Vertical Farm

Abstract

The invention relates to a vertical farm with cultivation units (1) comprising a lighting system. The lighting system comprises at least one module (2) for collecting a total output of incident daylight (3) and has an arrangement for distributing (4) the total output in partial outputs to the cultivation units (1).

Description

[0001] The invention relates to a vertical farm with culture units having a lighting system.

[0002] Vertical farming is a relatively new technology. In 1964, a 41-meter-high tower greenhouse designed by inventor and mechanical engineer Othmar Ruthner was exhibited at the International Garden Show in Vienna. Subsequently, more tower greenhouses were built: in 1965, a 23-meter-high tower was built in the research garden of Bayer-Werke AG in Leverkusen; in the same year, the 18-meter-high tower was built by nursery owner Ernst Haller in Rüfenach, Switzerland; and finally, a 54-meter-high tower was built in Chorzów, Poland. Othmar Ruthner obtained patent AT243553B for his "greenhouse with a tower-like structure" in 1963. None of these buildings exist today. The reasons why vertical farming was unable to establish itself alongside conventional, open-air, horizontal farming at this early stage were the high costs of building construction, high energy costs, and structural problems.The tower in Chorzow was taken out of service due to the reduction in light transmittance of the polyester outer skin.

[0003] However, the basic idea of vertical farming remains, as it offers numerous advantages over conventional open-air farming. Vertical farming enables very high productivity relative to the area cultivated.

[0004] In addition, this cultivation technique is significantly more cost-effective than conventional open-field plant cultivation. The reasons for this are manifold. These include, for example, the significantly reduced water requirement, the ability to precisely adjust the dosage of plant nutrients to the plant's needs, the significantly reduced use of pesticides, some of which can even be completely eliminated, the reduction in transport distances, and the largely independent dependence on weather conditions, to name just the most important factors.

[0005] These advantages not only make vertical farming economically attractive, they also contribute to reducing environmental impact and helping to meet the ever-increasing demand for food.

[0006] As a result, there are now companies operating farms in the form of vertical agriculture. Many of the problems that affected the original tower greenhouses have been eliminated through new concepts and technologies. For example, current detailed solutions for use in the controlled environment of vertical plant production are disclosed in EP 3 768 071 B1 and WO 2019 / 183244.

[0007] The ambitious concept of a "tower-like structure" was largely abandoned because the towers' enormous height would have caused very unfavorable temperature and humidity distributions. In addition to reducing building height and the associated expansion of the floor space, modern farm buildings generally also dispense with a transparent outer shell made of glass or transparent plastics. This primarily counteracts excessive heating of the farm buildings and prevents overheating and radiation damage to the plants.

[0008] Furthermore, an outer skin made of glass or plastic offers insufficient insulation in colder outside temperatures, so that heating is costly under these conditions.

[0009] However, the construction of a vertical farm as a predominantly closed building without direct access to daylight means that the crops must be artificially illuminated.

[0010] This results in certain advantages for plant cultivation, as the artificially generated light can be very precisely adapted to the needs of the plants in terms of both quantity and spectral composition.

[0011] The main disadvantage of these artificial lighting systems, however, is the very high energy costs associated with supplying the plants entirely with artificial light. Despite the low energy requirements of LED lights and the narrowing of the emitted light to the photosynthetically active parts of the spectrum, the costs of artificial lighting are so high that the systems are often marginally economical to operate. The use of photovoltaic systems to reduce energy costs is often not possible due to limited space capacity. Furthermore, the efficiency of such systems is relatively low, and the investment costs are very high.

[0012] Currently, tomatoes, lettuce, and herbs are mostly cultivated in vertical farms, as these crops thrive particularly well under the conditions of vertical cultivation in enclosed spaces, can survive with relatively little light, and can be marketed with good margins.

[0013] Crucial to the future food security of a constantly growing population are crops from the grass family (Poaceae / Gramineae), such as corn, rice, and wheat. However, these species from this important family of crops require significantly more light for growth. Currently, they are not cultivated in vertical farms with exclusively artificial lighting.

