WO2021204921A1

WO2021204921A1 - Structure for hydroponic cultivation

Info

Publication number: WO2021204921A1
Application number: PCT/EP2021/059130
Authority: WO
Inventors: Staffan MATZÉN; Sarosh RAMACHANDRA
Original assignee: Eko Groenovation AB
Current assignee: Eko Groenovation AB
Priority date: 2020-04-08
Filing date: 2021-04-08
Publication date: 2021-10-14
Anticipated expiration: 2022-10-08
Also published as: SE545686C2; SE2050404A1

Abstract

A structure (101, 102, 103, 200, 300, 400, 500, 601) for hydroponic cultivation, comprising a hollow body (110, 210, 310, 410, 510, 610) elongating along a first axis, A, and a plurality of holding members (120, 220, 320, 420, 520, 620) integrally formed with the hollow body and arranged along a second axis, B, parallel to the first axis, A. Each holding member is arranged to hold a growth substrate (390, 491, 492, 590, 690) via a respective opening (330) of the hollow body wherein the hollow body provides a passage (130, 230, 330, 430, 530) arranged along the second axis and between the plurality of holding members. The passage is such that, in a vertical arrangement of the structure, droplets (395, 495, 641) released from a first holding member (221, 321, 421, 521) are arranged to drip in the passage towards a second holding member (222, 322, 422, 522) adjacently arranged below the first holding member.

Description

STRUCTURE FOR HYDROPONIC CULTIVATION

FIELD OF THE INVENTION

The present invention generally relates to hydroponic growing and cultivation of plants. More specifically, the present invention is related to a structure or arrangement of structures for hydroponic cultivation.

BACKGROUND OF THE INVENTION

Hydroponic cultivation of various types of crops has attracted and continues to attract attention. The growing interest for hydroponic cultivation stems in part from the increasing demand for locally grown produce, which may be more easily met all year around when growing hydroponically. Compared to soil-based cultivation and greenhouse cultivation, hydroponics provides numerous advantages such as the ability to grow crops anywhere regardless of the season or climate, a sterile environment requiring no pesticides and the reuse of system water and nutrients to reduce the total volume of water used for growing crops.

In particular, there is currently an interest in growing crops vertically in order to be space efficient when resourcing to hydroponic cultivation. Such vertical structures permit a higher volume of plants to be grown in a limited space and in liquid nutrients therefore eliminating manipulation of soil of any kind and increasing the harvesting frequency.

However, current hydroponic systems suffer from nutrient distribution deficiency across all plants wherein groups of plants receive a greater amount of nutrient and water than groups of plants located further in the system. In addition, the reuse of water and the closed-loop water feeding systems currently presented in the prior art may result in problematic accumulation of algae, loss of water and nutrients through evaporation and/or splattering and increased humidity in the system and its surroundings.

Hence, it is an object of the present invention to try to overcome at least some of the deficiencies of present hydroponic cultivation systems regarding nutrient deficiency, increased humidity and/or loss of water in the system.

SUMMARY OF THE INVENTION

Hence, it is of interest to overcome at least some of the deficiencies of present hydroponic cultivation systems, in order to improve the distribution of nutrients throughout the plants and to improve the retention of water in the system. This and other objects are achieved by providing a structure for hydroponic cultivation having the features in the independent claim. Preferred embodiments are defined in the dependent claims.

Therefore, according to a first aspect of the present invention, there is provided a structure for hydroponic cultivation, comprising a hollow body elongating along a first axis and a plurality of holding members integrally formed with the hollow body and arranged along at least one second axis parallel to the first axis. Each holding member is further arranged to hold a growth substrate via a respective opening of each holding member. It will be appreciated that the respective opening of each holding member may be also be understood as respective openings of the hollow body. Moreover, the hollow body provides a passage arranged along the second axis and between the plurality of holding members. The passage is such that, in a vertical arrangement of the structure, droplets released from a first holding member of the plurality of holding members are arranged to drip in the passage towards a second holding member of the plurality of holding members, adjacently arranged below the first holding member. Furthermore, according to a second aspect of the present invention there is provided an arrangement for hydroponic cultivation, comprising at least one structure according to the first aspect and a plurality of growth substrates wherein each holding member of the at least one structure is arranged to hold a respective growth substrate of the plurality of growth substrates.

Thus, the present invention is based on the idea of providing a structure wherein the flow of nutrient solution comprising water and nutrients reaches and at least partially traverses each growth substrate in such way that the waste of water and nutrient between each growth substrate is minimized and the desired retention of nutrients of each growth substrate is obtained. The structure of the present aspects is therefore based on the idea of optimization of growth yield in relation to system input. In other words, an object of the present invention resides in the maximization of re-utilization of water and nutrients from one growth substrate to the subsequently arranged growth substrate throughout the entire structure.

