are able to absorb. For example, US patent US6216688B1 describes a facade module composed of three parallel transparent glass plates that form two chambers. The chamber inside the building contains air and serves to insulate heat. The chamber facing the exterior is filled with a dyed or pigmented circulating fluid, so that it absorbs infrared radiation but is partially transparent to visible light. You get one

Variable absorption of light by changing the level of pigmentation or tinting of the fluid. Thus, the building is isolated from the incident radiation and also provides an efficient method of capturing solar energy through the fluid.

This same principle is used in US patent application US20130263535A1, which describes a

55 facade element for heat insulation, consisting of several parallel plates that delimit three cavities, of which the middle one has the function of thermal insulation and is filled with a gas. Through the other two cavities - the exterior and the interior (with respect to the building to which the facade belongs) circulates a fluid absorbing solar radiation. The fluid may include particles to darken or to change the color of the cavities. It is proposed that, for example, in summer, the fluid in the outer cavity be darkened with particles

60 so that the fluid absorbs infrared solar radiation and it is used, while a cold fluid is circulated inside, to cool the interior of the building. On the contrary, in winter the outside fluid is not darkened, although infrared radiation is still captured and used to heat the interior of the building. It is also proposed to evacuate the middle cavity so that the solar radiation is guided directly to the inner cavity.

65

image2

Description of the invention

The present invention provides an alternative to solar collector devices that allow regulating the

5 amount of light that they are able to absorb. Specifically, the present invention provides a light sensing device and a module or construction element incorporating said device, capable of controlling both the luminosity (or level of transparency) and the energy absorbed by them, of simple implementation.

In a first aspect of the invention, a light sensing device is provided comprising a plurality of transparent panels, configured to, in use, circulate a heat transfer fluid between at least two of those panels. The device comprises means for varying the thickness of the fluid flowing through the device, thus varying the transparency of the device.

Preferably, the at least two panels configured so that the heat transfer fluid circulates between them, are arranged parallel to each other. Alternatively, they are arranged in planes not parallel to each other.

In a possible embodiment, the device is configured so that the heat transfer fluid circulates between two panels. The means for varying the thickness of the fluid circulating between the two panels comprise one of

20 said two panels, which is mobile with respect to the other panel, both panels forming a first cavity, and fastening means to the device. The mobile panel is configured to move closer or further away from the other panel, expanding or reducing the width of the cavity, thus varying the thickness of the fluid circulating between said panels. The means for varying the thickness of the fluid may further comprise actuation means for driving the movement of the mobile panel.

In a more preferred embodiment, the device comprises two additional cavities arranged one on each side of the first cavity. Additional cavities are delimited by respective transparent panels.

In another possible embodiment, the device comprises a number N of cameras delimited by a number N + 1

30 of panels, where N is a natural number greater than or equal to 2. The means for varying the thickness of the fluid circulating through the device comprise selection means for flowing said fluid along any, some or all of the N chambers. . In a possible implementation, the width of at least two of the N cameras is different from each other, the device being configured to provide 2N different levels of transparency or solar energy absorption depending on whether, in use of the device, it is circulated a fluid along

35 none, some or all of the N cameras.

Optionally, at least one of the panels has a coating.

Optionally, the heat transfer fluid comprises nanoparticles capable of absorbing heat.

Optionally, the device further comprises ventilation means.

In another aspect of the invention, a construction module is also provided comprising the device described above. The module or building element can be both a module or element

45 facade as a module or roof element, among others. The module is preferably exterior (directly exposed to solar radiation). Alternatively, it can be used indoors, to regulate the brightness or degree of lighting of a room.

50 Brief description of the figures

To complement the description and in order to help a better understanding of the characteristics of the invention, according to an example of practical implementation thereof, a set of figures in which with character is accompanied as an integral part of the description illustrative and not limiting, what has been represented

55 following:

Figure 1 shows a device according to a possible embodiment of the invention. Figures 2A, 2B and 2C show a possible implementation of the device of Figure 1. Figures 3A, 3B and 3C illustrate how the transparency of the device is fully adjustable depending on the

60 thickness of the variable chamber. Figures 4A, 4B, 4C and 4D show an alternative embodiment of the device of the invention. Figure 5 shows an alternative implementation of the embodiment of Figures 4A-4D. Figure 6 shows a possible implementation of the device of the invention, in which a ventilation system is included.

image3

5

10

fifteen

twenty

25

30

35

40

Four. Five

fifty

55

60

65

Description of an embodiment of the invention

The light sensing device serves to regulate the amount of light radiation (preferably solar) that enters from the outside (ie "curtain" or "blind" effect), to collect energy from the radiation and reuse it for any purpose, for example , for the air conditioning of the building, both in summer and winter.

