Description:CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY
[0001] The present application is a Patent of addition that claims priority from an Indian Patent application No: 202221006247, filed on 05th February 2022.
TECHNICAL FIELD
[0002] The invention relates to a storage unit for perishable products. More specifically, the invention relates to a storage unit with enhanced evaporative cooling that does not require an external power source.
BACKGROUND
[0003] The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed subject matter.
[0004] Conventional storage units for perishable goods rely on electricity and refrigerants to extend the shelf life of perishable goods. These systems are effective and come in various shapes and sizes but consume high energy and use potentially harmful refrigerants. Further, they require a stable power supply, which is difficult to meet in developing countries where irregular power cuts for long durations are a daily routine. Generators are commonly used in such scenarios to meet power requirements, but this increases the cost of storage and capital expenses for small farmers and store owners. The farmers who cannot afford these additional costs lose out to the middleman as they do not have any alternative. This is one of the major factors affecting the global food shortage.
[0005] Alternatively, portable and power-independent cold storage solutions such as ice coolers and passive coolers are used to address this problem. However, these solutions are often limited either in their cooling capacity or operational time. Additionally, these solutions would require the replenishment of ice or other cooling agents periodically. Although these are not directly dependent on power, they increase the maintenance cost due to their dependence on ice and cooling agents.
[0006] Passive coolers, on the other hand, aim to capitalize on natural cooling processes, often involving insulation to maintain low temperatures. While they offer certain advantages in terms of energy efficiency and independence from electricity, they are not suitable for all circumstances, and their effectiveness is limited by ambient conditions.
[0007] In view of the foregoing discussion, there is a need for an improved technique to overcome the limitations of the current technologies and provide a viable, economical and portable alternative to a storage unit for perishable food products.
SUMMARY OF THE INVENTION
[0008] Accordingly, an improved technique to overcome the above problems is needed. To fulfil this need, an improved storage unit is provided. This summary is provided to introduce concepts related to a system to store and maintain items at low temperatures. More specifically, the present invention relates to a system to store and maintain items at low temperatures, without using electric energy.
[0009] Before the present system and its components are described, it must be understood that this disclosure is not limited to the particular system and its arrangement as described, as there can be multiple possible embodiments that are not expressly illustrated in the present disclosure. It is also to be understood that the terminology used in the description is for the purpose of describing the versions or embodiments only and is not intended to limit the scope of the present application. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in detecting or limiting the scope of the claimed subject matter.
[0010] In one implementation of the present disclosure, a storage unit with evaporative cooling used for storing perishable products is provided. The storage unit comprises a panel on each side. Further, the panel on at least one side includes a metal sheet layer, a cooling pad layer, an insulation balls sheet layer, a cooling pad layer, a wire mesh layer and a polypropylene sheet layer. The polypropylene sheet layer is configured to provide air permeability to the storage unit.
[0011] In an embodiment, the storage unit comprises a top panel, multiple side panels, and a bottom panel interconnected through a frame. Further, each of the multiple side panels comprises a water circulation channel, the polypropylene sheet layer, the metal sheet layer, the cooling pad layer, the insulation balls sheet layer, and the wire mesh layer.
[0012] In another embodiment, the top panel comprises a polypropylene sheet layer to provide air permeability to the storage unit, a metal sheet layer, a cooling pad layer, an insulation balls sheet layer, and a wire mesh layer.
[0013] In another embodiment, the bottom panel includes the metal sheet layer, the foam layer and the Polypropylene (PP) sheet. The metal sheet is the innermost layer, and the PP sheet is the outermost layer.
[0014] In another embodiment, the metal sheet layer is the innermost layer that is exposed to the perishable products and the polypropylene sheet layer is the outermost layer.
[0015] In another embodiment, the water circulation channel of the side panel includes an aperture to receive water and multiple drippers. The aperture and the multiple drippers are on the opposite surfaces of the water circulation channel. The water circulation channel is positioned such that water from the multiple drippers falls on the cooling pad layer. Further, the insulation balls sheet layer is positioned between two cooling pad layers.
[0016] In another embodiment, the water circulation channel of one side panel is connected to another side panel through an interconnecting pipe.
[0017] In another embodiment, the bottom panel include a drainage hole to drain the excess water from the storage unit.