The present invention is hereby advantageous in that the hollow body of the structure and the plurality of holding members integrally formed with said hollow body provide an ample volume within which plant or crop roots stemming from the growth substrates may grow without directional restriction ultimately resulting in a greater yield of the plant growth. Furthermore, the ample volume comprised within the hollow body and holding members also allows for adequate aeration of the growth substrates and roots generated therefrom thus resulting in the reduction of humidity in the hollow body and plurality of holding members as well as a better growth yield. The space defined by the hollow body further prevents the roots from clogging the structure therefore ensuring efficient dripping of nutrient solution form one holding member to a subsequently arranged one. In addition, the integrality of the plurality of holding members with the hollow body allows the structure to be manufactured by, but not limited to, means of blow molding techniques thus rendering the structure, particularly the junctures between the holding members and the hollow body, more resistant. Furthermore, the complexity of the structure is minimized by reducing the number of components needed for its production.

The plurality of holding members may furthermore be arranged on several sides of the hollow body, i.e. across its surface area and parallelly to the first axis of said hollow body therefore maximizing the amount of plants to be grown on a single structure. The number of holding members along a same axis may be arbitrary depending on the species or type of plant or crop grown on the structure. For example, plants requiring more space when growing may be accommodated by a structure on which the plurality of holding members are more distant in contrast to a lesser expanding plant. In addition, the present invention permits the root system of the plants (i.e. leaves, branches, nodes, etc.) to extend out from the hollow body through the holding members’ relative openings resulting in unobstructed photosynthesis of each plants.

The present invention is further advantageous in that the passage provided by the hollow body between the plurality of holding members along their second axis allows for a maximum of the nutrient solution shed from a growth substrate to be directed towards the holding member arranged subsequently thereafter. This construction or design of the structure results in the minimization of waste of said nutrient solution, in turn resulting in a lesser volume of nutrient solution to be required by the structure for effective growth of the crops. The maximization of re-utilization of nutrient solution throughout the plurality of holding members of the structure further allows for an efficient and even distribution of nutrient amongst the growth substrates held by each holding member of the plurality of holding members.

The present invention is further advantageous in that the reduction of the required volume of nutrient solution to be used permits a shorter time between harvests of plant or crops held in a structure thus resulting in a more continuous harvesting of the structure and a larger volume of plant produced. The present invention permits the nutrient solution, administered to the growth substrate held in a first holding member of the structure, to travel towards an adjacently arranged second holding member, below the first holding member, either directly by dripping from one growth substrate onto the adjacent one or indirectly by circulating via the surfaces of the hollow body and holding member comprised in the passage. The present invention is therefore advantageous in that it allows for a maximum amount of nutrient solution to be transferred from one growth substrate to another rendering the control of said nutrient solution very efficient in terms of its composition and the required volume.

There is provided a structure for hydroponic cultivation, comprising a hollow body elongating along a first axis, A, a plurality of holding members integrally formed with the hollow body and arranged along at least one second axis parallel to the first axis, wherein each holding member is arranged to hold a growth substrate via a respective opening of each holding member. It will be appreciated that the respective opening of each holding member may be also be understood as respective openings of the hollow body. By the term “growth substrate” is here meant a growing support material or medium for growing a plant or a crop without the use of soil such as, but not limited to, coconut coir, growstones, expanded clay aggregate, perlite etc. The hollow body provides a passage arranged along the second axis and between the plurality of holding members. By the term “passage” is here meant a passage or path formed within the hollow body of the structure, in which passage a fluid may pass. In a vertical arrangement of the structure, droplets released from a first holding member of the plurality of holding members are arranged to drip in the passage towards a second holding member of the plurality of holding members, adjacently arranged below the first holding member. Hence, droplets (e.g. of water, nutrient, and/or a combination thereof) may pass from a first holding member to a second holding member arranged below the first holding member, under the influence of gravity. Alternatively, there may be an at least partially continuous flow of fluid comprising e.g. water, nutrient, and/or a combination thereof which may pass from the first holding member to the second holding member. By the term “vertical arrangement”, it is understood that the structure may be arranged vertically or even (slightly) inclined with respect to a vertical axis.

According to an embodiment of the present invention, each holding member may elongate along a third axis, forming an angle a with the first axis. In other words, the holding members may be inclined with respect to the elongated hollow body of the structure.

It will be appreciated that the openings of the hollow body, respective to each holding member, are aligned and concentric with the third axes. The present embodiment is therefore advantageous in that it allows the openings of the hollow body to also form an angle with the first axis of the hollow body allowing sufficient space for the plants growing from each growth substrate to extend out from the holding members and grow adequately. Moreover, the angle a formed between the third axes of the holding members and the first axis of the hollow body allow for each growth substrate to also be held at the same angle a within said hollow body. The arrangement of the holding members of the structure at an angle a is therefore advantageous in that it allows growth substrates held by adjacently arranged holding members to share a greater surface alignment along the second axis thus increasing the capacity of a growth substrate to receive nutrient solution being released or shed from a preceding growth substrate. The present embodiment is further advantageous in that the arrangement of the holding members of the structure at an angle a prevents nutrient solution from accumulating in each holding member or growth substrate and rather provides a slope in the structure directing the nutrient solution to the adjacently arranged holding member and growth substrate. The angle a therefore allows for a better distribution of the nutrients among all growth substrates held in the structure and prevents losses of nutrient solution and water through evaporation.

