Lighting device and lighting method for at least one

plant

The invention relates to a lighting device for at least one plant, with an artificial light unit for providing artificial light for illuminating the plant and with a sunlight unit for providing sunlight for illuminating the plant. The invention also relates to a corresponding method.

By 2050, 66% of the world's population will live in cities. That's more than 6 trillion people and counting. At the same time, 80% of the world's arable land is already in agricultural use. The sustainable security of the urban food supply with limited resources is becoming an increasing challenge - especially in densely populated cities with limited access to surrounding agricultural areas, which in future will also be in greater conflict with the goals of building areas. In addition, intensive cultivation practices, the massive use of chemicals and increasingly unfavorable climatic conditions are major problems for future food production.

Against this background, work is being done worldwide on innovative cultivation methods and technologies that address these problems and focus on embedding food production in the urban structure. A particularly promising approach is vertical farming, vertical plant production or management in one its system to the exclusion of abiotic environmental factors such as precipitation or temperature. Despite the decisive advantage of a maximum area yield under controlled, reproducible interior or indoor conditions, the high energy consumption and overall operating costs in particular currently prevent the technology from being used across the board. With an energy cost share of up to 80%, plant lighting is the biggest cost driver.

Accordingly, the task is to provide a lighting device for at least one, ie one or more plants, which can be used in an energy-saving manner in indoor farming.

This object is solved by the independent patent claims. Advantageous embodiments result from the dependent claims, the description and the figure.

One aspect relates to a lighting device for at least one plant, i.e. one or more plants, with an artificial light unit for providing artificial light for illuminating the plant(s) and with a sunlight unit for providing sunlight for illuminating the plant (n). The artificial light unit can be an adjustable artificial light unit, which can be adjusted in terms of the spectral distribution and/or the intensity of the artificial light that is provided or generated and can have, for example, light-emitting diodes (LEDs) as artificial light sources. The solar light unit can, for example, comprise a sunlight collector or the like.

The lighting device also includes a mixing unit for generating a mixed light from the artificial light and the sunlight, and a distribution unit for distributing the mixed light and illuminating the plant (s) with the distributed mixed light, and a setting or control unit for automatic mechanical adjustment (or regulation) of a property of the mixed light. The setting within the meaning of the invention can therefore include or be regulation or control. The adjustment can in particular be a dynamic adjustment, so that the property of the mixed light can be flexibly adapted to changing conditions, as will be explained further below. In particular, the setting can include setting at least one property of the artificial light and/or setting a property of the sunlight. The artificial light can be adjusted, for example, by adjusting, ie controlling or regulating, the artificial light unit, for example dimming. Sunlight can be set, for example, by setting, ie controlling or regulating, a filter unit as described below. The sunlight that is mixed with the artificial light in the mixing unit can also be filtered and thus modified sunlight.

This has the advantage that a specific use, in particular use that is specific to length of time and/or use of intensity, is made possible under controlled conditions in a closed room. Sunlight can thus be supplemented with artificial lighting to create a specific plant light mixture, or properties that are unfavorable for plant growth can be filtered out of the sunlight. The plant light mixture, i.e. the mixture of light with which the plant is illuminated, can therefore be adapted to the respective needs of the plant and thus improve growth. This can also be sensor-based, as described further below, which enables a particularly advantageous dynamic optimization of the mixed light on the plant. The additional artificial lighting not only saves significant costs in the energy sector, but also extends their service life through the optimized control of the lamps in the artificial lighting unit, which in the usual systems are light-emitting diodes operated at the performance limit. This also leads to reduced waste and thus conserves resources. Because the lighting device described does not place any further requirements on indoor farming, it can be used in the entire field of indoor farming and thus enable competitive regional food production.

The lighting device described thus overcomes the disadvantages of the sun-tight building envelope that has been customary in indoor farming to date, with the exclusive operation of energy-intensive artificial light. The structure described also enables the lighting device to be controlled in a closed control loop, which, for example, as described below, collects and forwards sunlight, optically filters the sunlight, mixes sunlight and artificial light, sensor-based control of the properties of the mixed light with light mixtures favorable for plant growth and the homogeneous distribution of the mixed light. Thus, by mixing sunlight and artificial light, optimized conditions for plant growth can be created in every growth phase, with energy consumption also being minimized.

In an advantageous embodiment, it is provided here that the adjustable (in particular controllable) property comprises a spectral distribution and/or an intensity. This has the advantage that the mixed light can be adapted to the biological conditions in a particularly simple and cost-effective manner.

Another advantageous embodiment provides that the adjusting unit is designed to dynamically adjust a property of the mixed light, in particular by adjusting the property of the sunlight and/or a property of the artificial light. This has the advantage of flexible adjustment of the lighting to conditions that change over the course of the day, for example, which can be caused by a growth cycle of the plant, an astronomical cycle or a meteorological influence.