[0018] In another embodiment, the relative humidity inside the storage unit is higher as compared to ambient humidity.
BRIEF DESCRIPTION OF DRAWINGS
[0019] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Elements illustrated in the figures are not necessarily drawn to scale. Embodiments of a storage unit are described, by way of example only, and with reference to the accompanying figures, in which:
[0020] Figure 1A illustrates the isometric view of an open storage unit (100) for storing perishable products, in accordance with an exemplary embodiment;
[0021] Figure 1B illustrates the isometric view of a closed storage unit (100) for storing perishable products, in accordance with an exemplary embodiment;
[0022] Figure 1C illustrates the front view of a storage unit (100) for storing perishable products, in accordance with an exemplary embodiment;
[0023] Figure 1D illustrates the side view of the storage unit (100), in accordance with an exemplary embodiment;
[0024] Figure 1E illustrates the rear view of the storage unit (100), in accordance with an exemplary embodiment;
[0025] Figure 2 illustrates a perspective view of the storage unit (100) depicting the water circulation channel (202), in accordance with an exemplary embodiment;
[0026] Figure 3 depicts the construction of the side panels (105) of the storage unit (100) and the layers included thereof, in accordance with an exemplary embodiment;
[0027] Figure 4 depicts the construction of the top panel (102) of the storage unit (100) and the layers included thereof, in accordance with an exemplary embodiment; and
[0028] Figure 5 depicts the construction of the bottom panel (104) of the storage unit (100) and the layers included thereof, in accordance with an exemplary embodiment.
DETAILED DESCRIPTION
[0029] Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0030] The terms “comprise(s)”, “comprising”, “include(s)”, “including”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, system or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or system or method. In other words, one or more elements in a system or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
[0031] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and which are shown by way of illustration-specific embodiments in which the disclosure may be practised. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
[0032] The present disclosure is related to a storage unit for perishable products. The storage unit can store and maintain the perishable products at low temperatures to improve the shelf life of the perishable products. The storage unit is based on a passive evapouration technique, and it comprises a panel on each side. The storage unit includes a top panel, multiple side panels, and a bottom panel interconnected through a frame. The panel on at least one side of the storage unit includes a polypropylene sheet layer, a metal sheet layer, a cooling pad layer, an insulation balls sheet layer, a cooling pad layer, and a wire mesh layer. The polypropylene sheet layer is configured to provide air permeability to the storage unit.
[0033] In an embodiment, the perishable products that may be stored in the storage unit (100) may include, but are not limited to, food items such as fruits, vegetables, milk products, eggs, and meat, among other perishable products. The storage unit (100) may also be used to store other non-edible perishable products such as, but not limited to, flowers, drugs, and syringes, among others.
[0034] In an embodiment, the present invention relates to a storage unit (100) for perishable products. More specifically, the invention relates to a storage unit (100) with enhanced evaporative cooling that does not require an external power source. The storage unit (100) may be provided with water once a day, therefore there is no need to provide continuous water supply to the storage unit (100). The storage unit (100) may cool the perishable products using the stored water, as a continuous water supply is not needed by the storage unit (100), the evapouration technique used for cooling is enhanced in the storage unit (100).
[0035] Figures 1A and 1B illustrate the isometric view of an open and a closed storage unit (100) for storing perishable products respectively, in accordance with an exemplary embodiment. The storage unit (100) may include a top panel (102), a bottom panel (104), and multiple side panels (105). Further, the multiple side panels (105) may include a left panel (106), a right panel (108), a front panel (110) and a rear panel (112). The system (100) may further include one or more crates (115). The crates (115) may be used to place the perishable products in the system (100). Furthermore, the storage unit (100) may be configured to hold and evapourate water in order to maintain a low temperature inside the storage unit (100).
[0036] Figures 1C, 1D and 1E illustrate the front view, side view and rear view of a storage unit (100), respectively, for storing perishable products, in accordance with an embodiment. The storage unit (100) may include a top panel (102), a bottom panel (104), and multiple side panels (105). Furthermore, the multiple side panels (105) may include a left panel (106), a right panel (108), a front panel (110) and a rear panel (112). The storage unit (100) may include the top panel (102), the bottom panel (104), and the multiple side panels (105) interconnected with a frame (114). The storage unit (100) may be configured to hold and evapourate water in order to maintain a low temperature inside the storage unit (100). In an embodiment, the panels (top panel (102), bottom panel (104), left panel (106), right panel (108), front panel (110) and rear panel (112)) may be interconnected with the frame (114) using screws, nails, and adhesives depending on the material of the panels.