According to an embodiment of the present invention, the angle a may be in the range of 15°-75°, preferably 20°-70° and most preferred 35°-45°. In other words, the holding members may be inclined with respect to the elongated hollow body of the structure by the angle(s) as exemplified. The present embodiment is advantageous in that it may provide an optimum arrangement of plants or crops held within the holding member with respect to growth efficiency, cultivation automation, etc. The present embodiment is further advantageous in that it prevents each holding member and their respectively held growth substrate from being arranged upright, i.e. parallel to the first axis of the hollow body, which may impede an efficient growth and deteriorate an automation of the cultivation. The present embodiment is further advantageous in that it also prevents each holding member and their growth substrate to be arranged perpendicular with said first axis thus preventing undesired accumulation of nutrient solution in the holding members. It will be appreciated that the angle may vary depending of the crop grown and desired harvesting size of said crop. The above recited range of the angle a allows for a prosperous growth of the plants with enough exiting space from the holding members through the openings.

According to an embodiment of the present invention, the structure may further comprise a first protrusion pattern comprising at least one protrusion arranged in the passage and protruding inwardly toward the first axis, A, such that, in a vertical arrangement of the structure, the first protrusion pattern may be arranged to direct droplets, released from a first holding member, towards a second holding member, in a first path of the passage. It will be appreciated that the at least one protrusion arranged in the passage and protruding inwardly toward the first axis, A, may also be understood as protruding toward the center of the hollow body. In a particular embodiment, the droplets released from the first holding member may be arranged to drip onto the growth substrate, held by the second holding member, via the first protrusion pattern. The present embodiments are advantageous in that they permit an increased re-utilization of nutrient solution between adjacently arranged holding members thus enabling a structure which requires a lesser volume of nutrient solution to reach efficient cultivation of crops. Furthermore, the at least one protrusion of the first protrusion pattern allows any droplets of nutrient solution accumulated on the inner surface of the hollow body of the structure to be redirected to the subsequently arranged holding member which prevents any droplets from simply traveling down the center of the hollow body or evaporating therefore skipping a growth substrate or even missing several of them. The first protrusion pattern is thus advantageous in that it enables a maximum of droplets of nutrient solution to be re-utilized from one holding member to another through redirection enabled by the first protrusion pattern through the first path of the passage. The present embodiment further yields to a better control over the nutrient intake of each growth substrate ultimately leading to adequate nutrient distribution throughout the holding members of the structure.

According to an embodiment of the present invention, in a vertical arrangement of the structure, droplets released from a first holding member may be arranged to drip directly onto the growth substrate, held by a second holding member, in a second path of the passage. As a result of the alignment of the plurality of holding members and the angle a formed by said holding members with the hollow body of the structure, at least part of the surface of a growth substrate held by a first holding member superimposes at least part of the surface of the growth substrate held by a second holding member. The present embodiment therefore allows the lowest point of a growth substrate shedding nutrient solution to be vertically aligned with at least part of the surface of the growth substrate held by the holding member adjacently arranged below. The second path may therefore be construed as a passage, path or corridor of the hollow body between the superimposed surfaces of two growth substrates held by adjacently arranged holding members. The present embodiment is therefore advantageous in that such direct dripping allows the nutrient solution to transfer from one holding member to another without any interference from obstacles thus maximizing the nutrient distribution throughout the structure. It will further be appreciated that the rapidity by which nutrient solution is transferred via direct dripping through the second path enables a greater conservation of nutrient concentration in the nutrient solution as there is no interference between the droplets and the structure. The present embodiment is therefore again advantageous in that it allows a greater nutrient distribution across the plurality of holding members and reduces the required volume of nutrient solution to be administrated to the structure.

According to an embodiment of the present invention, a first holding member of the plurality of holding members, adjacently arranged to a second holding member of the plurality of holding members, may comprise a flange portion arranged in the passage and adjacently to the opening of the second holding member, such that, in a vertical arrangement of the structure, droplets released from the first holding member may be arranged to drip towards the second holding member, in a third path of the passage. By the term “flange portion”, it is here meant a local indentation in the geometry of the holding member, e.g. positioned at the lowest point of said holding member’s geometry. The present embodiment is advantageous in that the flange portion permits nutrient solution located on the inner wall of the holding members to be directed onto the growth substrate held by the adjacently arranged holding member. The flange portion further ensures that the droplets of nutrient solution following the third path of the passage detaches from the inner wall of the holding member. The present embodiment therefore allows for a re-utilization of a maximum volume of nutrient solution from a first holding member to an adjacently arranged second holding member. The detachment of droplets of nutrient solution provided by the flanged portion of the holding members further allows for the reduction of losses of nutrient solution through evaporation in turn resulting in a decrease of humidity in the structure.