[0014] The object of the invention is to provide a vertical farm that excels, particularly in terms of energy efficiency and productivity in crop production. The innovative vertical farm is intended to be characterized by low energy consumption and contribute to more sustainable agricultural practices. At the same time, high production output is to be ensured and harvest efficiency increased. The vertical farm according to the invention is intended to contribute to resource conservation. The invention is intended to be characterized by environmental friendliness while simultaneously optimizing the use of existing resources. The invention is intended to be applicable for the cultivation of a wide variety of plant species.

[0015] This object is achieved according to the invention with a vertical farm according to the main claim and a subordinate use claim. Preferred variants and features can be found in the subclaims, the description, and the drawings.

[0016] Measurements have shown that by using modules to collect a total amount of daylight and a system for distributing the total amount of light into partial amounts among crop units, it is possible to provide a cultivation area of approximately 60 square meters with a sufficient amount of light in direct sunlight, which in Central Europe amounts to approximately 550,000 Ix at midday on summer days. This area value is derived from the fact that plants require approximately 2,000-10,000 Ix for healthy growth.

[0017] Naturally, this optimal value decreases depending on the season, the prevailing weather conditions, and the requirements of the crops being cultivated. Therefore, the precise location factors for each system must be determined individually for the specific design of a vertical farm that operates predominantly with daylight.

[0018] In a preferred embodiment, the modules are arranged on the roof and / or on the side walls of the vertical farm.

[0019] Starting from these modules, an array of light-guiding elements must be set up to guide the collected daylight in the enclosed cultivation space of the vertical farm to the cultivation units. In a preferred embodiment, these light-guiding elements consist of a light-guiding tube and / or a light-guiding fiber bundle.

[0020] Prismatic elements are arranged to spectrally distribute the collected daylight.

[0021] Alternatively or additionally, spectrally selective optical filters, which function as beam splitters, for example, can also be used.

[0022] Coated mirrors that reflect spectrally selectively or optical gratings can also be used.

[0023] Thanks to these devices, the separated spectral components can be used for different purposes.

[0024] Reflective elements are required to direct the collected daylight in a desired direction and / or to focus it more strongly. In a preferred design, these reflective elements are designed as concave mirrors.

[0025] An arrangement for regulating the distribution of the collected daylight ensures a homogeneous distribution of the amount of daylight in the horizontal and vertical extent of the cultivation levels.

[0026] In a preferred embodiment, this control can be achieved via the cross-sections of the light guide elements. Control is achieved by using suitable sensors to detect the outcoupled light and suitable actuators to adjust the distributed and penetrated light.

[0027] The portions of the energy from the coupled daylight that are selectively separated by the above-mentioned elements for spectral splitting of the daylight can be converted into electrical energy by arranging downstream photovoltaic cells. The electrical energy thus generated can be used to directly power the elements for generating artificial light, preferably LEDs. Alternatively, the electrical energy can also be stored in a suitable medium. This energy serves as a buffer to bridge periods of low daylight or to bridge the darkness at night. In a preferred embodiment, this energy storage device consists of a lithium iron phosphate battery.

[0028] Furthermore, the specified lighting system is configured to include elements for generating artificial light. This artificial light is generated in the physiological quantity and quality required for photosynthesis either in close proximity to the culture units and / or guided to the culture units via an array of light-guiding elements. This artificial light, preferably generated via LEDs, is either guided to the cultures via fiber optic bundles or generated directly above the cultures.

[0029] The spectral adjustment of daylight and / or the light generated by the elements used to generate artificial light is achieved by arranging a control device. This control device stores not only the optimal spectral composition of the light to be coupled out, but also the optimal exposure times and exposure doses, tailored to the respective cultivated crop species.

[0030] The devices described in the preceding description ensure that the total power of the collected daylight is divided into partial powers in equal parts.

[0031] This quantitative, homogeneous distribution is necessary because the cultivation areas of the cultivation units each have the same area. This allocation is essential in order to be able to functionally dimension the specific design of the lighting system of a vertical farm according to its geographical location.

