Patent Application
20250160266
The present invention relates to the field of sustainable farming systems, and more particularly to a combination of a net house and an indoor farming system.
Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
Greenhouses have been widely implemented in the past for agriculture and cultivation purposes, however showcased very high water consumption for cooling process. Data related to energy use were also observed to be high wherein greenhouses were found to consume 32 times the energy used in comparison to net houses. Also, the cooling cost in the total production cost is much higher and heavier for greenhouses resulting in increased production cost and thereby a loss of competitiveness of the local product in the market. Therefore, there is a need to improve energy and water use efficiency in the protected agriculture in hot and arid regions and to reduce the water and energy footprint as a result of agriculture in such regions.
Traditionally implemented energy generating systems for farming or cultivation arrangements have numerous drawbacks such as high costs for installation of a heating, ventilation and air conditioning (HVAC) setup, high maintenance costs, and that these systems additionally take up enormous areas or space for farming/cultivation purposes. Further disadvantages faced by traditional systems include that large acres of land or area are required for farming/cultivation, which is not always practical and feasible, increased human intervention or manual labour, which leads to plant deterioration, and expensive maintenance costs. Although systems like agrivoltaics (or agro-photovoltaics, i.e. the simultaneous use of land for both solar photovoltaic power generation and agriculture) were tried in several countries (such as Holland and Germany), this failed owing to rivalry between energy companies and farmers. Extreme weather conditions also led to the failure of this method. Further, net houses failed to support premium crops, especially during midsummer months.
Accordingly, there exists a need for a farming system, which overcomes drawbacks of traditionally employed growing techniques and/or systems.
Therefore it is an object of the present invention to develop a sustainable farming system, which overcomes drawbacks of traditionally employed growing techniques and/or systems.
There is disclosed a combined net house and indoor farming system comprising a net covering the net house while allowing sunlight to pass through; and a plurality of photovoltaic (PV); wherein the plurality of PV panels simultaneously shades the net house and supplies energy to the indoor farming system.
In another embodiment of the present invention, the plurality of PV panels cover a maximum of 50% of the net house.
In another embodiment of the present invention, the combination of the shading of the PV panels and the net enables cultivation and growth of premium crops such as lettuces and tomatoes round the year.
In another embodiment of the present invention, the net also acts as an insect net or trap.
In another embodiment of the present invention, the plurality of PV panels installed on a top portion and/or side portion of the net house.
In another embodiment of the present invention, the plurality of PV panels are directly connected to light emitting diode (LED) lights within the indoor farming system.
In another embodiment of the present invention, the LED lights are grow lights.
In another embodiment of the present invention, the proposed system further comprises sprinklers within the net house for achieving cooling during warm periods.
In an embodiment of the present invention, the plurality of PV panels are installed flat on the net house, or at inclined positions on the net house.
In an embodiment of the present invention, the plurality of PV panels are thermal cogeneration flat panels.
In an embodiment of the present invention, the plurality of PV panels comprise layers of tempered glass, a PV module, and a heat conducting sheet and pipe, in addition to an insulation layer and an alloy frame.
In an embodiment of the present invention, the plurality of PV panels possess a negative temperature effect and absorb heat energy generated on the plurality of PV panels, thereby increasing power generation capacity of the plurality of PV panels.
In an embodiment of the present invention, a portion of the generated heat energy is transported via pipes and stored in tanks to produce hot water for the indoor farming system.
In an embodiment of the present invention, the plurality of PV panels generate energy, in the form of electricity and solar heat, which are supplied to the indoor farming system.
The subject matter that is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other aspects, features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The aspects of the proposed sustainable farming system, according to the present invention will be described in conjunction with
The present invention relates to a combined net house and vertical farming system 100 as depicted in
Energy generating systems traditionally implemented have drawbacks, which generally led to high costs for installation of a heating, ventilation and air conditioning (HVAC) setup, and additionally take up enormous areas or space for farming/cultivation purposes. Drawbacks faced by traditional systems include that large acres of land or area are required for farming/cultivation, which is not always practical and feasible, increased human intervention or manual labour, which leads to plant deterioration, and expensive maintenance costs. Although systems like agrivoltaics (or agro-photovoltaics, i.e. the simultaneous use of land for both solar photovoltaic power generation and agriculture) were tried in several countries (such as Holland and Germany), this failed owing to rivalry between energy companies and farmers. Extreme weather conditions also led to the failure of this method. Further, net houses failed to support premium crops (for example lettuces, tomatoes), especially during midsummer months.
As a remedy to the drawbacks faced by previously implemented systems and methods, the present invention discloses replacing the shading net of net houses 102 with a highly transparent insect net and then covering a maximum of 50% (or half) of the roof of the net house with solar panels 104, in order to achieve 50% shading.