According to an embodiment of the present invention, each holding member may further comprise a second protrusion pattern comprising at least one protrusion protruding inwardly toward the center of the holding member, wherein the second protrusion pattern may be arranged to hold the growth substrate. It will further be appreciated that the at least one protrusion of the second protrusion pattern may be shaped such that the contact area between the at least one protrusion and the growth substrate being held by said at least one protrusion be minimal. The present embodiment therefore allows adequate space for the root system growing from the growth substrate to grow radially and axially with minimum interference from the at least one protrusion. The present embodiment is further advantageous in that no additional material is needed to hold the growth substrates in position therefore enabling the complete structure to be manufactured by, but not limited to, blow molding techniques. The second protrusion pattern may further be oriented as to direct any residual nutrient solution comprised on the inner surface of the holding member towards the flanged portion, again resulting in greater re-utilization of the nutrient solution throughout the structure. Moreover, the second protrusion pattern allows the growth substrate to be held at different depths within the holding member in order to accommodate different sizes and shapes of growth substrates.

According to an embodiment of the present invention, the respective opening of the hollow body may comprise a rim such that each holding member is arranged to receive and to hold a substrate holder comprising a growth substrate. By the term “rim” it is here meant the section of the holding member determining its opening and being folded perpendicularly to the elongation axis of said holding member and inwardly to said opening. By the term “substrate holder” it is here meant a receptacle or enclosure arranged to contain the growth substrate and arranged to be detachable from the holding member and the structure. The present embodiment is advantageous in that the rim allows for nutrient solution splatter generated from the dripping between each holding member to be contained within each holding member. This retention of splatter enables once again the transfer of a greater volume of nutrient solution from one holding member to the adjacently arranged one throughout the entire structure. The present embodiment is further advantageous in that the rim may act as an abutment surface for the substrate holder therefore ensuring secure positioning of such substrate holder within the holding member. The substrate holders are further advantageous in that they facilitate the automation of the structure wherein the substrate holder is easily harvested and replaced by means of machinery thus resulting in a reduction of required labor to perform the cultivation of crops.

According to an embodiment of the present invention, the structure may comprise a hydrophobic material. The present embodiment is advantageous in that the hydrophobic material prevents any nutrient solution from being absorbed by the material forming the structure. The hydrophobic material of the structure herein presented further prevents the nutrient solution from adhering to the inner surface and diverging from the first, second or third path of the passage provided by the hollow body. The present embodiment therefore allows the nutrient solution to easily flow on or detach from the inner surface of the hollow body and holding members. The hydrophobic material further permits the reduction of the humidity in the structure.

According to an embodiment of the present invention, each growth substrate may be arranged in a substrate holder, and each holding member may be arranged to hold the respective growth substrate via the substrate holder. The present embodiment is advantageous particularly for automation of hydroponic cultivation. The substrate holders allow an increased facilitation of the removal and replacement of growth substrates in the structure rendering automation of the arrangement for hydroponic cultivation uncomplicated. Furthermore, the substrate holders may be interchangeable to adapt their enclosure to different sizes of growth substrates. The present embodiment further permits a quicker replacement of substrate holder in each holding members therefore enabling a quicker and more continuous harvesting.

According to an embodiment of the present invention, the substrate holder may comprise a bottom section which comprises at least one aperture. The bottom section of the substrate holder may be arranged within the holding member such that the growth substrate comprised therein be aligned with other growth substrates comprised in adjacently arranged substrate holders along the second axis. The present embodiment is further advantageous in that the at least one aperture enables nutrient solution to reach the growth substrate comprised in the substrate holder directly, i.e. without interference. It will thus be appreciated that the at least one aperture of the substrate holder be aligned with the flow of dripping of nutrient solution via the first, second and/or third path of the passage provided by the hollow body. It is to be noted that an arrangement according to the present embodiment does not require a second protrusion pattern arranged within the holding members as such pattern may instead be arranged on the substrate holder directly. The substrate holder may therefore fulfil the function established for the second protrusion pattern. It will further be appreciated that the function fulfilled by the flange portion mentioned in a previous embodiment may be fulfilled by the second protrusion pattern arranged on the substrate holder as the flange portion of the holding member may be encumbered by the presence of the substrate holder through the respective openings of the holding members.

Further objectives of, features of, and advantages with, the present invention will become apparent when studying the following detailed disclosure, the drawings and the appended claims. Those skilled in the art will realize that different features of the present invention can be combined to create embodiments other than those described in the following. BRIEF DESCRIPTION OF THE DRAWINGS

This and other aspects of the present invention will now be described in more detail, with reference to the appended drawings showing embodiment s) of the invention.

Figs la, lb and lc schematically show different models of the structure for hydroponic cultivation exemplifying the embodiments of the present invention,

Fig. 2 schematically shows a section view of a first structure for hydroponic cultivation according to an exemplifying embodiment of the present invention,

Fig. 3 schematically shows a section view of a second structure for hydroponic cultivation according to an exemplifying embodiment of the present invention,

Figs. 4a and 4b schematically show the second and third path of the passage of the hollow body of a structure for hydroponic cultivation according to an exemplifying embodiment of the present invention,

Fig. 5 schematically shows the positioning of a growth substrate within a structure for hydroponic cultivation according to an exemplifying embodiment of the present invention, and

Fig. 6 schematically shows an arrangement of structure for hydroponic cultivation according to exemplifying embodiments of the present invention.

DETAILED DESCRIPTION

Fig. la, Fig. lb and Fig. lc respectively illustrate alternative models of a structure 101, 102, 103 for hydroponic cultivation according to exemplifying embodiments of the present invention. It will be appreciated that the three structures 101, 102, 103 as exemplified in Fig. la, Fig. lb and Fig. lc are not exhaustive and that other structures are possible.