The device is capable of controlling both the light and the temperature inside the building or room, taking full advantage of the incident solar energy that reaches the device. The control of the luminosity does not imply that solar energy is wasted. On the contrary, excess solar energy is absorbed by a heat transfer fluid (in English, Heat Transfer Fluid (HTF)) to improve the energy efficiency of the building. The absorptivity of the fluid is adjusted to absorb the desired amount of solar energy (based on the combination of the needs inside the building and environmental resources outside) and transformed into thermal energy, thus converting the device of the invention into a distributed solar collector and allowing the device to regulate the lighting and thermal loads of the building.

In the context of the present invention, "fluid sheet" means the volume of fluid that is capable of flowing or circulating along a cavity delimited by two panels. In the preferred case that the two panels forming the device or part thereof are parallel to each other, the volume of fluid circulating between them can be defined through the substantially constant thickness between said two parallel panels. This substantially constant thickness is what defines in this case the "fluid sheet", there being a direct relationship between the thickness of the fluid sheet and the volume of fluid flowing through the chamber. Alternatively, the two panels that delimit the cavity may not be parallel and may not even be flat. As an example, the two panels can be flat but not parallel, defining a small angle between them, in which case a tone effect could be produced that would degrade. In another example, one of the panels or both could be corrugated instead of flat. In any of these cases, "fluid sheet" means the volume of fluid that is capable of flowing or circulating along the cavity delimited by the two panels. Figures 1 and 2A, 2B and 2C show a device according to a possible embodiment of the invention. The device 10 has at least one chamber 11a delimited by two panels or sheets 12b 15 of a transparent material. Preferably the two panels 12b 15 are of the same material, more preferably of glass. Alternatively, they can be made of different materials. The module is delimited in all its perimeter by a frame or support 18 (in the cut of these figures only the upper part in bottom of the frame or support is appreciated). Preferably the two panels 12b 15 are located substantially parallel to each other. In use, the chamber 11a is filled with a heat transfer fluid that is flowed or circulated delimited by the two panels 12b

fifteen.

The conversion of solar energy to thermal energy is carried out directly within the heat transfer fluid (HTF) or fluid with absorption capacity. The fluid may or may not have absorbent particles, for example absorbent nanoparticles. The absorbable fluid is outside the scope of the present invention. The device or module becomes opaque as the thickness of the system increases.

Returning to Figures 1 and 2A, 2B and 2C, the heat absorbing fluid enters through an access 17a and exits through an outlet duct 17b. The fluid is heated thanks to the incident solar radiation coming from outside the building.

The device 10 allows to vary the fluid sheet or amount of fluid circulating in the chamber 11a, or what is the same, allows to vary the volume of fluid or the thickness of the fluid flowing through the chamber 11a. Since transparency and absorptivity are proportional to the thickness of the fluid that has to pass through the light, the device is capable of varying the absorptivity and, therefore, the amount of solar energy that is absorbed by the fluid. That is, by varying the thickness of the fluid sheet, the transparency and, therefore, the light that passes inside, as well as the amount of energy absorbed, is regulated. And on the other hand, by varying the flow rate of the fluid, the temperature of the fluid at the outlet is also regulated, because at less speed (lower flow), the higher temperature reaches the heat transfer fluid.

The embodiment of Figures 2A-2C shows a possible way to vary the thickness of fluid (or fluid sheet) that circulates through the chamber 11a: One of the panels 15 delimiting the cavity 11a (preferably the panel closest to the interior of the building) is not completely fixed to the frame or support 18, but is a movable panel 15. This panel 15 is fixedly attached, connected or attached to an elastic fastener 16, which is placed along the entire perimeter of the panel 15 , that is, along the four sections of the panel. The elastic clamping element 16 is fixedly attached or connected to the frame 18 of the device 10. The connection between the panel 15 and the frame 18 through the clamping element 16 is airtight or airtight. In this way, by moving the panel 15 by actuating a drive device 13, the elastic clamping element 16 is stretched or shrunk / folded (depending on the position of the panel 15) and the thickness of the circulating fluid sheet varies. inside the chamber 11a. That is, through the drive device 13, the size of the chamber 11a is reduced or enlarged. Preferably the panel 15 is displaced so that it is substantially parallel to the other panel 12b that forms the cavity 11a. The drive device 13 can be mechanical, pneumatic (for example, injecting gas into the chamber 11c) or hydraulic, or in any other way that an expert can contemplate. Also, the drive device can be integrated in the frame