In a particularly advantageous embodiment, it is provided that the adjusting unit is designed to adjust the property of the mixed light according to a stored regulation. Such a stored specification can also be referred to as a specified mixed light recipe, for example, and includes in particular a specified spectral distribution and/or a specified intensity of the light. The stored specification or recipe can also be understood or referred to as a (stored) setpoint specification. The stored rule can also include a change in the mixed light over time, for example in the form of functions that include a time profile of an intensity and/or spectral distribution that the mixed light should have. For example, growth phases in plants can be taken into account when lighting, or general preferences of the plant variety or plant species to be illuminated by the lighting device, which in turn results in improved plant growth or increased effectiveness of the lighting with minimized energy consumption.

It can be provided that the specification is based on a measured variable, in particular a time and/or season and/or a temperature and/or air humidity and/or soil moisture and/or a nutrient concentration and/or a plant variety and/or a plant species and/or plant constituents to be induced and/or a date. In this way, the lighting can be adjusted particularly precisely.

In a further particularly advantageous embodiment it is provided that the lighting device also has a sensor unit for detecting a spectral distribution and/or an intensity of the sunlight and/or the mixed light and/or the artificial light. In this case, the setting unit is designed to set or regulate the property of the mixed light as a function of the detected spectral distribution and/or the detected intensity. In a particularly advantageous manner, by comparing the detected spectral distribution and/or intensity with the stored specification, ie the specified mixture trecipe, it can be determined which spectral components have to be amplified and which spectral components have to be attenuated. The dynamic that may be required to generate an optimal lighting spectrum

See adjustment or modulation of the sunlight, for example by Fil sion using the filter unit described below, and / or the enrichment that may be required by the artificial light can be calculated by a corresponding optimization method. Since the spectral distribution and/or intensity can be detected efficiently and inexpensively by commercially available spectral sensors, the spectral analysis of the variable sunlight or the other lights can also be carried out efficiently and inexpensively.

Correspondingly, in a further advantageous embodiment, the lighting device also includes a filter unit that can be adjusted by the adjustment unit for optically filtering the sunlight and/or the mixed light and/or the artificial light. The optical filtering of the sunlight and/or the mixed light is particularly advantageous here, since their spectral components, in contrast to artificial light, cannot be generated arbitrarily. In this way, undesired components of the light, which may impair plant growth, can also be reduced in a simple manner, thereby improving the overall effectiveness of the lighting.

In another advantageous embodiment, it is provided that the distribution units comprise a plurality of lighting units, to which the mixed light is distributed homogeneously and which then emit the mixed light onto the plant(s). The lighting units are arranged one above the other, particularly when used as intended, that is to say, for example, when viewed in a gravitational field on earth. With this arrangement above one another, the vertical arrangement, a lot of space can be saved on the one hand, and on the other hand shading effects in the usual lighting units are very restrictive, so that the light reaching the plants is typically particularly uneven here. Therefore, the advantage of homogeneous lighting, which causes uniform growth of the different plants or parts of plants, is increased here.

Another aspect also relates to a plant cultivation system with a lighting device according to one or more of the embodiments described and with one or more of the following devices:

A temperature control device for setting a temperature for the plant(s) that can be illuminated by the lighting device; an air humidification device for setting a humidity level for the plant(s) that can be illuminated by the lighting device; a soil moistening device for adjusting a soil moisture for the plant(s) that can be illuminated by the lighting device; a fertilizing device for adjusting a nutrient concentration for the plant(s) that can be illuminated by the lighting device. This has the advantage that the plant growth is improved by the lighting device via a centralized or dependent, also interdependent control of the different control devices and the lighting is further increased in its efficiency.

An additional aspect also relates to a method for illuminating at least one plant, with the method steps of providing artificial light for illuminating the plant, providing sunlight for illuminating the plant; generating a mixed light from the artificial light and the sunlight; adjusting a property of the mixed light; and distributing the mixed light and illuminating the plant with the distributed mixed light.

Advantages and advantageous embodiments of the method here correspond to advantages and advantageous embodiments of the lighting device or the plant cultivation system.

The combinations of features mentioned above in the description, as well as the features and combinations of features mentioned below in the description of the figures and/or shown alone in the figure, can be used not only in the combination specified in each case, but also in other combinations without departing from the scope of the invention . The invention therefore also includes and discloses embodiments that are not explicitly shown and explained in the figure, but proceed and can be generated from the explained embodiments by means of separate combinations of features. Versions and combinations of features are also to be regarded as disclosed which therefore do not have all the features of an originally formulated independent or dependent claim. In addition, versions and combinations of features, in particular

special by the statements set out above, to be regarded as disclosed, which is beyond the in den back references of the claims set out combinations of features go beyond or deviate from these.

Embodiments of the invention will be explained in more detail with reference to a schematic drawing rule.

1 shows an exemplary embodiment of a lighting device for at least one plant.