Fig. la shows a structure 101 for hydroponic cultivation having a hollow body 110 and a plurality of holding members 120 arranged on one side of the structure 101 along an axis parallel to the central axis of the hollow body 110. The plurality of holding members 120 is further shown in Fig. la integrally formed with the hollow body 110 such that the complete structure 101 may be manufactured by blow molding techniques preventing critical stress concentration areas to form at the juncture between the holding members 120 and the hollow body 110. Fig. la further illustrates openings 130 of the hollow body 110 concentrically aligned with the central axis of each holding member 120 (discussed in more detail later in Fig. 2 and 3). It will be appreciated that the respective opening 130 of the hollow body 110 may be also be understood as respective openings 130 of each holding member 120. A growth substrate and/or a substrate holder may be inserted into a holding member 120 via the openings 130. Plants or crops inserted into and/or arranged within the growth substrate may grow and extend out of the structure 101 via the openings 130 until harvesting is performed. The distancing 140 shown between subsequent holding members 120 in Fig. la may preferably be ranging from 5 cm to 20 cm, more preferably 7 cm to 15 cm, and most preferred 8 cm to 10 cm. The distancing 140 further depends on the type of crops grown in the structure 101 pertaining to the different growth sizes extending out of the structure 110 through the openings 130. It will be appreciated that the number of holding members 120 arranged on the hollow body 110 may be selected as a function of the length or height of the structure 110 and/or the distancing 140 between each holding member 120.

Fig. lb illustrates a structure 102 for hydroponic cultivation comprising similar features and characteristics as the structure 101 of Fig. la. The structure 102 differs from the structure 101 in that the plurality of holding members 120 are arranged along two axes parallel to the central axis of the hollow body 110. In other words, the plurality of holding members 120 is arranged on both sides of the hollow body 110 of structure 102, resulting in an increase in cultivation capacity. Fig. lb further illustrates a slightly different geometry of openings 130 and holding members 120 in contrast to Fig. la, which will be discussed in further detail in Fig. 3. Compared to the structure 101 of Fig. la, the structure 102 as exemplified in Fig. lb shows a hollow body 110 with a larger dimension to accommodate a greater number of growth substrates as the holding members 120 are located on both sides. It will be appreciated that the dimension of the hollow bodies 110 for Figs la, lb and lc may also be dependent on the types of plants or crops grown in respective structures 101, 102 and 103 and dependent on the number of holding members 120 arranged thereon.

Fig. lc illustrates another exemplifying structure 103 for hydroponic cultivation having a plurality of holding members 120 arranged along an axis parallel to the central axis of the hollow body 110. The holding members 120 shown in Fig. lc comprise another possible geometry which is not designed for any particular manufacturing method.

Fig. lc further shares the characteristics of the structures 101, 102 described in Fig. la and Fig. lb, respectively, pertaining to the openings 130 and the distancing 140 between the holding members 120.

Fig. 2 schematically shows a structure 200 for hydroponic cultivation similar to the structure 103 presented in Fig. lc. The structure 200 as exemplified in Fig. 2 further shows a hollow body 210 elongating along a first axis A. The structure 200 also comprises a plurality of holding members 220 arranged along a second axis, B, parallel to the first axis, A, and comprising at least one holding member 221, 222. Each holding member 221, 222 of the plurality of holding members 220 is shown in Fig. 2 elongating along a third axis, C. The third axis, C, in turn forms an angle, a, with the first axis, A. The holding members 221, 222 are arranged to receive and/or hold a respective growth substrate (not shown) via their respective openings 230. It will be appreciated that the third axis, C, along which each holding member 221, 222 of the plurality of holding members 220 elongates, forms the same angle, a, with the first axis, A, of the hollow body 210. The angle, a, may preferably be ranging from 15° to 75°, preferably from 20° to 70° and most preferably from 35° to 45°. Moreover, Fig. 2 further illustrates a first protrusion pattern 250 comprising at least one protrusion 251 which is shown protruding inwardly i.e. in the direction of the centre of the hollow body 210.

The protrusion(s) 251 of the first protrusion pattern 250 is (are) further depicted as comprising a curvature starting from the centre of the inner wall of the hollow body 210 and directed towards a passage 240 and towards each holding member 221, 222. It will be appreciated that the at least one protrusion 251 arranged in the passage 240 and protruding inwardly toward the center of the hollow body 210 may also be understood as protruding toward the first axis, A.

The passage 240 is represented in Fig. 2 as the passage, path or corridor between two subsequently arranged holding members 221, 222 aligned with the dripping output of each protrusion 251 of the first protrusion pattern 250 and aligned with the second axis, B. Moreover, the structure 200 of Fig. 2 shows a second protrusion pattern 280 comprising at least one protrusion 281. The protrusion(s) 281 of the second protrusion pattern 280 is shown protruding inwardly i.e. in the direction of the centre of its relative holding member 221, 222. The protrusion(s) 281 of the second protrusion pattern 280 is(are) shown elongating along the length of each holding member 221, 222 such that the growth substrates (not shown) may be held securely within each holding member 221, 222. Fig. 2 further shows the thickness of the protrusion(s) 281 of the second protrusion pattern 280 being minimal in order to decrease the contact surface between said protrusion(s) and the growth substrates.

