TECHNOLOGICAL FIELD

The present disclosure is generally in the field of solar collectors, and more specifically the disclosure is concerned with a hybrid solar collector, configurable for handling one or more fluids simultaneously.

BACKGROUND ART

References considered to be relevant as background to the presently disclosed subject matter are listed below:

- US4,015,584

- US20150083114

- CN1760602A

Acknowledgement of the above references herein is not to be inferred as meaning that these are in any way relevant to the patentability of the presently disclosed subject matter.

BACKGROUND

US4,015,584 discloses a solar energy heat exchanger including a housing formed by parabolic shaped walls and a transparent front plate connecting the walls. A longitudinal focal tube is positioned about the focal line of the parabolic housing. The transparent front plate is faced toward the sun, permitting the rays to pass therethrough, some of which pass onto the front part of the focal tube. The inner surface of the parabolic walls reflect the rest of the sun rays which pass into the housing, and send the reflected rays to the back part of the focal tube. A plurality of flow tubes can be positioned adjacent the inner surface of the parabolic walls to receive the sun rays as well. The flow tubes can have reflective coatings around them to aid in reflecting the sun rays on to the focal tube. A top and bottom cover on the parabolic housing have holes therein which are located above and below both the focal tube and the flow tubes, permitting a pipe assembly to connect to the tubes for providing the entry and exit of a fluid into the tubes. The solar energy heat exchanger can be placed inside a dwelling, with the transparent front plate serving as the actual windowpane of a window aperture.

US20150083114 discloses a solar photo-thermal receiving device, consisting of a sealed structure and a solar photo-thermal receiver inside the sealed structure; the solar photo-thermal receiver includes a secondary absorption heat-exchange pipe and a primary absorption heat-exchange pipe; the temperature of a heat exchange medium inside the secondary absorption heat-exchange pipe is lower than that of a heat exchange medium inside the primary absorption heat-exchange pipe; the secondary absorption heat- exchange pipe receives the heat energy released by the primary absorption heat-exchange pipe and/or receives the solar heat not received by the primary absorption heat-exchange pipe; the solar photo-thermal receiving device takes the heat away via the heat-exchange medium flowing inside the pipes of the solar photo-thermal receiver. The solar photo- thermal receiving device can be applied in a through type, a Fresnel array and a tower type solar photo-thermal concentration system.

CN1760602 discloses a heat collector of solar energy is prepared as setting light focusing - reflecting component with arc shaped section on support , placing at least two metal tubes with solar energy absorbing fdm on its surface above light focusing - reflecting component , containing heat transmission media in metal tubes , making shape and size of said light focusing - reflecting component be consistence and making axial direction of metal tubes be parallel to length direction of light focusing - reflecting component.

GENERAL DESCRIPTION

The present disclosure is directed to a solar collector configured for heating at least one primary working fluid flowable in a primary tube system, and at least one secondary working fluid flowable in a secondary tube system.

Hereinafter, in the specification and claims, the terms 'working fluid' and fluid' are used interchangeably and denote and fluid, gas or liquid, suitable for being used in a thermodynamic cycle.

The present disclosure provides a solution that allows to house two heat tubes in a radiation space of a housing, each carrying a different working fluid. Thus, an external radiation that is received within the radiation space, causes heating of the heating tubes and the working fluids carried by them. These two working fluids can be used, for example, to transfer heat to/from or between two different mediums, gas and liquid, to maintain a certain range of temperatures in at least one of the mediums. For example, the primary heat tube can be used for thermal communication with the gaseous environment surrounding a desired target to maintain in a certain temperature range and the secondary heat tubes can be used for thermal communication with a liquid reservoir. During the day the heat of the radiation causes the heating of the liquid and thermal energy is stored in the liquid reservoir and during the night heat exchange from the primary heat tube to the secondary heat tubes is performed in the housing resulting in heating of the gaseous environment around the liquid reservoir to maintain a certain level of desired temperatures. This is important, for example, when you want to grow plant in that environment.