The installed solar panels 104 are also connected directly to a plurality of LED fixtures (with matching specifications) installed in a vertical farming system—to achieve maximum electrical efficiency. The use of net houses in agriculture has many advantages, such as, but not limited to, being a passive system with no moving parts, minimum maintenance requirements, low construction and operation costs, and minimal energy requirements. Further, a net house or a shade house acts as a barrier against strong winds, while facilitating passive ventilation without the additional need of fans, and provides sufficient protection against foreign particles and possible damages from heavy rain and/or hailstorms. A net house also facilitates in diffusing incident sunlight, eliminates scorching effects, facilitates optimum photosynthesis (photosynthesis occurs as per the formula: CO2+H2O═CH4+O2) and stops majority of insect, while trapping humidity and providing a protective cover for the plants. With an additional misting provided in warmer periods such as the summer season, up to 7-8° Celsius of cooling effect may also be achieved with net houses. Another important advantage is the shading effect provided by net houses. Preferably, 50% shading nets are recommended in regions, which receive a high concentration of solar energy throughout the year.
Thereby, it is an objective of the present invention is to enable solar energy production by installing solar panels 104 on the roofs of net houses 102, and supplying this produced energy as a source of energy for an indoor farming system 106. In accordance with the present invention, a plurality of solar panels 104 are installed either flat on the roof of the net house 102, or in an inclined or slanted position, so as to capture solar rays-irrespective of the time of the day, and irrespective of the season (summer or winter). Accordingly, direct and diffused solar rays are efficiently captured at all times. This is highly advantageous for cultivation of premium crops such as lettuces and tomatoes, round the year (which require a daily light integral or DLI value of 24-28 mol/m2/day).
Table 2 displays the energy requirements for a hybrid net house-indoor farming system.
Table 3 shows photovoltaic and thermal production capacity of a hybrid net house-indoor farming system.
Table 4 displays the production capacity and productivity for leafy greens being grown in a hybrid net house-indoor farming system.
The solar panels 104 used on the net house roofs are photovoltaic/thermal cogeneration flat panels. Each of the said panels comprise layers of tempered glass, a photovoltaic (PV) module, a heat conducting sheet and pipe, in addition to an insulation layer and an alloy frame. In an embodiment of the present invention, the PV module (possessing a negative temperature effect) 104 in accordance with the present invention absorbs the heat energy generated on the panel, and increases overall power generation capacity of the panel. Simultaneously, a portion of the generated heat energy is transported via pipes and stored in tanks to produce hot water for the indoor farming system and the plurality of PV panels generate energy, in the form of electricity and solar heat, which are supplied to the indoor farming system. Advantages of the solar panels used on the net houses include enabling approximately 88% harvesting of solar energy, 22% of solar electricity and 66% of solar heat. Further, the said panels increase PV efficiency by cooling the panel. Other perks include 25-30 years' service life, minimal maintenance requirements and being extremely inexpensive to operate.
In another embodiment, the panels 104 on the net house rooftops are shingle type connections (reliable connections), wherein the closed junctions in between the panels increase the effective area of shining light. Ribbons (flexible glue ribbons) are welded and connected from a top to a bottom portion of each of the individual cells, which are cut into individual slices (and shingled). An advantage of such a connection is flexibility and durability of the solar cell arrays (avoid cracks for a considerable duration of time). Considering the case with traditionally implemented solar panels, one of the main reasons these start losing efficiency is lack of durability, and another reason being that each individual solar cell (silicon-based) provide 0.5-0.6V each, and hence to reach a required voltage numerous such cells need to be placed back to back. The main risk encountered in such situations is shading. When a single panel is partially shaded, this leads to the entire panel being shut down owing to a diode, which was cut automatically. This is because if a panel is shaded partially, it becomes a hot spot rather than becoming cold-until it burns out. Hence, if you have a dead point, the system needs to be shortcut. Such drawbacks are eliminated through use of shingled connections.
The panels 104 are in connection with the LED grow lights needed in an indoor or vertical farming arrangement 106. PV panels 104 are moved to lay flat on the rooftops, in order to capture every bit of available solar rays, and the resulting solar energy is split to be used for powering the LEDs in buildings or constructions like the net houses, or the indoor farming systems, as well as to warm the interior of the building. In this way wastage of the available minimum amount of incident solar rays is also avoided. The only loss factor is soiling which can be optimized through daily cleaning with waterless system or dry robotic brushes. Also, the arrangement of the PV panels 104 on rooftops enables maximum protection during adverse climates, and the flexibility and ease of tilting the panels makes it easier to brush off any accumulated dust or impurities from the panels.
Methods implemented for optimizing solar photovoltaic and thermal productivity of the net house 102 rooftop include programming the PV panels 104 to be tilted or positioned at a particular angle (instead of being placed flat on the roofs) in accordance with various months of the year, as depicted in
In accordance with another aspect of the present invention and as depicted in the block diagram of
The adsorption module 204 mainly comprises a desiccant wheel/dehumidifier 205a and a heat transfer wheel 205b for heat exchange. The desiccant wheel 205a is made of a polymer-based material, and functions to output humidity from the indoor farming system 106. This module 204 also receives heat from photovoltaic and thermal panels (obtained from the sun) 104—as input, and as output dehumidifies the indoor or vertical farming system 106. In contrast to a traditional condensation process, the adsorption module 204 in accordance with the present invention allows for humidity from air to be extracted and released outside. Subsequently, dry air (dehumidified air) is the output of the adsorption module 204. Thereby no additional power/electricity is needed to further process the extracted humidity. A heat recovery wheel 205b is then used for necessary heat exchange. Air taken in by the adsorption module 204 is taken through the dehumidification sector of a rotating desiccant wheel coated with a sorption agent (hygroscopic) on which the moisture from the air deposits. An example of the sorption agent is silica. The dry air (dehumidified since the moisture is taken up by the desiccant and released outside) is then blown out into the room again. The regeneration air is then refed to a heating element in the circuit to take up new moisture.