image4

5 18. Thus, depending on the position taken by the mobile panel 15, the transparency of the construction module will be different. In the illustrative scheme of Figures 2A-2C, the drive device 13 is formed by screws operated by an actuator (for example, a motor). Thus, a fully automatic and adjustable lighting regulation is achieved.

10 In Figures 3A, 3B and 3C a device similar to that described in Figures 1 and 2A, 2B and 2C is shown, in which automatic and adjustable lighting regulation is performed in an alternative manner to that of Figures 1 and 2A, 2B and 2C. As in Figures 2A, 2B and 2C, one of the panels 15 that delimit the cavity 11a is not completely fixed to the frame or support 18, but is a mobile panel 15. However, in this embodiment, the mobile panel 15 counts with a rigid and substantially hermetic joint 36 that slides in frame 18. Of this

15, by moving the panel 15 by actuating an actuation device 13, the joint 36 slides in the frame 18, the thickness of the fluid sheet circulating inside the chamber 11a being varied. That is, through the drive device 13, the size of the chamber 11a is reduced or enlarged. In Figure 3A the chamber 11a has a minimum width, since the drive 13 has been driven to one end. Transparency in this case is substantially total. In Figure 3B the camera 11a has a

20 intermediate width, since the drive 13 has been driven to an intermediate point. In Figure 3C the chamber 11a has a maximum width, since the drive 13 has been driven to the other end. The transparency in this case is substantially nil. In the three figures the solar lighting strikes the left part of the module (that is, the radiation strikes the left panel), while the right part of the module represents the interior of the building.

25 Thus, if it is desired to reduce the illumination inside the room and / or absorb a greater amount of radiation, the mechanism 13 is operated so that the mobile panel 15 defines a cavity 11a as wide as possible (its height and length they are fixed and are imposed by the dimensions of the panels), while if you want to increase the lighting inside the room and / or absorb a smaller amount of radiation, the

30 mechanism 13 in the opposite direction, so that the movable panel 15 approaches the other panel 12b, so that the cavity 11a is as narrow as possible, that is, the fluid sheet is narrowed (the volume is therefore reduced of fluid circulating through cavity 11a, volume that can be represented by fluid thickness). In short, the device can be implemented by any mechanism that makes it possible to move one of the panels that delimit the cavity, keeping it tight.

35 As can be seen and described, in a minimal configuration, the device 10 is formed by a single chamber 11a delimited by two panels 12b 15.

In a possible embodiment, as shown in Figures 1, 2A-2C and 3A-3C, module 10 may have at least

40 a second cavity 11b, delimited by one of the previous panels 12b (by the fixed panel) and by a third panel 12c which is fixed. The third panel 12c is also of a transparent material, preferably glass.

In a preferred embodiment, as shown in Figures 1, 2A-2C and 3A-3C, the module 10 has, in addition to the second cavity 11b, a third cavity 11c, delimited by one of the previous panels 15 (in this case, 45 by the mobile panel) and by a fourth panel 12a. Therefore, module 10 is formed by three chambers 11b 11a 11c delimited by four panels 12c 12b 15 12a (the first by panels 12c and 12b; the second by panels 12b and 15; the third by panels 15 12a), as schematized in figures 1, 2A-2C and 3A-3C. It is the interior chamber (11a) that provides variable absorptivity because the thickness of the fluid sheet that runs through it can be varied. The cavity 11b serves to produce a greenhouse effect, so that losses to the outside are reduced. In this preferred embodiment, once the device is integrated in the facade or roof of a building, the third panel 12c is one of the outer panels (with respect to panels 12b and 15) of the device, and more specifically, it is the panel that is in contact with the outside environment (for example, the street). Therefore it is the panel that receives the most direct solar radiation. The fourth panel 12a, which is also fixed, is, in this embodiment, the other of the outer panels (with respect to panels 12b and 15) of the

55 device Specifically, it is the panel that is more inside the building. This panel 12a is also made of a transparent material, preferably glass.