The lighting device 1 shown serves to illuminate several plants 2 and includes an artificial light unit 3 for providing artificial light 3 ′ and a sunlight unit 4 for providing sunlight 4 ′, both of which serve to illuminate the plant 2 . The Be lighting device 1 also has a mixing unit 5 to He testify a mixed light 5 'from the artificial light 3' and the sunlight 4 ', and a distribution unit 6 for distributing the mixed light 5' and illuminating the plants 2 with the distributed mixed light 5'. In the present case, the distribution unit 6 also has a number of lighting units 7, through which the mixed light is distributed homogeneously. The lighting units 7 are present on top of each other, i. H. one above the other in the y-direction and each (in the y-direction) above the plants 2 to be illuminated.

The lighting device 1 also has an adjustment unit 8 for adjusting a property of the mixed light 5'. In the present case, this occurs indirectly in that the adjustment unit 8 adjusts the artificial light unit 3 and thus via the artificial light 3' (here directly adjustable) a property such as a spectral distribution and/or an intensity of the mixed light 5'. Since the lighting device 1 also has a sensor unit 9 for detecting a spectral distribution and/or an intensity of the mixed light and the adjustment unit 8 is configured, the property of the mixed light depends on the detected spectral distribution or intensity to adjust the mixed light, ie to control the artificial light unit 3 as a function of the detected spectral distribution or intensity, in the example shown a closed control circuit symbolized by the ring arrow 10 is implemented. This control circuit can also be expanded, for example, by a corresponding filter unit for optically filtering one of the lights 3', 4', 5', which means that the artificial light 3' can then be used not only to supplement the sunlight 4' , but also a dampening of certain spectral components of the sunlight 4' and thus also of the

mixed light 5'.

In the example shown, the setting unit 8 is also designed to set the properties of the mixed light in accordance with a stored regulation 11 . The stored regulation 11 is in this case adapted to the type of plants 2 and can depend on a measured variable 12, in this case soil moisture.

patent claims

1. Lighting device (1) for at least one plant (2), with

- an artificial light unit (3) for providing an artificial light (3') for illuminating the plant (2); and

- a sunlight unit (4) for providing sunlight (4') for illuminating the plant (2);

marked by

- A mixing unit (5) for generating a mixed light (5') from the artificial light (3') and the sunlight (4');

- A distribution unit (6) for distributing the mixed light (5') and illuminating the plant (2) with the distributed mixed light (5'); and

- An adjustment unit (8) for adjusting a property of the mixed light (5').

2. Lighting device (1) according to claim 1,

characterized in that

the adjustable property includes a spectral distribution and/or an intensity.

3. Lighting device (1) according to any one of the preceding claims,

characterized in that

the adjustment unit (8) is designed to adjust the property of the mixed light (5') dynamically.

4. Lighting device (1) according to any one of the preceding claims,

characterized in that

the setting unit (8) is designed to set the property of the mixed light (5') in accordance with a stored regulation (11).

5. Lighting device (1) according to claim 4,

characterized in that

the regulation (11) depends on a measured variable, in particular a time and/or a season and/or a temperature and/or an air humidity and/or a soil moisture and/or a nutrient concentration.

6. Lighting device (1) according to any one of the preceding claims,

marked by

- A sensor unit (9) for detecting a spectral distribution and/or an intensity of the sunlight (4') and/or the mixed light (5') and/or the artificial light (3');

wherein the adjustment unit (8) is designed to adjust the property of the mixed light (5') depending on the detected spectral distribution and/or the detected intensity.

7. Lighting device (1) according to any one of the preceding claims,

marked by

- A filter unit that can be set by the adjustment unit (8) for optically filtering the sunlight (4') and/or the mixed light (5') and/or the artificial light (3').

8. Lighting device (1) according to any one of the preceding claims,

characterized in that

the distribution unit (6) comprises a plurality of lighting units (7) to which the mixed light is distributed homogeneously.

9. Plant cultivation system with a lighting device (1) according to any one of the preceding claims, and with one or more of the following devices:

- A temperature control device for setting a temperature for the plant (2) that can be illuminated by the lighting device (1);

- An air humidifying device for setting an air moisture speed for the lighting device (1) illuminable Pflan ze (2);

- A soil moistening device for setting a soil moisture content for the plant (2) that can be illuminated by the lighting device (1);

- A fertilizing device for adjusting a nutrient concentration for the plant (2) which can be illuminated by the lighting device (1).

10. Method for illuminating at least one plant (2), with the method steps:

- providing an artificial light (3') for illuminating the plant (2);

- providing a sunlight (4') for illuminating the plant

(2);

- Generating a mixed light (5') from the artificial light (3') and the sunlight (4');

- setting a property of the mixed light (5'); and

- Distributing the mixed light (5') and illuminating the plant (2) with the distributed mixed light (5').