The second protrusion pattern 280 is further shown aligned perpendicularly to the respective openings 230 of the holding members 221, 222. Moreover, the dimensions of the openings 230 are limited by the flange portion 260 and the rim 270 comprised on each holding member 221, 222 of the plurality of holding members 220. The flange portion 260 is shown in the passage 240 of Fig. 2 and creates a point in the structure 200 where the nutrient solution released from the growth substrate held by holding member 221 may accumulate to then drip onto the growth substrate held by holding member 222 (discussed in more detail in Fig. 4). Fig. 2 thus illustrates the rim 270 as a folded section of the holding member 221, 222 in the direction of its centre such that it prevents splatter of nutrient solution from exiting the structure 200 but does not incumber the growth of the crops.

Fig. 3 schematically shows a structure 300 for hydroponic cultivation similar to the structure 102 presented in Fig. lb. Fig. 3 further shows a hollow body 310 elongating along a first axis, A, and a plurality of holding members 320 arranged along second axes, B, on both sides of the hollow body 310 and parallel to the first axis, A. The plurality of holding members 320 comprises two holding members 321, 322 according to this example, shown integrally formed with the hollow body 310. Fig. 3 further illustrates each holding member 321, 322 of the plurality of holding members 320 elongating along a third axis, C, which in turn forms an angle a with the first axis, A. Analogously with the previous exemplifying embodiments, the holding members 321, 322 are arranged to each receive and/or hold a growth substrate 390 via their respective openings 330. It will be appreciated that the respective third axis, C, along which each holding member 321, 322 of the plurality of holding members 320 elongates, forms the same angle, a, with the first axis, A, of the hollow body 310. The angle, a, may preferably be ranging from 15° to 75°, preferably from 20° to 70° and most preferably from 35° to 45°. It will further be appreciated that each growth substrate 390 is completely inserted within the holding member 321, 322 of the plurality of holding members 320. Moreover, Fig. 3 further illustrates a first protrusion pattern 350 comprising at least one protrusion 351 which is shown protruding inwardly i.e. in the direction of the centre of the hollow body 310. It will be appreciated that the structure 300 presented in Fig. 3 is symmetrical about the first axis, A, e.g. the first protrusion pattern 350 is shown on both sides of the first axis, A, in the hollow body 310. The protrusion(s) 351 of the first protrusion pattern 350 is (are) further depicted as comprising a curvature starting from the centre of the inner wall of the hollow body 310 and directed towards a passage 340 and towards each holding member 321, 322. The passage 340 is represented in Fig. 3 as the passage, path or corridor between two subsequently arranged holding members 321, 322. The passage 340 is aligned with the dripping output of each protrusion 351 of the first protrusion pattern 350, and is (at least substantially) aligned with the second axis, B. Fig. 3 further illustrates a first path 341 of the passage 340 via which a flow of droplets 395 of nutrient solution are redirected by the first protrusion pattern 350 from the inner walls of the hollow body 310 towards a holding member 321, 322 and from a first holding member 321 to a adjacently arrange holding member 322. Moreover, the structure 300 of Fig. 3 shows a second protrusion pattern 380 comprising at least one protrusion 381. The protrusion(s) 381 of the second protrusion pattern 380 is (are) shown protruding inwardly i.e. in the direction of the centre of its relative holding member 321, 322. The protrusion(s) 381 of the second protrusion pattern 380 is (are) shown elongating along the length of each holding member 321, 322 such that the growth substrates 390 are held securely within each holding member 321, 322. Fig. 3 further shows the thickness of the protrusion(s) 381 of the second protrusion pattern 380 being minimal in order to decrease the contact surface between said protrusion(s) 381 and the growth substrates 390. The second protrusion pattern 380 is further shown aligned perpendicularly to the openings 330. Moreover, the dimensions of the openings 330 are limited by the flange portion 360 and the rim 370 comprised on each holding member 321,

322 of the plurality of holding members 320. The flange portion 360 is shown in the passage 340 of Fig. 3 and creates a point in the structure 300 where the nutrient solution released from the growth substrate held by holding member 321 may accumulate to then drip onto the growth substrate held by holding member 322 (discussed in more details in Fig. 4). Fig. 3 thus illustrates the rim 370 as a folded section of the holding member 321, 322 in the direction of its centre such that it prevents splatter of nutrient solution from exiting the structure 300 but does not incumber the growth of the crops.