According to a first aspect of the disclosure there is a solar heat collector comprising a housing, optionally a trough-like housing, defining a radiation space extending along a longitudinal axis and comprising inside wall surfaces; a primary heat tube extending within the radiation space near a base of the trough and is intended for carrying a primary working fluid; a plurality of secondary tube supports extending along the radiation space, external to said primary heat tube and below an aperture of the housing, each configurable for supporting a secondary heat tube that is intended to carry a secondary working fluid; and wherein the primary heat tube and the secondary tube supports are integral with the housing.

The term 'aperture' of the housing refers to the gap between respective ends (along a longitudinal axis) of side walls of the trough-like housing.

According to a second aspect of the disclosure there is a solar heat collector module comprising a solar heat collector comprising a housing, optionally trough-like housing, defining a radiation space extending along a longitudinal axis and comprising inside wall surfaces; a primary heat tube extending within the radiation space near a base of the trough and is intended for carrying a primary working fluid; a plurality of secondary tube supports extending along the radiation space, external to said primary heat tube and below an aperture of the housing, each configurable for supporting a secondary heat tube that is intended to carry a secondary working fluid; and wherein the primary heat tube and the secondary tube supports are integral with the housing, and wherein the housing is configured with an end plate at its respective ends, and wherein the primary heat tube comprises a coupling arrangement, couplable with a primary heat tube of a coextending like solar heat collector module, and the secondary heat tubes comprise a coupling arrangement at each end plate, couplable with secondary heat tubes of a coextending like solar heat collector module.

According to yet an aspect of the disclosure there is a solar heat collector system comprising two or more solar heat collector modules, each comprising a solar heat collector comprising a housing, optionally a trough-like housing, defining a radiation space extending along a longitudinal axis and comprising inside wall surfaces; a primary heat tube extending within the radiation space near a base of the trough and is intended for carrying a primary working fluid; a plurality of secondary tube supports extending along the radiation space, external to said primary heat tube and below an aperture of the housing, each configurable for supporting a secondary heat tube that is intended to carry a secondary working fluid; and wherein the primary heat tube and the secondary tube supports are integral with the housing, and wherein the housing is configured with an end plate at its respective ends, and wherein the primary heat tube comprises a coupling arrangement at each end plate, couplable with a primary heat tube of a coextending like solar heat collector module, and the secondary heat tubes comprise a coupling arrangement at each end plate, couplable with secondary heat tubes of a coextending like solar heat collector module, wherein the solar heat collector modules are couplable to one another at a coextensive configuration, wherein fluid flows between coextending primary heat tubes and coextending secondary heat tubes.

According to still an aspect of the disclosure there is a solar heat collector comprising a housing, optionally a trough-like housing, defining a radiation space extending along a longitudinal axis and comprising inside wall surfaces; a primary heat tube extending within the radiation space near a base of the trough and is intended for carrying a primary fluid; a plurality of secondary tubes extending along the radiation space and is intended for carrying a secondary working fluid, external to said primary heat tube and below an aperture of the housing; and wherein the primary heat tube and the secondary tubes are integral with the housing.

Yet another aspect of the present disclosure provides a system for allowing heat transfer between an agricultural module and a solar heat collector module. The heat collector module comprises a housing, optionally a trough-like housing, defining a radiation space extending along a longitudinal axis and comprising inside wall surfaces; a primary heat tube extending within the radiation space near a base of the trough and is intended for carrying a primary working fluid; a plurality of secondary tube supports extending along the radiation space, external to said primary heat tube and below an aperture of the housing, each configurable for supporting a secondary heat tube, or optionally supporting a secondary heat tube that is intended to carry a secondary working fluid; and wherein the primary heat tube and the secondary tube supports are integral with the housing. The agricultural module comprises a growing tray configured to facilitate a growing bed for enabling the growth of plants; and a water collecting tank configured to store water therein, wherein said water collecting tank is positioned beneath said growing tray to enable water to drain from said tray to said tank. The secondary heat tubes extend between the radiation space and the water collecting tank to allow heat transfer between heat being collected in the portion of the secondary tubes disposed within the radiation space and water in the water collecting tank. Namely, the secondary working fluid is heated in the radiation space and flows to transfer the heat to the water in the water collecting tank. The primary heat tube extends between the radiation space and an outlet positioned in at least one of: (i) surrounding of the agricultural module, (ii) such that it is directed to a portion of the growing tray, and/or (iii) between the growing tray and the water collecting tank. This allows to heat the air surrounding the plants growing in the agricultural module to obtain desired air temperature that is suitable for the growing of the plants. This is specifically important during cold days.