[0032] In order to exclude the negative influences of direct daylight, e.g. through transparent glass or plastic surfaces, it is necessary that the roof and side walls of a vertical farming system

[0033] suitable building are largely opaque. In a preferred embodiment, the roof and walls are constructed using standard elements for sandwich systems established in hall construction. The modules for collecting a total amount of incident daylight are integrated into these elements. Further features and advantages of the invention can be found in the accompanying figures. List of reference symbols 1 cultural units 2 Module 3 Daylight 4 Order for distribution 5 light guide elements 6 prismatic elements 7 reflective elements 8 Device for regulating distribution 9 Device for converting and storing daylight energy 10 elements for generating artificial light 11 Control device 12 opaque roof 13 opaque walls (13) 14 coupled daylight 14a optical fiber with coupled daylight 15 distributed daylight 15a light-conducting fiber with distributed daylight 16 penetrated daylight 16a optical fiber with continued daylight 17 extracted daylight 18 vertical light-guiding tube 19 horizontal light-conducting tube 20 partially transparent mirrors 21 partially transparent material 22 bundles of optical fibers 23 collector concave mirrors 24 deflecting concave mirrors 25 red and blue parts of daylight for plant illumination 26 green part of daylight 27 beam splitter (filter) permeable to green light 28 beam splitter (filter) permeable to red and blue light 29 photovoltaic cells 30 incident light 31 reflected light 32 partially translucent material 33 scattering partially translucent material 34 skylight dome

[0034] Fig. Figure 1 schematically shows a vertical farm with a lighting system according to the invention. In the illustrated embodiment, the incident daylight 3 is collected by the modules 2 mounted on the opaque side wall 13 and / or on the opaque roof 12.

[0035] Daylight 3 is guided by the light-guiding elements 5 to the cultivation units 1. The light-guiding elements 5 can be designed, for example, as a light pipe and / or as a fiber optic bundle. In the illustrated embodiments, both natural light and natural light that has been spectrally modified, or artificially generated light, can be guided throughout the entire lighting system. A distribution arrangement 4 determines how the total power of incident daylight 3 is divided into the partial powers to be distributed.

[0036] Using prismatic elements 6 and / or reflective elements 7, the spectral composition of the light can be varied according to the needs of the crop being cultivated. A distribution control device 8 and a control device 11 determine which partial powers of the incident light in which ranges of the spectrum are guided via the further light-guiding elements 5 to the cultivation units 1, and which partial powers or which spectral ranges of daylight 3 flow into the device 9 for converting and storing daylight energy. The energy stored in this device 9 can be converted back into artificial light in the elements for generating artificial light 10 during times of insufficient daylight or at night, with its spectral composition specifically tailored to the respective crop.

[0037] Fig. Figure 2 shows a preferred embodiment of the light-guiding elements 5 of the lighting system as a light-guiding tube system. The coupled daylight 14 is transmitted vertically via a vertical light-guiding tube 18. At the height of the respective cultivation levels of the vertical farm, the coupled daylight 14 or the penetrated daylight 16 is divided via semi-transparent mirrors 20. At each level of the tube system, the distributed daylight 15 is guided into the horizontal light-guiding tubes 19. The distributed daylight 15 is distributed homogeneously across the cultivation units on all levels of the vertical farm as decoupled daylight 17 via a surface made of semi-transparent material 21.

[0038] Fig. Figure 3 shows a preferred embodiment of the light-guiding elements 5 of the lighting system in the form of light-guiding fiber bundles. The coupled-in daylight 14 is transmitted vertically via bundles of light-guiding fibers (22). At the height of the respective cultivation level of the vertical farm, individual fibers branch off from the bundles of light-guiding fibers (22) as light-guiding fibers with distributed daylight 15a. The remaining light-guiding fibers with coupled-in daylight 14a continue downwards as light-guiding fibers with further daylight 16a to the next distribution level. The daylight 17 is coupled out directly via the ends of the light-guiding fibers with further daylight 15a.

[0039] The Fig. 4a, Fig. 4b and Fig. 4c show preferred designs of modules 2 in their function as coupling structures. Fig. 4a and Fig. 4b shows modules 2, which capture the daylight 3 incident from different directions through collector concave mirrors 23 and project it onto a deflecting concave mirror 24. The deflecting concave mirror 24 then directs a concentrated light beam through an opening at the lower pole of the collector mirror 23 into a vertical light-conducting tube 18 ( Fig. 4a) or alternatively to a bundle of optical fibers 22 ( Fig. 4b).

[0040] In a further embodiment, the collector concave mirror 23 and the deflecting concave mirror 24 connected to it are configured so that their orientation can be adjusted by suitable devices. This makes them suitable for following the daily course of the sun's trajectory. Furthermore, their positioning can be adapted to the seasonal variations in the position of the sun.