Figures 4A-4D show a second embodiment of the device of the invention. Specifically, in a minimal configuration, it is a device 20 with two cameras 21a 21b delimited by three panels 22a 60 22b 22c. The outer panels 22a 22c are fixed and their position defines the size (width) of the device 20. The position of the inner panel 22b is also fixed. Preferably, the inner panel 22b is substantially parallel to the two outer panels. In a preferred embodiment, its position is not symmetrical with respect to the outer panels 22a 22c of the device 20, but is closer to one of them, so that the two chambers 21a 21b delimited on one of their faces by this inner panel 22b have a thickness or width 65 different from each other. In Figures 4A-4D, for example, chamber 21b is thicker than chamber 21a. The

image5

panels 22a 22b 22c are transparent, preferably glass.

Thus, using a single heat transfer fluid that flows through any, some or all of the chambers, four levels of absorptivity (absorption of solar energy) are achieved. For this, the device 20 comprises selection means

5 to pass the fluid through any, some or all of the device cavities. More generally, if device 20 is designed to have N chambers, generally of different thickness, 2N absorption levels are achieved. In the example illustrated in Figures 4A-4D, the fluid can access the chamber 21a through an inlet 27a and out of it through an outlet conduit 27b; and the fluid can access chamber 21b through an inlet 27a ’and out of it through an outlet conduit 27b’.

10 In the case of Figures 4A-4D, N = 2. The four levels are achieved as follows: A first level, with a certain level or degree of absorption (for example, practically no absorption, when neither of the two chambers 21a 21b circulates fluid (Figure 4A); a second level, with X% of absorption, when fluid circulates through one of the chambers 21a but fluid does not circulate through the other chamber 21b (Figure 4B); a third level, with Y% absorption, when

15 the first of the chambers 21a does not circulate fluid but through the other chamber 21b fluid does circulate (Figure 4C); and a fourth level, with maximum absorption level, when fluid circulates through the two chambers 21a 21b (Figure 4D).

That is, like the device 10, the device 20 allows to vary the fluid sheet or amount of fluid flowing through it, or what is the same, allows to vary the volume of fluid flowing through the device and by

20 both the thickness of fluid circulating through the device.

Figures 4A-4D represent a minimal configuration of this second embodiment. In a possible implementation, the module designed in accordance with this second embodiment, has, as in the embodiment of Figures 1 and 2A, 2B and 2C, another camera at the left end of the module (camera 21c which

25 directly receives solar radiation and is delimited by panel 22a and another outermost panel 22d) and another chamber at the right end of the module (chamber 21d that is further into the building and is delimited by panel 22c and another panel more inside 22e). Figure 5 schematizes this preferred implementation of this embodiment.

In a possible embodiment, schematized in Figure 6, the device may have a ventilation system 19a 19b integrated to bring into contact the interior and exterior of the room and / or the extreme cavities of the device through which heat transfer fluid does not circulate. In the illustrated scheme, although the inlet / outlet ducts 17a 17b occupy part of the ventilation system, the air can circulate directly from the outside of the room into the interior thereof. The ventilation system serves to achieve effects of

35 thermal conditioning (eg heating or cooling) of the room and / or improvement of air quality. The ventilation system is applicable to any of the possible implementations of the invention and is outside the scope of the present invention.

In a possible embodiment, in any of the previous implementations, the transparent panels,

40 preferably glass, can carry a coating. Non-limiting examples of coatings are: dirt repellent coating (in English, anti-soiling), to avoid environmental dirt, hydrophobic coating to avoid drops when the fluid is not flowing, “low emission” coating to reduce radiation losses, or anti-reflective coating (in English, "anti-reflective") to achieve the highest transmissivity.

In a preferred embodiment, all panels that are in contact with the fluid have a hydrophobic coating, to prevent residual fluid dripping. And in the interior partitions, the panels can carry anti-reflective coating. And the outer surface of the module, that is, the panel on which the solar radiation directly affects, preferably has "anti-reflective" and "anti-soiling" coating, since

50 it is important that it be kept clean and that it has the greatest possible transmissivity.

Preferably, the low emission coating is applied on the inner panels of the device, and more specifically on the faces that are not in contact with the heat transfer fluid, because they are the panels with the highest temperature. In relation to the figures, the low emission coating is preferably applied

55 only on the face of panel 12b that is not in contact with the fluid. Optionally it can also be applied on the face of the panel 15 that is not in contact with the fluid.