[0037] In an embodiment, the frame (114) at the interconnection of the top panel (102) and the front panel (110) may include a handle (116) and a lock (118) (referring to Figure 1C). The handle (116) may be used to access the storage unit (100) through the top panel (102). Further, the lock (118) may be configured to secure the storage unit (100) by locking the top panel (102) with the front panel (110). Furthermore, the frame (114) may include a plurality of hinges (120), at the intersection of the top panel (102) and the rear panel (112) (referring to Figure 1E). The plurality of hinges (120) facilitates the movement of the top panel (102) such that the top panel (102) is opened and closed using the handle (116).
[0038] The frame (114) includes a linking means (122), at the intersection of the top panel (102) and the left panel (106) (referring to Figure 1D). The linking means (122) may be configured to connect the left panel (106) and the right panel (108) to the top panel (102). The linking means (112) may restrict the movement of the top panel (102) beyond a pre-set angle. The linking means (122) may be provided on both sides of the storage unit for improved stability.
[0039] In an embodiment, the frame (114) includes a drainage hole (124) in the bottom panel (104). For example, the drainage hole (124) may be provided at the intersection of the bottom panel (104) and the rear panel (112) (referring to Figure 1E). The drainage hole (124) may be configured to drain out excess water. The excess water that is drained out may be re-used for cooling by evapouration in the storage unit (100). Furthermore, the storage unit (100) may include one or more drainage holes (124).
[0040] Figure 2 illustrates a perspective view of the storage unit (100) depicting the water circulation channel (202), in accordance with an exemplary embodiment. The left panel (106), right panel (108), front panel (110) and rear panel (112) may include a water circulation channel (202) at the top of each panel. Further, the water circulation channel (202) of each panel is connected to the water circulation channel (202) of the other panel with interconnecting pipes (204), for facilitating water circulation between the left panel (106), right panel (108), front panel (110) and rear panel (112). Furthermore, the water circulation channel (202) may comprise multiple drippers (206). The drippers (206) may be configured to drip water on the left panel (106), right panel (108), front panel (110) and rear panel (112) to further facilitate cooling by evapouration of water.
[0041] In an embodiment of the present disclosure, panels (top panel (102), bottom panel (104), left panel (106), right panel (108), front panel (110) and rear panel (112)) of the storage unit (100) may include different layers configured to facilitate cooling by evapouration of water. The left panel (106), right panel (108), front panel (110) and rear panel (112), hereinafter referred to as side panels (105), may have similar layers.
[0042] Figure 3 depicts the construction of the side panels (105) of the storage unit (100) and the layers included thereof, in accordance with an exemplary embodiment. The side panels (105) may comprise include multiple layers configured to facilitate cooling by evapouration of water and improve relative humidity. Further, the multiple layers include a metal sheet (302), a cooling pad (304), an insulation balls sheet (306), a cooling pad (308), a wire mesh (310) and a Polypropylene (PP) sheet (312). The side panels (105) may include the metal sheet (302) as the innermost layer and the PP sheet (312) as the outermost layer.
[0043] In an embodiment of the present disclosure, side panels (105) may be enabled with a water circulation channel (202) at the top of each panel. The water circulation channel (202) may comprise multiple drippers (206). The drippers (206) may be configured to drip water on the cooling pad (304), insulation balls sheet (306) and cooling pad (308), to further facilitate cooling by evapouration of water.
[0044] Further, the water circulation channel (202) of each panel is connected to the water circulation channel (202) of the other panel with interconnecting pipes (204), for facilitating water circulation to the left panel (106), right panel (108), front panel (110) and rear panel (112).
[0045] In an embodiment, the water circulation channel (202) of the side panels (105) includes an aperture to receive water and multiple drippers (206). The aperture and the multiple drippers (206) are positioned on opposite surfaces of the water circulation channel (202). The water circulation channel (202) is positioned such that water from the multiple drippers (206) falls on the cooling pad layers (304, 308). The insulation balls sheet layer (306) is positioned between two cooling pad layers (304, 308). In an embodiment, the aperture may be covered with a plug to ensure zero leakage.