Any one or more of the following features, designs and configurations, can be applied to any one or more of the aspects of the present disclosure, solely or in various combinations thereof:

• The plurality of secondary tube supports can extend coplanar, parallel to a plane defined by the aperture of the housing;

• At least two secondary tube supports are each configured with a support leg extending from a respective side wall of the housing;

• One or more of the secondary tube supports can extend from an external wall surface of the primary heat tube;

• Two or more neighboring secondary tube supports can be interconnected with one another by a heat absorbing surface;

• The heat absorbing surface can be integral with the secondary tube supports, or with support legs of the secondary tube supports; • The secondary tube supports can be configured for cradling at least a portion of the secondary heat tubes;

• Inside wall surface and portions of the housing can be colored or coated with a heat absorbing layer;

• Inside surfaces of any of the primary heat tube secondary heat tubes can be made of, or coated with, or comprise a layer of biocompatible material, or material compatible for carrying the fluid intended for flowing within a respective tube;

• The secondary heat tubes can be tubular members articulated to the secondary tube supports;

• The secondary heat tubes can be integral with the secondary tube supports;

• A gap can extend between two or more neighboring secondary tube supports, facilitating direct radiation to the primary heat tube disposed therebelow;

• The secondary heat tubes can be made of Cross-linked polyethylene (PEX pipes);

• Heat transfer of the primary heat tube is facilitated mainly through convection and conduction;

• Heat transfer of the primary heat tube can be enhanced by radiation through apertures configured at the heat absorbing surface between two or more neighboring secondary tube supports;

• Heat transfer of the secondary heat tubes is facilitated through radiation, convection and conduction;

• Primary heat tube can be axially divided giving rise to two or more primary heat tubes;

• The primary heat tube can have a circular cross section;

• A portion of a wall of the primary heat tube can be an inside wall portion of the housing;

• The primary heat tube can have a composite cross section formed out of wall segments;

• The primary heat tube can comprise polygonal and/or round sectioned wall segments;

• The housing aperture can be covered by a transparent cover;

• The cover can be a single planar panel of material spanning over the housing aperture; • The cover can be glass;

• The housing can be configured with a heat insolating layer disposed external to said inside wall;

• The heat insolating layer can extend between the inside wall and an outside wall; · The inside wall and the outside wall can extend parallel to one another;

• The outside wall can be integral with the housing or it can be attached thereto, at a spaced apart distance from the inside wall;

• The secondary heat tubes can be retained in place over the secondary tube supports by a clamping member clamping ends of the secondary heat tubes over the respective end plate;

• The secondary heat tubes can be snugly received within a cradling portion of the secondary tube supports, with surface contact therebetween;

• The trough-like housing can have a cross section of an isosceles trapezoid;

• The trough-like housing can have a triangular cross section; · The housing with the integral primary heat tube and the integral secondary tube supports can be an extruded structure;

• The plurality of secondary heat tubes can be attached with fasteners to the secondary tube supports. The fasteners can be configured as snap-type fasteners, such as clips; · The plurality of secondary heat tubes can be configured as parallelly disposed tubes or as a continuous one or more undulating pipes;

• A radiation space extends within the housing, covered by a transparent cover, and wherein said primary heat tube and plurality of secondary heat tubes are disposed within said radiation space; · The plurality of secondary heat tubes can coextend between neighboring solar heat collector modules, or at least some of the plurality of secondary heat tubes of a first solar heat collector module can be articulated to at least some of the plurality of secondary heat tubes of a neighboring solar heat collector module by a manifold;

• Fluid within the radiation space can flow between neighboring heat collector modules of a solar heat collector system;

• Fluid within the primary heat tube and the radiation space can flow through a manifold disposed at respective ends of a heat collector module; • The coupling arrangement between primary heat tubes of neighboring solar heat collector modules can be a male/female coupler disposed at respective ends of the primary heat tubes;

• The coupling arrangement between secondary heat tubes of neighboring solar heat collector modules can be a male/female coupler disposed at respective ends of the primary heat tubes;