In accordance with the present invention, no additional component is needed to provide inputs to the absorption or adsorption modules (202 and 204) of the currently proposed carbon neutral sustainable growing system 200. Both these modules require heat as input which is readily available and provided via the PV panels 104 positioned on the indoor farming building 106, or on nethouse 102 rooftops (the net houses being in direct contact with the indoor farming system). Also, outputs of each of the absorption module (chilled water), as well as the adsorption module (dehumidified air) are utilized completely in the indoor farming environment 106 and result in zero waste of resources or energy.
The proposed sustainable growth system 200 is further in combination with a desalination module 206 and an aerobic digestion module 208, to achieve a carbon neutral growth system with high yield and for producing nutrient rich fertilizer 210. Accordingly, a supply of seawater 212 is allowed towards the sustainable growth system and the farming system 200 (net houses 102 with solar panels 104, in combination with an indoor or vertical farming system 106) will not need any external energy source for its operation. The proposed system enables plants or crops being cultivated, to have access to a plurality of rich nutrients and/or minerals, and the by-product or waste product from the farming system is used as input to an aerobic digestion system 208. The desalination module 206 receives seawater 212 as input, and works to desalinate the water. As a by-product of the desalination process, a plurality of minerals and nutrients are also obtained (in addition to the extracted salt). The extracted plurality of minerals and nutrients are fed directly to the growth system, as replenishment to the plants or crops being grown. The growth system generally outputs inedible plant mass as well as mineral refuse, which in traditional systems is thrown out and wasted. However, in the present invention this inedible plant mass and mineral refuse is fed directly to an aerobic digestion module, which functions to produce organic fertilizer 210, wherein a regular input of the by-product or the waste products allows the aerobic digestion module to produce organic fertilizer every 24 hours (in contrast to the number of days taken traditionally). The produced organic fertilizer 210 is then mixed with sand (desert sand) in the right proportions, to produce nutrient rich soil. Brine (or water strongly impregnated with salt) is harvested, instead of being dumped back into the sea.
In an embodiment of the present invention, the aerobic digestion module 208 also receives food waste in addition to the inedible plant mass and mineral refuse obtained as by-products of the desalination module 206 and the sustainable growth system 200. A crusher component crushes the food waste into smaller pieces, and the crushed food waste then passes through a water-solid separator, wherein the solids move towards a composting tank, and the liquids move towards an oil separator. The oil separator then outputs waste oil (which is collected and re-used) and waste water (which is treated in a water treating system, and re-used). In the composting tank, adjustment of the temperature and required bacteria is done, and stirring processes take place adding air in between if required-resulting in fertilizer being produced (along with waste gas). Unlike traditional composting systems, the present aerobic digestion module 208 functions 24 hours a day and is very efficient in producing the organic fertilizer 210 in 24 hours (instead of 3-6 months like that in traditional systems). Further, ratios and proportions of mixing the fertilizer varies based on the plant or crop being cultivated (for example, tomatoes or lettuces). In an embodiment, desert sand is mixed along with the compost or organic fertilizer 210, to form the organic soil for plants.
In accordance with the present invention, the aerobic digestion module 208 is in connection with a crop cultivation area or farming platform, as shown in
As another aspect of the present invention, and as shown in the block diagram of
The PV panels 104 positioned on rooftops of net houses 102 assist to produce required hot water and electricity (which is a basic requirement for the HVAC system). The hot water produced is stored in large tanks such as a hot water storage tank 305. This stored hot water is circulated through the second set of pipes 303b in order to further heat external air used to dehumidify the desiccant wheel or de-humidifier wheel 205a. There are also a plurality of fans which rotate in all directions. The area in between the PV or solar panels on the rooftop and the false ceiling 302 of the indoor farming building or system is host to the ductless HVAC system 300 and acts also a heat regeneration space for the system. The false ceiling 302 has no ducting. The ductless air conditioning system is positioned within a false ceiling portion of the indoor farming arrangement, which functions as a duct for the air conditioning system. The proposed HVAC system 300 implements a desiccant wheel 205a and heat recovery wheel 205b for each shelf of the indoor farming system 106. Optimum performance is achievable when operating the proposed HVAC system in areas with hot climates, wherein heat may be recovered from the heated air coming from outside, however during nighttime when the external air is cooler, the load on the absorption chillers is reduced substantially. As shown in
Many changes, modifications, variations and other uses and applications of the subject invention will become apparent to those skilled in the art after considering this specification and the accompanying drawings, which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications, which do not depart from the spirit and scope of the invention, are deemed to be covered by the invention, which is to be limited only by the claims, which follow.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2022/051158 | 2/9/2022 | WO |