[0046] Figure 4 depicts the construction of the top panel (102) of the storage unit (100) and the layers included thereof, in accordance with an exemplary embodiment. The top panel (102) may include multiple layers configured to facilitate cooling by evapouration of water and improve relative humidity inside the storage unit (100). Further, layers may include a metal sheet (402), a cooling pad (404), an insulation balls sheet (406), a cooling pad (408), a wire mesh (410) and a Polypropylene (PP) sheet (412). The top panel (102) may include the metal sheet (402) as the innermost layer and the PP sheet (412) as the outermost layer.
[0047] Figure 5 depicts the construction of the bottom panel (104) of the storage unit (100) and the layers included thereof, in accordance with an exemplary embodiment. The bottom panel (104) may include multiple layers such as a metal sheet (502), a foam (504) and a Polypropylene (PP) sheet (506). The bottom panel (104) may include the metal sheet (502) as the innermost layer and the PP sheet (506) as the outermost layer.
[0048] In an embodiment, the foam (504) layer of the bottom panel (104) may be configured to hold water, to further facilitate cooling by evapouration of water and increase the relative humidity inside the storage unit (100).
[0049] In an embodiment, the metal sheet layers (302, 402, 502) are the innermost layers that are exposed to the perishable products, and the polypropylene sheet layers (312, 412, 506) are the outermost layers that are exposed to the external environment.
[0050] In an embodiment, the metal sheet (302, 402, 502) transfers heat from the perishable products stored in the storage unit (100) to the layers in the side panels (105) to maintain them at low temperatures. Since the temperature of the panels may be lower than the items inside the storage unit (100), the metal sheet (302, 402, 502) absorbs heat from the items inside the storage unit (100). Additionally, the metal sheet (302, 402, 502) provides a firm structure to the storage unit (100).
[0051] In an embodiment, the cooling pads (304, 308, 404, 408) cools the panels and the storage unit (100) by conduction. Further, the cooling pads (304, 308, 404, 408) may be wet due to the water falling from drippers (206), which transfers heat from the metal sheet layer (302, 402) by conduction and transfers into other layers in the side panels (105). Thus, cooling the storage unit (100) by passing fresh air, from the atmosphere, through the wet and cool surface of the cooling pads (304, 308, 404, 408) to reduce the temperature. Thus, the fresh air from the atmosphere leaving the cooling pads (304, 308, 404, 408) is humidified and cold. Furthermore, the cooling pads (304, 308, 404, 408) may be made up of materials such as but not limited to, aspen fibres, khus (Chrysopogon zizanioides) fibres, coconut fibres, palash fibres, wood shavings and synthetic fibres.
[0052] In an embodiment of the present disclosure, the insulation balls sheet (306, 406) may be configured to prevent any heat transfer from the atmosphere.
[0053] In an embodiment, the wire mesh (310, 410) of the side panels (105) and the top panel (102) respectively, provides a firm structure to the respective panels of the storage unit (100). In an embodiment, the PP sheets (312, 412, 506) may be configured to provide air permeability to the storage unit (100).
[0054] In an embodiment, the metal sheet layer (302), the metal sheet layer (402) and the metal sheet layer (502) may be identical in nature and may exhibit similar properties. Additionally, the metal sheet layers in all the panels (top panel (102), bottom panel (104), left panel (106), right panel (108), front panel (110) and rear panel (112)) may be identical.
[0055] In an embodiment, the cooling pads (304), the cooling pads (308), the cooling pads (404) and the cooling pads (408) may be identical in nature and may exhibit similar properties. Additionally, the cooling pad layers in the side panels (105) and in the top panel (102) may be identical.
[0056] In an embodiment, the insulation balls sheet layer (306) and the insulation balls sheet layer (406) may be identical in nature and may exhibit similar properties. Additionally, the insulation balls sheet layers in the side panels (105) and in the top panel (102) may be identical.
[0057] In an embodiment, the wire mesh (310) and the wire mesh (410) may be identical in nature and may exhibit similar properties. Additionally, the wire mesh layers in the side panels (105) and in the top panel (102) may be identical.