• At least the primary heat tube can be symmetrically disposed within the housing;

• The collector housing can have a substantially parabolic cross section;

• The collector housing can have a substantially right-angle cross section;

• The collector housing can have two side walls disposed at a right angle with respect to one another;

• The side walls of the collector housing can be of equal length or can each have a different length;

• An aperture plane of the collector housing can be planar;

• An aperture plane of the collector housing can be a flat plane;

• An aperture plane of the collector housing can be a concave plane;

• An aperture plane of the collector housing can be composed of two intersecting planes, each having a different aperture angle;

• At least one external wall portion of the housing is flat and configured for wall surface mounting;

• The at least one primary fluid and the at least one secondary fluid, can be the same fluid;

• The secondary tube supports can be configured with laterally extending winglets for heat exchange enhancement;

• The housing can be an integrally configured, during an extrusion manufacturing process, with fastener receptacles. Such fastener receptacles can be useful for attaching end plates at respective ends of the solar heat collector, for wall mounting attachments, etc.;

• Elements of the solar heat collector system can be made of materials having similar thermal expansion coefficient or the solar heat collector system can be configurable with expansion elements disposed between elements having different thermal expansion coefficient, to thereby compensate for thermal expansion of neighboring elements. Alternatively, some elements of the system are configured for absorbing thermal expansion of neighboring elements.

• The primary heat tube and the secondary heat tubes are in thermal communication at least within the radiation space. Namely, the primary heat tube and the secondary heat tubes can exchange heat at least within the radiation space.

• The primary heat tube is carrying gas, typically air. The air is discharged in a desired location to heat the air in the surrounding of plants.

• The agricultural module comprises a photovoltaic cell positioned over said growing tray, configured to produce photovoltaic energy.

• The secondary heat tubes are forming a closed loop such that the secondary working fluid flows in said closed loop. The primary heat tube has an open end at the outlet and the air that flows therein is received from at least one air receiving portion of the primary heat tube and discharged through the outlet. The radiation space is positioned between the air receiving portion and the outlet.

• The flow path of the closed loop of the secondary heat tubes comprises a portion that is in thermal communication with a target medium to be heated, different than the portion resides within the radiation space.

• The system comprises a pump for pumping the secondary working fluid from the portion of the secondary heat tube positioned within the water collecting tank to the radiation space.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to better understand the subject matter that is disclosed herein and to exemplify how it may be carried out in practice, embodiments will now be described, by way of non-limiting example only, with reference to the accompanying drawings, in which:

Fig. 1 is a solar heat collector system according to an example of the disclosure, mounted on a wall;

Fig. 2 is a solar heat collector module used in the system of Fig. 1 ;

Fig. 3A is a section taken along line III - III in Fig. 2;

Fig. 3B is a planar side view of Fig. 3A;

Fig. 4A is a perspective view of a housing of a solar heat collector according to an example of the disclosure; Fig. 4B is a planar side view of Fig. 4A;

Fig. 5A is a perspective view of the portion marked V in Fig. 2;

Fig. 5B is a section along line V - V in Fig. 5A;

Fig. 5C is the same as Fig. 5Bm however with a cover of the housing removed;

Fig. 5D is an enlargement of the portion marked 5D in Fig. 5C;

Fig. 6 is an enlargement of a portion sectioned along line VI - VI in Fig. 1;

Fig. 7 is a perspective view of a solar heat collector module, according to another example of the disclosure;

Fig. 8A is section along line VIII - VIII in Fig. 7;

Fig. 8B is a planar side view of Fig. 8A;

Fig. 9A is the same as Fig. 8A, however with a front cover removed;

Fig. 9B is a planar side view of Fig. 9A;

Fig. 10 is a perspective exploded view of an end portion of the solar heat collector module of Fig. 7;

Fig. 11A illustrates a retaining arrangement, according to a first example, for securing the secondary heat tubes over an end plate, at a secured position;

Fig. 11B is an assembly step for securing retaining arrangement of Fig. 11A;

Fig. 12A is a perspective view of a retaining arrangement, according to a second example, for securing the secondary heat tubes over an end plate, at a secured position;