Fig. 4a and Fig. 4b schematically show a structure 400 for hydroponic cultivation in which a flow of droplets 495 travels or progresses from a first holding member

421 to a second holding member 422 via the second and third paths 441, 442, respectively, of a passage 440 of the hollow body 410. Fig. 4a shows the structure 400 comprising a hollow body 410 and a plurality of holding members 421, 422 having the same technical characteristics as explained in relation to Fig. 2 and Fig. 3 above. Fig. 4a further illustrates growth substrates 491, 492 inserted through the openings 430 into each holding member 421,

422 and held by the second protrusion pattern 480. The growth substrates 491, 492 are positioned in the holding members 421, 422 in the direction of the second axis of said holding members 421, 422 such that the lowest point of the growth substrate 491 held by the holding member 421 is aligned with the surface of the growth substrate 492 held by the adjacently arranged holding member 422 without interference. Fig. 4a further shows the flow of droplets 495 being released from the growth substrate 491 held by the holding member 421 and dripping directly onto the growth substrate 492 held in the holding member 422 along the second path 441 of the passage 440, without any interference from obstacles and without contacting the inner wall surface of the hollow body 410. It will be appreciated that the progression of the nutrient solution through the growth substrate 491, 492 is governed by adhesion of said nutrient solution or water to the growth substrate 491, 492 and cohesion within the nutrient solution and progresses through the growth substrate 491, 492 under the effect of gravity. It will further be appreciated that the direct dripping of the flow of droplets 495 via the second path 441 of the passage 440 is similar between each adjacently arranged holding members of the plurality of holding members. Moreover, the growth substrates 491, 492 illustrated in Fig. 4a are shown having a cylindrical geometry elongated in the same direction as the holding members 421, 422 allowing the root system (not shown) of a plant or crop to grow with sufficient space within the holding members 421, 422 and allowing the root system 450 of the plant or crop to extent out from the holding members 421, 422 via the openings 230. Furthermore, Fig. 4b also illustrates the structure 400 as shown in Fig. 4a comprising similar features and characteristics. Fig. 4b however shows the flow of droplets 495 being released from the growth substrate 491 held by the holding member 421 dripping indirectly onto the growth substrate 492 held in the holding member 422 along a third path 442 of the passage 440. A flange portion 460 is arranged in the third path 442 of the passage 440 shown in Fig. 4b. This generates a concentration point in the geometry of the holding member 421 such that any droplets 495 of nutrient solution released on the inner wall of the holding member 421 accumulate at the flange portion 460 and detaches therefrom to drip onto the growth substrate 492 held by the adjacently arranged holding member 422. It is to be noted also that a flow of nutrient solution may travel or progress from one holding member to the adjacently arranged holding member via any of the first, second and/or third path of the passage defined above in relation to Fig. 2-Figs. 4a-b.

Fig. 5 shows a structure 500 for hydroponic cultivation similar to the structure 300 shown in Fig. 3. The structure 500 comprises a hollow body 510 and a plurality of holding members 520 integrally formed with the hollow body 510 and positioned on both sides of said hollow body 510. Fig. 5 further illustrates another perspective view of a flange portion 560 and rim 570 determining the dimensions and geometry of the opening 530 of each of the holding member of the plurality of holding members 520. The opening 530 in Fig. 5 is shown having a non-circular geometry wherein the flange portion 560 prolongs in the direction of the centre of the opening 530 such that said flange portion 560 enables detachment of the flow of droplets of nutrient solution over the surface of the growth substrate 590 held within the holding member of the plurality holding members 520. Fig. 5 further depicts a mid-section view a holding member 521 of the plurality of holding members 520 in which a growth substrate 590 is held by the at least one protrusion of the second protrusion pattern 580. The protrusions of the second protrusion pattern 580 are shown protruding inwardly towards the centre of the holding member 521 such that the contact surface 540 between the protrusions and the growth substrate 590 is minimal. Fig. 5 shows said contact surface 540 being represented by the longitudinal edge of each protrusion of the second protrusion pattern 580 elongating along the second axis, i.e. central axis, of the holding member 521. The restricted contact surface 540 allows the growth substrate 590 to be securely wedged within the holding member 521 and allows the root system 591 of the plant or crop to grow radially and axially without obstruction from the structure 500 and with sufficient space for aeration. Furthermore, the growth substrate 590 is shown in Fig. 5 having a cylindrical form elongated along the axis of the holding member 521 and comprising a central channel 592 allowing seed(s) to be inserted into the growth substrate 590. It will be appreciated that the central channel 592 may only partially extend through the growth substrate 590 thus preventing the seed(s) from falling from the growth substrate 590. Moreover, the central channel 592 may be pre-formed when the growth substrate 590 is manufactured or it may be formed by the seeding machinery when the seed(s) is/are planted.

It will be appreciated that the central channel 592 further provides advantageous aeration to the growth substrate 590. It will further be appreciated that the growth substrate 590 may take alternatives geometries to the one recited above provided it comprises similar characteristics pertaining to its positioning in the holding members of the plurality of holding members 520 and to the growth of the crops.