[0058] In an embodiment, the PP sheets (312), the PP sheets (412) and the PP sheets (506) may be identical in nature and may exhibit similar properties. Additionally, the PP sheet layers in all the panels (top panel (102), bottom panel (104), left panel (106), right panel (108), front panel (110) and rear panel (112)) may be identical.
[0059] In an embodiment, the order of the layers in the side panels (105) is as depicted in Fig. 3 The metal sheet layer (302) is the innermost layer that is exposed to the perishable products stored in the storage unit (100). Further, the cooling pad layer (304) is positioned between the metal sheet layer (302) and the insulation balls sheet layer (306). Further, the insulation balls sheet layer (306) is positioned between the cooling pad layer (304) and the cooling pad layer (308). Further, the cooling pad layer (308) is positioned between the insulation balls sheet layer (306) and the wire mesh layer (310). Further, the wire mesh layer (310) is positioned between the cooling pad layer (308) and the PP sheet (312). Further, the PP sheet (312) is the outermost layer that is exposed to the external environment. Additionally, the side panels (105) include the water circulation channel (202) positioned such that water from the multiple drippers (206) falls on the cooling pad layers (304, 308).
[0060] In an embodiment, the order of the layers in the top panel (102) may be depicted in Fig. 4. The metal sheet layer (402) is the innermost layer that is exposed to the perishable products stored in the storage unit (100). Further, the cooling pad layer (404) is positioned between the metal sheet layer (402) and the insulation balls sheet layer (406). Further, the insulation balls sheet layer (406) is positioned between the cooling pad layer (404) and the cooling pad layer (408). Further, the cooling pad layer (408) is positioned between the insulation balls sheet layer (406) and the wire mesh layer (410). Furthermore, the wire mesh layer (410) is positioned between the cooling pad layer (408) and the PP sheet layer (412). The PP sheet layer (412) is the outermost layer that is exposed to the external environment.
[0061] In an embodiment, the order of the layers in the bottom panel (104) is as depicted in Fig. 5. The metal sheet layer (502) is the innermost layer that is exposed to the perishable products stored in the storage unit (100). The foam layer (504) is positioned between the metal sheet layer (502) and the PP sheet layer (506). Furthermore, the PP sheet layer (506) is the outermost layer that is exposed to the external environment.
[0062] In an embodiment of the present disclosure, the storage unit (100) may be used to ripen the fruits or other similar perishable products stored inside the storage unit (100). In an embodiment, to facilitate portability the storage unit (100) may be designed to hold 15-20 litres of water for cooling by enhanced evapouration.
[0063] The storage unit (100) provides a higher relative humidity, as compared to a state-of-the-art cold storage unit operating on passive evaporation. The relative humidity is the humidity index of the cold storage unit in relation to the humidity index of the ambient atmosphere. Higher humidity is favourable to maintain the freshness of the items inside the storage unit (100). Furthermore, due to such higher relative humidity, the storage unit (100) may maintain the freshness of the products for a longer duration. The higher relative humidity may further facilitate the ripening of the items stored inside the storage unit (100).
[0064] An experiment has been conducted to compare the state-of-the-art passive evapourative storage unit with the storage unit (100) for relative humidity, and the results of the same are tabulated below. The table highlights the ambient relative humidity (RH) of the atmosphere, relative humidity (RH) of the state-of-the-art passive evapourative cold storage unit and relative humidity (RH) of the storage unit (100).