Fig. 12B is a planar side view of Fig. 12A;

Fig. 12C is an assembly step for securing retaining arrangement of Fig. 12A;

Fig.l3A is a perspective view of a solar heat collector module according to the disclosure, configured with an end manifold;

Fig. 13B is an enlargement of the portion marked 13B in Fi. 13A;

Fig. 13C is the same as Fig. 13B, with the manifold removed;

Fig. 13D is the same as Fig. 13B, with the glass cover, end plate and manifold removed;

Fig. 13E is an exploded view of only the end plate and the end manifold; and

Fig. 13F is an end view in direction of arrow 13F in Fig. 13 A, illustrating an end filtration unit configured at the end plate of the solar heat collector module.

Figs. 14A-14B are schematic illustrations of different views of a non-limiting example of a system comprising an agricultural module and a solar collector module according to an aspect of the present disclosure. Fig. 14A is a perspective view and Fig. 14B is a cross sectional view. DETAILED DESCRIPTION OF EMBODIMENTS

Attention is first directed to Figs. 1 and 2 of the drawings, illustrating a modular solar heat collector system, generally designated 10, which in the example of Fig. 1 comprises two solar heat collector modules 12A and 12B (12 in Fig. 2). The solar heat collector system 10 is attached to a wall 14, as will be discussed hereinafter. It is noted however, that wall mounting is a mere example and accordingly, the solar heat collector system is configurable for roof mounting, mounting over support posts, different constructions, buildings, surfaces, etc.

With further reference now being made also to Figs. 3A to 5D, a solar heat collector module 12 according to a first example of the disclosure comprises a trough- like housing 20, typically made of extruded metal such as aluminum, and the like, said housing defining a radiation space 22 extending along a longitudinal axis 24 and comprising inside wall 26. An outside wall 28 is attached to the housing, spaced apart from the inside wall 26, and defining a thermally insulating space 30 between the inside wall 26 and the outside wall 28. In the illustrated example the insulating space 30 accommodates a thermal insulating material 30 (e.g. foamed material such as Polyurethane, mineral wool, or said space can be under vacuum). It is appreciated that the outside wall 28 can be integrally extruded or otherwise attached to the housing 20, for example by support arms 29 extending from a back side of the housing 20.

It is seen that the housing 20 has a cross section of an isosceles trapezoid, having two flat wall portions 23A and 23B disposed at a right angle, with an inclined connecting wall portion 23C, with respective parallel outside walls 25A and 25B. However, it is appreciated that housing can assume any different shapes, such as a parabolic (or other round shapes), triangular (e.g. a right-angle triangle), etc., not shown. The housing 20 is configured at its respective axial ends with an end plate 27 (Fig. 5A). The housing 20 has an aperture extending between two parallel facing longitudinal edges 34 thereof. As will become apparent hereafter, the aperture is covered by a transparent cover 38, typically made of clear glass. The housing 20 is configured with an integrally formed primary heat tube 42, extending within and along the radiation space 22 near a base portion 40 of the trough housing, said primary heat tube 42 having a circular segment 46 and some linear segments, being part of the inside wall 26. Whilst in the present example the primary heat tube 42 has an irregular cross section shape, it is appreciated that many other shapes can be configured. For example, in Fig. 8 and 9 the primary heat tube has a round cross section. Even more so, whilst in the present example the primary heat tube 42 is a unitary tube, it is appreciated that the primary heat tube can be divided so as to comprise two, or more, primary heat tubes (e.g. primary heat tubes 43A and 43B schematically exemplified by a dashed line 45 dividing the primary heat tube 42.

It can be seen that respective ends of the primary heat tube 42 (namely an inlet port and an outlet port, respectively) project from the end plate 27 of the housing 20, such that primary heat tube 42 of adjoining solar heat collector modules can be coupled in a flow communicating manner to one another. For that purpose, an inlet port and an outlet port of each primary heat tube 42 is configured with a coupling arrangement which in the illustrated example are a male/female coupler, which as can be seen (Fig. 6) a male-type coupler 47 of a first solar heat collector modules 12A is couplable with a female-type coupler 49, of a second solar heat collector modules 12B, in fluid impermeable manner.