Fig. 6 schematically shows an arrangement 600 for hydroponic cultivation comprising at least one structure 601 according to one or more of the exemplifying embodiments of the present invention. Furthermore, Fig. 6 shows the structure 601 comprising a hollow body 610 and plurality of holding members 620 arranged on both sides of the hollow body 610 and having the same technical characteristics as explained in relation to Figs. 2-5 above. Fig. 6 further shows the structure 601 of the arrangement 600 comprising a plurality of substrate holders 615 inserted into each holding member of the plurality of holding members 620. The substrate holders 615 are represented in Fig. 6 as receptacles or containers within which growth substrates 690 are inserted and held in position. Fig. 6 further shows the substrate holders 615 comprising an upper section 630 and a bottom section 650. The upper section 630 extends out from the holding member of the plurality of holding members 620 and the bottom section 650 is comprised within said holding member of the plurality of holding members 620. The upper section 630 shown in Fig. 6 comprises a uniform surface with sufficient length such that it facilitates automation of the cultivation of crops in the arrangement 600 of structures 601. The upper section 630 further comprises dimensions, slightly larger than the opening of the holding member such that an abutment surface 671 abuts the rim 670 and the flange portion 672 of the holding member thus securely immobilizing the substrate holder 615 in said holding member. The bottom section 650 of the substrate holder 615 is further shown in Fig. 6 comprising at least one aperture 695 such that the growth substrate 690 held within the substrate holder 615 is at least partly exposed and capable of receiving a flow of droplets 641 of nutrient solution dripping from an adjacently arranged substrate holder. Fig. 6 further shows the bottom section 650 of the substrate holder 615 comprising a plurality of fins 680 holding in place the growth substrate 690 and providing a low point 660 from which droplets 641 of nutrient solution released from the growth substrate 690 may accumulate and detach to travel or progress towards an adjacently arranged holding member, holding a subsequent substrate holder, via the passage 640 provided by the hollow body 610. Fig. 6 therefore illustrates the at least one fin 680 of each substrate holder 615 fulfilling the function of the second protrusion pattern described in relation to Fig. 2-5.

The person skilled in the art realizes that the present invention by no means is limited to the preferred embodiments described above. On the contrary, many modifications and variations are possible within the scope of the appended claims. For example, the structures, the holding members, the first and second protrusion patterns, etc. may encompass alternative geometries provided that they fulfil the functions described above.

Claims

1. A structure (101, 102, 103, 200, 300, 400, 500, 601) for hydroponic cultivation, comprising a hollow body (110, 210, 310, 410, 510, 610) elongating along a first axis, A, a plurality of holding members (120, 220, 320, 420, 520, 620) integrally formed with the hollow body and arranged along at least one second axis, B, parallel to the first axis, A, wherein each holding member is arranged to hold a growth substrate (390, 491, 492, 590, 690) via a respective opening (130, 230, 330, 430, 530) of each holding member, wherein the hollow body provides a passage (240, 340, 440, 640) arranged along the second axis, B, and between the plurality of holding members, such that, in a vertical arrangement of the structure, droplets (395, 495, 641) released from a first holding member (221, 321, 421, 521) of the plurality of holding members are arranged to drip in the passage towards a second holding member (222, 322, 422, 522) of the plurality of holding members, adjacently arranged below the first holding member.

2. The structure according to claim 1, wherein each holding member elongates along a third axis, C, forming an angle, a, with the first axis, A.

3. The structure according to claim 2, wherein the angle, a, is in the range of 15°- 75°, preferably 30°-70° and most preferred 35°- 45°.

4. The structure according to any one of the preceding claims, further comprising a first protrusion pattern (250, 350) comprising at least one protrusion (251, 351) arranged in the passage and protruding inwardly toward the first axis, A, such that, in a vertical arrangement of the structure, the first protrusion pattern is arranged to direct droplets, released from the first holding member, towards the second holding member, in a first path (341) of the passage.

5. The structure according to claim 4, wherein droplets released from the first holding member are arranged to drip onto the growth substrate, held by the second holding member, via the first protrusion pattern.

6. The structure according to any one of the preceding claims, wherein, in a vertical arrangement of the structure, droplets released from the first holding member are arranged to drip directly onto the growth substrate, held by the second holding member, in a second path (441) of the passage.

7. The structure according to any one of the preceding claims, wherein a first holding member of the plurality of holding members, adjacently arranged to a second holding member of the plurality of holding members, comprises a flange portion (260, 360, 460, 560, 672) arranged in the passage and adjacently the opening of the second holding member, such that, in a vertical arrangement of the structure, droplets released from the first holding member are arranged to drip towards the second holding member, in a third path (442) of the passage.

8. The structure according to any of the preceding claims, wherein each holding member further comprises a second protrusion pattern (280, 380, 480, 580) comprising at least one protrusion (281, 381) protruding inwardly toward the centre of the holding member, wherein the second protrusion pattern is arranged to hold the growth substrate.

9. The structure according to any of the preceding claims, wherein the respective opening of the hollow body comprises a rim (270, 370, 570, 670) such that each holding member is arranged to receive and to hold a substrate holder (615) comprising a growth substrate.

10. The structure according to any of the preceding claims, comprising a hydrophobic material.

11. An arrangement (600) for hydroponic cultivation, comprising at least one structure according to any of the preceding claims, a plurality of growth substrates, wherein each holding member of the at least one structure is arranged to hold a respective growth substrate of the plurality of growth substrates.

12. The arrangement according to claim 11, wherein each growth substrate is arranged in a substrate holder, and wherein each holding member is arranged to hold the respective growth substrate via the substrate holder.

13. The arrangement according to claim 12, wherein the substrate holder comprises a bottom section which comprises at least one aperture (695).