Ambient State-of-the-art cold storage unit Storage unit (100)
Date/time RH Date/time RH Date/time RH
7/20/2023
7:08:24 PM 85.90 7/20/2023
7:03:40 PM 88.90 7/20/2023
7:03:47 PM 90.60
7/20/2023
7:13:24 PM 86.10 7/20/2023
7:08:40 PM 86.40 7/20/2023
7:08:47 PM 89.30
7/20/2023
7:18:24 PM 86.50 7/20/2023
7:13:40 PM 86.60 7/20/2023
7:13:47 PM 89.50
7/20/2023
7:23:24 PM 86.60 7/20/2023
7:18:40 PM 87.00 7/20/2023
7:18:47 PM 89.80
7/20/2023
7:28:24 PM 86.70 7/20/2023
7:23:40 PM 87.10 7/20/2023
7:23:47 PM 89.80
7/20/2023
7:33:24 PM 87.10 7/20/2023
7:28:40 PM 87.30 7/20/2023
7:28:47 PM 90.00
7/20/2023
7:38:24 PM 87.30 7/20/2023
7:33:40 PM 87.60 7/20/2023
7:33:47 PM 90.20
7/20/2023
7:43:24 PM 87.50 7/20/2023
7:38:40 PM 87.80 7/20/2023
7:38:47 PM 90.40
7/20/2023
7:48:24 PM 87.70 7/20/2023
7:43:40 PM 88.00 7/20/2023
7:43:47 PM 90.60
7/20/2023
7:53:24 PM 87.80 7/20/2023
7:48:40 PM 88.10 7/20/2023
7:48:47 PM 90.80
7/20/2023
7:53:24 PM 87.80 7/20/2023
7:53:40 PM 88.20 7/20/2023
7:53:47 PM 90.80
[0065] The storage unit (100) disclosed herein overcomes the limitations of the prior arts and is advantageous in improving the shelf life of the perishable products by improving the relative humidity. Additionally, the storage unit (100) has the following advantages:
– Energy Efficiency: The disclosed cooling method is highly energy-efficient since it does not rely on electricity, making it ideal for regions with intermittent or no access to power.
– Cost-Effective: The storage unit (100) components are relatively simple and cost-effective to manufacture and maintain, making it accessible to a wide range of users.
– Environmental Benefits: By using water evaporation, the present invention reduces the reliance on refrigerants and electricity, contributing to an eco-friendly approach to cold storage.
– Versatile Applications: The present invention can be applied not only in traditional cold storage units but also in transportation storage units like refrigerated trucks and containers.
, Claims:We Claim:
1. A storage unit (100) with enhanced evaporative cooling used for storing perishable products, the storage unit (100) comprises a panel on each side of the storage unit (100), characterized in that the panel on at least one side includes a polypropylene sheet layer (312) to provide air permeability to the storage unit, a metal sheet layer (302), a cooling pad layer (304, 308), an insulation balls sheet layer (306), and a wire mesh layer (310).
2. The storage unit (100) as claimed in claim 1, wherein the storage unit (100) further comprises a top panel (102), multiple side panels (105), and a bottom panel (104) interconnected through a frame (114); wherein each of the multiple side panels (105) comprises a water circulation channel (202), the polypropylene sheet layer (312), the metal sheet layer (302), the cooling pad layers (304, 308), the insulation balls sheet layer (306), and the wire mesh layer (310).
3. The storage unit (100) as claimed in claim 2, wherein the top panel (102) comprises a polypropylene sheet layer (412) to provide air permeability to the storage unit, a metal sheet layer (402), a cooling pad layer (404), an insulation balls sheet layer (406), and a wire mesh layer (410)
4. The storage unit (100) as claimed in claim 2, wherein the bottom panel (104) comprises the metal sheet layer (502), the foam layer (504) and the Polypropylene (PP) sheet (506); and wherein the metal sheet (502) as the innermost layer and the PP sheet (506) as the outermost layer.
5. The storage unit (100) as claimed in claim 2, wherein the metal sheet layer (302, 402, 502) is the innermost layer that is exposed to the perishable products, and the polypropylene sheet layer (312, 412, 506) is the outermost layer.
6. The storage unit (100) as claimed in claim 2, wherein the water circulation channel (202) of the side panels (105) includes an aperture to receive water and multiple drippers (206), wherein the aperture and the multiple drippers (206) on the opposite surfaces of the water circulation channel (202); wherein the water circulation channel (202) is positioned such that water from the multiple drippers (206) falls on the cooling pad layer (304, 308); and wherein the insulation balls sheet layer (306) is positioned between two cooling pad layers (304, 308).
7. The storage unit (100) as claimed in claim 6, wherein the water circulation channel (202) of one side panel is connected to another side panel through an interconnecting pipe (204).
8. The storage unit (100) as claimed in claim 2, wherein the bottom panel (104) include a drainage hole (124) to drain the excess water from the storage unit (100).
9. The storage unit (100) as claimed in claim 1, wherein the relative humidity inside the storage unit (100) is higher as compared to ambient humidity.