The housing 20 is configured with a plurality (six in the illustrated example) of integrally formed secondary tube supports 50 extending along the radiation space 22, parallel with the longitudinal axis 24, said secondary tube supports 50 being trough-like elements, disposed parallel with one another and inclined at an angle a with respect to a normal of the flat wall portion 23B. Noting that the hosing 20 has a cross section of an isosceles trapezoid, the secondary tube supports 50 are symmetrically disposed over a flat plane.

As noted, best in Fig. 4B, several of the secondary tube supports 50 are supported from flat wall portions 23A and 23B and from the circular segment 46 of the primary heat tube 42 by support legs 54 and 56, respectively. Also seen, some of the secondary tube supports 50 are connected to neighboring secondary tube supports 50 by an integral heat absorbing surface 57, whilst a center pair of the secondary tube supports 50 are not connected to one another, thus leaving a gap 55 therebetween, said gap 55 disposed over the primary heat tube 42, thus enhancing radiation to the primary heat tube 42. Each secondary tube support 50 is configured with longitudinal, laterally extending winglets 60 for heat exchange enhancement, and for articulation thereto of a secondary heat tube, as will be explained.

Each of the secondary tube support 50 is configured for snuggly receiving a secondary heat tube 64, whereby portions of the secondary heat tube 64 are in surface contact with portions of the secondary tube support 50, for enhancing heat transfer therebetween. The secondary heat tubes 64 can be made of any suitable material, setting as an example Cross-linked polyethylene (PEX pipes).

It should be realized that the secondary heat tubes 64 can be a plurality of unitary pipes extending across the housing, each coupled at one end thereof to a fluid inlet (not shown) and at a second end to a fluid outlet (not shown), or the secondary heat tubes 64 can be coupled at one end to a fluid inlet manifold (not shown) and at a second end to a fluid outlet manifold (not shown), or there can be a unitary (one or more) secondary heat tube, having an inlet port and an outlet port and undulating within the housing (not shown) and placed over the secondary tube supports 50.

The secondary heat tubes 64 extend from the end plate 27 such that secondary heat tubes 64 of adjoining solar heat collector modules can be coupled in a flow communicating manner to one another. For that purpose, an inlet port and an outlet port of each secondary heat tube 64 is configured with a coupling arrangement 68 (Fig. 6), such as a quick pipe coupling arrangement, threaded coupling, etc.

As can be seen in Fig. 5D, each of the secondary heat tubes 64 is snugly placed over a cradling secondary tube support 50 and is articulated thereto by a clip 72 snap- fastened over the lateral winglets 60 of the secondary tube support 50, thereby securing the secondary heat tubes 64 and ensuring optimal thermal transfer therebetween.

At the assembled position, and as can be seen for example in Figs. 5A - 5C, the secondary heat tubes 64 are disposed below the aperture of the housing 20, whereby the clear glass cover 38 is disposed slightly above said secondary heat tubes 64.

As seen (for example in Fig. 3B), the glass cover 38 is a flat panel, secured to the parallel facing longitudinal edges 34 of housing 20 by two opposite longitudinal receptacles 78, facing each other and accommodating an edge of the glass panel and a sealer strip 80 (sealing the radiation space 22 and also facilitating for thermal expansion of the glass panel). The end plates 27 are secured to the housing 20 by several threaded fasteners (screws 82) screw coupled into threaded receptacles 84 integrally configured with the extruded housing.

Inside wall surfaces of the housing 20, namely of the radiation space 22, are colored or coated with a heat absorbing layer, typically black colored, for enhancing solar heat absorbing. Furthermore, inside surfaces of any of the primary heat tube 42 and secondary heat tubes 64, can be made of, or coated with, or comprise a layer of biocompatible material, or material compatible for carrying the fluid intended for flowing within a respective tube.

The extruded housing 20 is further configured with mounting slots 88A and 88B, for slidingly receiving a T-shaped fastener 90 (e.g. a bolt) which in turn is secured to a L- shaped wall mounting bracket 92, securable to a wall 14 (or over a surface; not shown).