In sum, a control system, not illustrated in the figures, intelligently manages the device, so that when there is a greater need for light, the mobile panel 15 moves to define a thickness of the chamber 11a

60 minimum, then adjust the speed of the fluid circulating through the chamber to maximize the outlet temperature.

The device and module of the invention can be used in combination with a storage system that stores the accumulated heat and distributes or reuses it according to the specific needs of each situation,

65 for example, in the form of heating.

image6

In sum, a light and thermal energy sensing device has been developed that regulates its transparency, luminosity and absorptivity without having to act on the heat transfer fluid, depending on the thickness of the fluid sheet that passes through the device and is exposed to the incident light

5 The device described has its application in windows, roofs, glazed roofs, facades in general, or in any other type of façade elements, interior of buildings, as well as in any type of buildings or infrastructures, such as houses, multifunction buildings or greenhouses, in which it is interesting to regulate both the luminosity and the thermal loads of the building.

10 Among its advantages derived from the adjustment of the thickness of the fluid that circulates through the device, the adjustment or control of the luminosity towards the interior of a building (or similar), the use of the incident solar energy and the interior comfort (for example, stand out) , ventilation).

In short, thanks to the variation of the thickness of the fluid sheet (obtained by means of a mobile panel in embodiment 1 or by several sealed chambers in embodiment 2), the proposed device offers the possibility of controlling the luminosity and interior comfort as well as the energy generated.

In this text, the word “understand” and its variants (such as “understanding”, etc.) should not be interpreted in an exclusive way, that is, they do not exclude the possibility that what is described includes other elements, steps etc.

On the other hand, the invention is not limited to the specific embodiments that have been described but also covers, for example, the variants that can be made by the average person skilled in the art (for example, in terms of the choice of materials, dimensions , components, configuration, etc.), within what is

25 emerges from the claims.

Claims (8)

image 1 1.-A light sensing device (10, 20) comprising a plurality of transparent panels (12b, 15; 22a, 22b, 22c) 5, configured to, in use, circulate a heat transfer fluid between at least two panels of said plurality of panels, characterized in that the device (10, 20) comprises means for varying the thickness of the fluid flowing through the device, thus varying the transparency of the device. The device (10, 20) of claim 1, wherein said at least two panels configured so that the heat transfer fluid circulates between them, are arranged parallel to each other. 3. The device (10, 20) of claim 1, wherein said at least two panels configured for the heat transfer fluid to circulate between them, are arranged in planes not parallel to each other. 4. The device (10) of any of claims 1 to 3, configured so that the heat transfer fluid circulates between two panels (12b, 15), wherein said means for varying the thickness of the fluid circulating between said two panels (12b , 15) comprise one (15) of said two panels (12b, 15), wherein said panel (15) is 20 mobile with respect to the other panel (12b), both panels forming a first cavity (11a), and fastening means (16, 36) to the device (10), said mobile panel (15) being configured to move closer or further away from the another panel (12b), expanding or reducing the width of said cavity (11a), thus varying the thickness of the fluid circulating between said panels. The device (10) of claim 4, wherein said means for varying the thickness of the fluid further comprise actuation means (13) for driving the movement of said mobile panel (15). 6. The device (10) of any of claims 4 or 5, comprising two additional cavities (11b, 11c) disposed one on each side of said first cavity (11a), wherein said additional cavities are delimited by respective panels transparent (12c, 12b; 15, 12a). 7. The device (20) of any one of claims 1 to 3, comprising a number N of cameras (21a 21b) delimited by a number N + 1 of panels (22a 22b 22c), where N is a larger natural number or equal to 2, wherein said means for varying the thickness of the fluid circulating through the device (20) comprises means 35 for selecting said fluid to flow along any, any or all of the N chambers. 8. The device (20) of claim 7, wherein the width of at least two of said N cameras is different from each other, the device being configured to provide 2N different levels of transparency or solar energy absorption as a function of , in use of the device, a fluid is circulated along none, 40 some or all of the N cameras. 9. The device of any of the preceding claims, wherein at least one of said panels has a coating. The device of any of the preceding claims, wherein said heat transfer fluid comprises nanoparticles capable of absorbing heat. 11. The device of any of the preceding claims, further comprising ventilation means (19a 19b). 12. A construction module comprising the device of any of the preceding claims.