[0041] Fig. 4c shows an alternative embodiment of modules 2 as skylights 34.

[0042] Due to their curvature, the skylight domes 34 are able to absorb the daylight 3 and direct it in a focused manner into a vertical light-guiding tube 18 or, alternatively, onto a bundle of light-guiding fibers 22. The geometry of the dome shape of the skylight domes 34 can be adapted to the geographical conditions at the location of the vertical farm. The coupling of the daylight 3 into the various design variants of the light-guiding elements 5 is freely selectable. The representation in Fig. 4c is exemplary.

[0043] In a further variant, the modules (2) for collecting daylight can also be designed in the form of Fresnel lenses.

[0044] The Fig. 5a and Fig. 5b shows two preferred embodiments for the spectral division and use of daylight.

[0045] In Fig. 5a, an incident light beam 30 strikes a beam splitter 26 that is transparent to the green components of daylight. This portion of the daylight spectrum, which has only a minimal photosynthetic effect, then strikes a photovoltaic cell 29, where it is converted into electrical energy. This electrical energy can then be stored in a suitable medium as needed, or it can be used directly to generate artificial light, preferably via LEDs that emit in the blue and red spectral range. The red and blue components of daylight 25 are used directly to illuminate the plants.

[0046] An alternative design variant shows Fig. 5b. Here, an incident light beam 30 strikes a beam splitter 28 which is transparent to red and blue light. The green portion of the daylight 26, which has only a slight photosynthetic effect, is reflected and reaches a photovoltaic cell 29. According to the design variant in Fig. 4a, the electrical energy is then stored in a suitable medium as needed, or it is used directly to power LEDs. Accordingly, in this embodiment, the red and blue components of daylight are also used to illuminate the plants 25.

[0047] The Fig. 6a and Fig. 6b shows two different coupling variants of the fiber optic system.

[0048] In Fig. 6a, an incident light beam 30 reaches a partially transparent material 32. As a result, the outcoupled light reaches the culture plane in a more concentrated manner. In Fig.6a, an incident light beam 30 hits a partially transparent material 33 with scattering elements. This diffuses the outcoupled light to the culture plane. This arrangement is particularly suitable for light emerging directly from the ends of glass fibers. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] AT 243553

[0002] EP 3 768 071 B1

[0006] WO 2019 / 183244

[0006]

Claims

[1] Vertical farm with culture units (1), characterized by that the vertical farm has a lighting system with at least one module (2) for collecting a total output of incident daylight (3) and an arrangement for distributing (4) the total output in partial outputs to the culture units (1). [2] Vertical farm according to claim 1, characterized by that the arrangement comprises light-guiding elements (5). [3] Vertical farm according to claim 1 or 2, characterized by that the arrangement comprises prismatic elements (6). [4] Vertical farm according to claim 1 to 3, characterized by that the arrangement comprises filters (27, 28). [5] Vertical farm according to claim 1 to 4, characterized by that the arrangement comprises coated mirrors (20). [6] Vertical farm according to one of claims 1 to 5, characterized by that the arrangement comprises reflective elements (7). [7] Vertical farm according to one of claims 1 to 6, characterized bythat the arrangement comprises a device (8) for controlling the distribution via sensors and actuators. [8] Vertical farm according to one of claims 1 to 7, characterized by that the arrangement has a device (9) for converting and storing energy from daylight. [9] Vertical farm according to one of claims 1 to 8, characterized by that the lighting system comprises elements (10) for generating artificial light. [10] Vertical farm according to one of claims 1 to 9, characterized by that the arrangement has a control device (11) for spectral adjustment of the daylight. [11] Vertical farm according to one of claims 1 to 10, characterized by that the total output is divided into partial outputs for each cultural unit (1) in equal parts. [12] Vertical farm according to one of claims 1 to 11, characterized by that the crop units (1) have the same cultivated areas. [13] Vertical farm according to one of claims 1 to 12, characterized by that daylight (5) only reaches the farm via the modules (2). [14] Use of a lighting system with at least one module (2) for collecting daylight (5) and an arrangement for distributing the daylight (5) in a vertical farm.

Images