A locking end plate 94 is disposed at each respective axial end of the housing 20, said locking end plate 94 configured for clamping the secondary heat tubes 64 over the end plate 27 and for preventing axial displacement of the glass panel 38. The locking end plate 94 is secured to the housing 20 by a screw fastener 95 at one side (an up-side thereof), and by an undercut (male -female like) articulation 96 at an opposite end thereof.

It should be realized that elements of the solar heat collector system can be made of materials having similar thermal expansion coefficient or the solar heat collector system can be configurable with expansion elements disposed between elements having different thermal expansion coefficient, to thereby compensate for thermal expansion of neighboring elements. Alternatively, some elements of the system are configured for absorbing thermal expansion of neighboring elements. For example, the secondary heat tubes are made of polymeric material, and theses are placed over aluminum made secondary tube supports, whereby thermal expansion therebetween can be tolerated.

Turning now to Figs. 7 to 12C of the drawings, there is illustrated solar heat collector system, generally designated 110, being a modification of the disclosure. For sake of simplicity, elements similar with those of the previous example, are designated with like reference numbers, however shifted by 100.

The main difference between the two solar heat collector systems 10 and 110 resides in the shape of the housing, though following the same principals. In particular, it is seen that housing 120 of the second example, has a trough-like shape composed of two walls 123A and 123B disposed at a right-angle with respect to one another, however wherein the former wall 123A is longer than the later wall 123B, and having a round connecting portion 123C. It is seen that the round portion is a segment of a primary heat tube 142 having a circular cross section. The housing 120 is further configured with several integral support arms 129 extending at a back side of the housing and configured for supporting a thermal insulating material 130. The thermal insulating material 130 can be a board of material supported by said support arms 129 (as illustrated in the drawings, or it can be applied between the walls 123 and an outside wall 131).

A plurality (six in the illustrated example) of secondary tube supports 150 are disposed within the housing 120, parallel to one another and to a longitudinal axis 124 of the housing. Each secondary tube support 150 is supported over a respective support leg

154 extending from the walls 123A and 123B and from an external surface of the primary heat tube 142 (though one of the secondary tube supports 150 extends directly articulated to said an external surface of the primary heat tube 142). In this example, unlike the previous example, neighboring secondary tube supports 150 are not interconnected with one another (by heat absorbing surface, as some of the secondary tube supports in the previous example), whereby the primary heat tube 142 is exposed to radiation between the secondary tube supports 150. The secondary tube supports 150 are set in two planes

155 and 157, disposed at an angle b therebetween (Fig. 8B), and wherein each secondary tube supports 150 is configured with longitudinal, laterally extending winglets 160 for heat exchange enhancement, and for articulation thereto of a secondary heat tube. Snugly supported over a cradling portion of each of the secondary tube supports 150 there is a secondary heat tube 164 retained by a clip (for example such as clip 72 in the previous example), whereby portions of the secondary heat tube 164 are in surface contact with portions of the secondary tube support 150, for enhancing heat transfer therebetween. The secondary heat tubes 164 can be made of any suitable material, setting as an example Cross-linked polyethylene (PEX pipes).

The radiation space 122 is covered by two clear glass panels 138A and 138B disposed over intersecting planes 155 and 157, each secured between two opposite longitudinal receptacles 178, facing each other and accommodating an edge of the glass panel and a sealer strip 180 (sealing the radiation space 122 and also facilitating for thermal expansion of the glass panel).

A locking end plate 194 is disposed at each respective axial end of the housing 120, secured to the housing 120 by several threaded fasteners (not shown) extending through openings 183 at end plates 194, and screw coupled into threaded receptacles 184 integrally configured with the extruded housing 120.

The locking end plate 194 is configured for clamping the secondary heat tubes 164 over the end plate 127 and for preventing axial displacement of the glass panels 138A and 138B. The locking end plate 194 is secured to the housing 120 by a screw fastener 195 applied through aperture 197 (Fig. 12A) at one side (an up-side thereof), or by a snapping arrangement 195 (as in figs. 11A and 1 IB).

As discussed hereinbefore, respective ends of the primary heat tube 142 (namely an inlet port and an outlet port, respectively) project from the end plate 127 of the housing 120, such that primary heat tube 142 of adjoining solar heat collector modules can be coupled in a flow communicating manner to one another. For that purpose, an inlet port and an outlet port of each primary heat tube 142 is configured with a coupling arrangement, couplable with a coupling arrangement a second solar heat collector module.

It is appreciated, similar to the previous example, that the secondary heat tubes 164 can be a plurality of unitary pipes extending across the housing, each coupled at one end thereof to a fluid inlet (not shown) and at a second end to a fluid outlet (not shown), or the secondary heat tubes 164 can be coupled at one end to a fluid inlet manifold (not shown) and at a second end to a fluid outlet manifold (not shown), or there can be a unitary (one or more) secondary heat tube, having an inlet port and an outlet port and undulating within the housing (not shown) and placed over the secondary tube supports 150.

The secondary heat tubes 164 extend from the end plate 127 such that secondary heat tubes 164 of adjoining solar heat collector modules can be coupled in a flow communicating manner to one another. For that purpose, an inlet port and an outlet port of each secondary heat tube 164 is configured with a coupling arrangement (not shown), such as a quick pipe coupling arrangement, threaded coupling, etc.

Other features and parameters discussed and explained in connection with the previous example can apply also in connection with the present embodiment, and reference is directed thereto.

Further attention is now made to Figs. 13A to 13F of the drawings illustrating a solar heat collector module generally designated 170, being substantially similar with solar heat collector modules discussed hereinabove, however with some new features disclosed.

The housing 172 of the solar heat collector module 170 is configured with a first end plate 176 and a second end plate 178, wherein the second end plate (best seen in Figs. 13C and E) serves as a collecting end plate configured for collecting fluid flowing within the primary heat tube 180 and fluid within the radiation space 182 into a common outlet port 188 of end plate 178, with manifold 192 mounted thereover. The manifold 192 is configured with a male-type outlet tube coupler 194 (similar with male-type coupler 47 seen in Fig. 6), couplable with a female-type coupler of a neighboring solar heat collector modules (not shown).

Fig. 13F illustrates the first end plate 176, configured with an end filtration unit 195 disposed within the end plate.

Other features and parameters discussed and explained in connection with the previous examples can apply also in connection with the present embodiment, and reference is directed thereto.

Figs 14A-14B are schematic illustrations of different views of a non-limiting example of a system comprising an agricultural module and a solar collector module according to an aspect of the present disclosure. In this example, the system 251 comprising three agricultural modules 250A, 250B and 250C and three solar collector modules 252A, 252B, 252C housed together. It is to be noted that this is just an example of the number of modules housed together and the system can include any number of agricultural modules and solar collector modules from one and on. The system can also comprise an uneven number of agricultural modules and solar collector modules. Each of the solar collector modules comprises a radiation space that houses a portion of a primary heat tube 254, carrying air, and a portion of secondary heat tubes 256, carrying a secondary working fluid. The solar collector modules are connected one to the other such that the primary and the secondary heat tubes extend continuously along them.

Each of the agricultural modules comprises (i) a growing tray 258 for facilitating growing bed for enabling the growth of plants, (ii) a water collecting tank 260 below the growing tray to contain water and (iii) a photovoltaic cell 262 positioned over said growing tray 258, configured to produce photovoltaic energy. The solar collector modules 252 are also disposed over said growing tray, adjacent to the photovoltaic cells 262. The primary heat tube extends from the radiation spaces of the solar collector modules 252 to three outlets 264, each in a different agricultural module 250. In this example, the outlets 264 of the primary heat tube are positioned between the water collecting tank 260 and the growing tray 258 of each agricultural module 250. It is to be noted that the outlets can be positioned at various positions in or in the surrounding of the agricultural modules.

The secondary heat tubes 256 are forming a closed loop that a portion thereof is disposed in each of the water collecting tanks of the agricultural modules 250, therefore allowing heat transfer between the radiation space and the water collecting tank, i.e. the water in the water collecting tank. The secondary working fluid is pumped from the water collecting tank to the radiation space by a pump (not shown) to allow the closed loop flow.

While not exemplified in this example, it is to be noted that, optionally, the agricultural modules can be connected in at least one of the following ways: (i) series or parallel connection of the photovoltaic cells and/or (ii) connection between two adjacent water collecting tanks via water ports allowing flow of water between different water collecting tanks.